No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
The effect of savoury plants, fermented with lactic acid bacteria, on the microbiological contamination, quality, and acceptability of unripened curd cheese
... The presence of L. acidophilus in cheese caused a lower pH and acidity compared to the control sample after 30 days of storage. Similar results were obtained by Mozuriene et al. (2016). The lower presence of mesophilic aerobic bacteria due to the inhibitory action of L. acidophilus may trigger a lower production of acidic metabolites and thus a lower acidity. ...
... Table 1). Santacruz and Castro (2018) showed that viability of L. acidophilus decreased along storage, however the viable cells inhibited the development of mesophilic aerobic (Mozuriene et al., 2016) and Salmonella. Coatings were able to control the release of the antimicrobial agents on the cheese surface improving the microbiological quality of the cheese (Santacruz and Castro, 2018;Krishnan et al., 2015) and Salmonella spp. in fresh cheese. ...
... Both received a rating between "I neither like nor dislike" and "I like it moderately", with values of 3.63 and 3.50 for coated and control sample, respectively. Previous works showed similar results; in fact, LAB strains increased the acceptability and shelf-life of unripe curd cheese (Mozuriene et al., 2016). Coelho et al. (2014) found no significant differences in overall sensory evaluation of fresh cheese. ...
The fresh cheese produced in the province of Manabí is an Ecuadorian artisan cheese. The processing conditions commonly do not comply Ecuadorian regulations, resulting in the presence of pathogenic microorganisms such as Salmonella. The high number of cases of Salmonellosis in the province of Manabí justifies the need to identify and control the possible sources of this pathogenic microorganism. In the present work, the effect of the addition of Lactobacillus acidophilus to fresh cheese was studied, by immersing it in a starch solution with 1x108 CFU mL-1 of L. acidophilus with further storage for 30 days at 4 °C. The pH, acidity, weight loss, instrumental firmness, number of CFU of mesophilic aerobic bacteria and acceptability of fresh cheese were analyzed. At the same time, a duo-trio analysis was carried out, followed by a satisfaction analysis with the participation of semi-trained panelists. The presence of L. acidophilus reduced the pH and acidity in the fresh cheese in relation to the control sample. Satisfaction results, on a five-point hedonic scale, which ranged from 1 (I dislike it very much) to 5 (I like it very much), showed that the cheese treated with L. acidophilus and the control sample received a rating between “I neither like nor dislike” and “I like it moderately”, with values of 3.63 for the treated sample and 3.50 for the control. The application of L. acidophilus did not affect the organoleptic acceptability of cheese and produced less changes in pH, acidity and weight loss during storage for 30 days at 4 °C in relation to the control sample.
... Lactic acid bacteria are the dominant indigenous microorganisms of raw milk cheese, producing pathogen-inhibiting substances and leading to the manufacture of cheese with desirable microbiological qualities (Tamang et al., 2016). Our previous research confirmed that the positive effect of LAB on raw milk fresh cheese can be enhanced by combining LAB and savory plant bioproducts (Mozuriene et al., 2016). Plant bioproducts significantly reduced the counts of enterobacteria, yeast, fungi, and spores of mesophilic bacteria in cheese samples and increased the amount of volatile compounds in cheese. ...
... Plant bioproducts significantly reduced the counts of enterobacteria, yeast, fungi, and spores of mesophilic bacteria in cheese samples and increased the amount of volatile compounds in cheese. Bioproducts derived from a combination of LAB and savory plants increased the acceptability and shelf life of cow milk curd cheese, and therefore can be recommended for the production of better quality curd cheese (Mozuriene et al., 2016). ...
Goat milk cheeses have become popular recently; however, many consumers do not choose these products because they have specific sensory properties that are not acceptable to all consumers and the shelf life of the cheese is short. The concept of this work was to increase overall acceptability and shelf life of unripened goat milk cheese by using Ocimum basilicum and lactic acid bacteria (Lactobacillus plantarum LUHS135, Lactobacillus paracasei LUHS244, Pediococcus pentosaceus LUHS100, Pediococcus acidilactici LUHS29, and Lactobacillus brevis LUHS140) bioproducts (basil-LAB) immobilized in agar. A basil-LAB bioproduct could be a promising multifunctional ingredient for cheese manufacturing because it has a low pH, high LAB count, and high total phenolic compound content (after fermentation pH decreased by 25.4%, LAB count averaged 7.2 log10 cfu/g, and total phenolic compound content increased by 30.9%). Use of different LAB in the preparation of basil-LAB bioproducts had a significant influence on cheese pH and hardness, and compared with cheese samples prepared with nonfermented basil, cheese samples prepared with basil-LAB bioproducts had, on average, higher pH (by 2.6%) and lower hardness (by 36.0%), similar to the control cheese (without basil). Overall acceptability of cheese was significantly influenced by the basil-LAB bioproduct immobilization process; in all cases, cheese samples prepared with fermented and immobilized basil-LAB bioproduct had better acceptability (5 points). After 120 h of storage, cheese samples prepared with basil-LAB bioproducts fermented with LUHS135, LUHS244 and LUHS140, no enterobacteria were found, and we detected strong negative and moderate negative correlations, respectively, of LAB count with enterobacteria count and yeast/mold count (r = -0.7939 and r = -0.4495, respectively). Finally, immobilization increased LAB viability in fresh goat milk cheese, which led to a reduction in enterobacteria and mold/yeast contamination during storage and an increase in overall acceptability compared with nonimmobilized basil-LAB. Therefore, basil-LAB bioproducts fermented with LUHS135, LUHS244, and LUHS140 strains can be recommended for preparing fresh goat milk cheese with extended shelf life and high acceptability.
... Jia et al. (2020) reported that relatively high concentrations of estragole and trans-anethole in cassia and fennel extracts contributed most to their inhibitory effects on BA formation. The effectiveness of garlic has been attributed to the presence of allicin (Mah, Kim, and Hwang 2009;Zhou et al. 2016), whereas thyme, Thymbra spicata, and Satureja montana EOs have antimicrobial properties through phenolic compounds such as carvacrol and thymol (Bozkurt 2006;Mozuriene et al. 2016;Yu et al. 2021). Owing to their high hydrophobicity, the antimicrobial effect of EOs and their components (for example, thymol and carvacrol) is attributed to the disturbance of the bacterial cell membrane lipid fraction. ...
Fermented food has unique properties and high nutritional value, and thus, should constitute a basic element of a balanced and health-promoting diet. However, it can accumulate considerable amount of biogenic amines (BAs), which ingested in excess can lead to adverse health effects. The application of plant-derived additives represents a promising strategy to ensure safety or enhance the functional and organoleptic properties of fermented food. This review summarizes currently available data on the application of plant-origin additives with the aim to reduce BA content in fermented products. The importance of ensuring fermented food safety has been highlighted considering the growing evidence of beneficial effects resulting from the consumption of this type of food, as well as the increasing number of individuals sensitive to BAs. The examined plant-origin additives reduced the BA concentration to varying degrees, and their efficacy depended on the type of additive, matrix, autochthonous, and inoculated microorganisms, as well as the manufacturing conditions. The main mechanisms of action include antimicrobial effects and the inhibition of microbial decarboxylases. Further research on the optimization of bioactive substances extraction, standardization of their chemical composition, and development of detailed procedures for its use in fermented products manufacturing are needed.
... A short shelf life is also considered the greatest problem of unripened curd cheeses prepared from cow milk. Mozuriene et al. reported the effect of savoury plants fermented with sourdough LAB on the quality parameters of unripened curd cheese [75]. For the preparation of unripened curd cheese, bacteriocin-producing sourdough LAB strains were selected. ...
This review intends to highlight the fact that bread sourdough is a very promising source of technological, antimicrobial, toxin-degrading, immune system-, and faecal microbiota-modelling biological agents for the preparation of food, nutraceuticals, and feed, which has great potential at industrial biotechnology scale. There are many applications of sourdough lactic acid bacteria (LAB), which are the main microorganisms in spontaneous sourdough. In addition to their application as pure technological strains in the food and feed industries, taking into consideration the specific properties of these microorganisms (antimicrobial, antifungal, immuno-, and microbiota-modulating, etc.), they are used as valuable ingredients in higher-value food as well as nutraceutical formulations. Additionally, a very promising application of LAB is their use in combination with plant- and/or animal-based ingredients to increase the functional properties of the whole combination due to different mechanisms of action, as well as desirable symbiotic activity. In addition to traditional foods prepared using sourdough microorganisms (bread, biscuits, meat products, dairy, beverages, etc.), they could find application in the preparation of added-value ingredients for the food, nutraceutical, and feed industries. Finally, this mini-review gives a brief introduction to the possible applications of sourdough LAB in the food, feed, and nutraceutical industries.
... In Asia it is widely cultivated as a culinary herb. Due to the attractive aroma, savory herbs, both dried and fermented, are used as flavoring substances and natural preservatives in food processing [7]. This plant is used as a traditional medicinal herb in Europe, and the medicinal plant raw material of savory is the aerial part of the plant-Herba Satureae [8,9]. ...
Satureja hortensis L. is an annual herbaceous plant of the Lamiaceae Lindl. family. S. hortensis L., related to thyme and rosemary, is used as spice and traditional medicinal herb in Europe. Mainly due to the polyphenols contained in S. hortensis L., this plant exhibits multiple biological effects. However, therapeutic effects on cells, including skin tumors, have not yet been studied. Therefore, the aim of this study was to compare the composition and the resulting antioxidant as well as biological properties [on melanocytes and melanoma cells] of summer, savory growing in botanical garden of Vytautas Magnus University in middle Lithuania climatic conditions, collected during various phases of vegetation. It has been shown that the budding phase alcohol extract of this plant contains the largest amounts of polyphenols, including rutin and rosemary acid, which promote the radical scavenging activity and antioxidant properties. In contrast, the extract from the massive flowering phase already at a concentration of 12.5 µg/mL reduces the survival of melanoma cells to 60% with 90% melanocytes survival. In addition, extracts from beginning of flowering and end of flowering at a concentration of 25 µg/mL, containing significantly less rutin and rosmarinic acid, in combination with irradiation of cells with UVB, significantly increased the lipid peroxidation process, particularly in melanoma cells. These data indicate the possibility of using extracts from S. hortensis L. to modulate/differentiate the metabolism of normal and tumor skin cells.
... However, the studies revealed the microbiota metabolism of D(−) and L(+) lactic acid in fermented products are scarce. Data on the ratio of lactic acid isomers was published for sauerkraut and cheese [53,54]. Different LAB showed different production ratios of D and L lactic acid [52,55]. ...
This study aims to develop nutraceutical beverages containing food processing by-products in their formulation, and determine the opinion of consumers. This is done by testing whether they know that the main ingredients of the product are by-products, performing an overall acceptability test of the developed beverages, and evaluating the emotions induced by the newly developed beverages for consumers. The main ingredients used for the preparation of added-value beverages were fermented milk permeate (containing galactooligosaccharides), extruded and fermented wheat bran (WB) (containing ≥6.0 log10 CFU g−1 viable antimicrobial properties showing lactic acid bacteria (LAB) strains), and different fruit/berry by-products (FBB) (as a source of compounds showing antioxidant properties). The definition of the quantities of bioactive ingredients was based on the overall acceptability of the prepared beverages, as well as on emotions induced in consumers by the tested beverages. Functional properties of the developed beverages were proofed by the evaluation of their antimicrobial and antioxidant properties, as well as viable LAB count during storage. Desirable changes in extruded and fermented WB were obtained: Fermentation reduced sugar concentration and pH in samples with predominant lactic acid isomer L(+). In addition, the viable LAB count in the substrate was higher than 6.0 log10 CFU g−1, and no enterobacteria remained. By comparing the overall acceptability of the beverages enriched with WB, the highest overall acceptability was shown for the samples prepared with 10 g of the extruded and fermented WB (7.9 points). FBB showed desirable antimicrobial activity: Shepherd inhibited—2, sea buckthorn—3, blueberries—5, and raspberries—7 pathogens from the 10 tested. Comparing different beverage groups prepared with different types of FBB, in most cases (except sea buckthorn), by increasing FBB content the beverages overall acceptability was increased, and the highest score (on average, 9.5 points) was obtained for the samples prepared with 5.0 and 7.5 g of blueberries FBB. Moreover, a very strong positive correlation (r = 0.8525) was found between overall acceptability and emotion “happy” induced in consumers by the prepared beverages enriched with extruded and fermented WB and FBB. By comparing the samples prepared with the addition of WB with samples prepared with WB and FBB, it was observed that most FBB increased total phenolic compounds (TPC) content (on average, by 9.0%), except in the case of samples prepared with sea buckthorn. A very high positive correlation (r = 0.9919) was established between TPC and antioxidant activity. Finally, it can be stated that the newly developed nutraceutical beverages were acceptable for consumers, induced positive emotions, and possessed desirable antimicrobial and antioxidant properties, while being prepared in a sustainable and environmentally friendly manner.
... Upper Mozuriene et al. 2016;, 2017; however, these studies fail to characterize the role of FACS, specifically AUs, as it pertains to consumer behavior and stimuli evaluation. Additional approaches exist, such as those from the field of neuromarketing, to understand how internal and external forces (e.g. an individual's internal emotional experience versus emotional expression by entities outside of the individual) might shift consumers from one pattern of decisions to another (Breiter et al. 2015). ...
Sensory and consumer sciences seek to comprehend the influences of sensory perception on consumer behaviors such as product liking and purchase. The food industry assesses product liking through hedonic testing but often does not capture affectual response as it pertains to product-generated (PG) and product-associated (PA) emotions. This research sought to assess the application of PA and PG emotion methodology to better understand consumer experiences. A systematic review of the existing literature was performed that focused on the Facial Action Coding System (FACS) and its use to investigate consumer affect and characterize human emotional response to product-based stimuli, which revealed inconsistencies in how FACS is carried out as well as how emotional response is inferred from Action Unit (AU) activation. Automatic Facial Expression Analysis (AFEA), which automates FACS and translates the facial muscular positioning into the basic universal emotions, was then used in a two-part study. In the first study (n=50 participants), AFEA, a Check-All-That-Apply (CATA) emotions questionnaire, and a Single-Target Implicit Association Test (ST-IAT) were used to characterize the relationship between PA as well as PG emotions and consumer behavior (acceptability, purchase intent) towards milk in various types of packaging (k=6). The ST-IAT did not yield significant PA emotions for packaged milk (p>0.05), but correspondence analysis of CATA data produced PA emotion insights including term selection based on arousal and underlying approach/withdrawal motivation related to packaging pigmentation. Time series statistical analysis of AFEA data provided increased insights on significant emotion expression, but the lack of difference (p>0.05) between certain expressed emotions that maintain no related AUs, such as happy and disgust, indicates that AFEA software may not be identifying AUs and determining emotion-based inferences in agreement with FACS. In the second study, AFEA data from the sensory evaluation (n=48 participants) of light-exposed milk stimuli (k=4) stored in packaging with various light-blocking properties) underwent time series statistical analysis to determine if the sensory-engaging nature of control stimuli could impact time series statistical analysis of AFEA data. When compared against the limited sensory engaging (blank screen) control, contempt, happy, and angry were expressed more intensely (p<0.025) and with greater incidence for the light-exposed milk stimuli; neutral was expressed exclusively in the same manner for the blank screen. Comparatively, intense neutral expression (p<0.025) was brief, fragmented, and often accompanied by intense (albeit fleeting) expressions of happy, sad, or contempt for the sensory engaging control (water); emotions such as surprised, scared, and sad were expressed similarly for the light-exposed milk stimuli. As such, it was determined that care should be taken while comparing the control and experimental stimuli in time series analysis as facial activation of muscles/AUs related to sensory perception (e.g., chewing, smelling) can impact the resulting interpretation. Collectively, the use of PA and PG emotion methodology provided additional insights on consumer-product related behaviors. However, it is hard to conclude whether AFEA is yielding emotional interpretations based on true facial expression of emotion or facial actions related to sensory perception for consumer products such as foods and beverages.
... More recently, Noldus FaceReader TM (version 6.0) has proven to be a reliable indicator of facial expressions of basic emotions, although it could stand to become more robust with respect to FACS coding (Lewinski et al., 2014d). AFEA technology has been used in a variety of consumeraffective research and marketing studies (de Wijk et al., 2012He et al., 2012aHe et al., ,b, 2014He et al., , 2016He et al., , 2017Garcia-Burgos and Zamora, 2013;Lewinski et al., 2014a,b,c;Chavaglia and Filipe, 2015;Crist et al., 2016;Mozuriene et al., 2016;Walsh et al., 2017a,b); however, these studies fail to characterize the role of FACS, specifically AUs, as it pertains to consumer emotional behavior and stimuli evaluation. Additional approaches exist, such as those from the field of neuromarketing, to understand how internal and external forces (e.g., an individual's internal emotional experience vs. emotional expression by entities outside of the individual) might shift consumers from one pattern of decisions to another (Breiter et al., 2015). ...
To characterize human emotions, researchers have increasingly utilized Automatic Facial Expression Analysis (AFEA), which automates the Facial Action Coding System (FACS) and translates the facial muscular positioning into the basic universal emotions. There is broad interest in the application of FACS for assessing consumer expressions as an indication of emotions to consumer product-stimuli. However, the translation of FACS to characterization of emotions is elusive in the literature. The aim of this systematic review is to give an overview of how FACS has been used to investigate human emotional behavior to consumer product-based stimuli. The search was limited to studies published in English after 1978, conducted on humans, using FACS or its action units to investigate affect, where emotional response is elicited by consumer product-based stimuli evoking at least one of the five senses. The search resulted in an initial total of 1,935 records, of which 55 studies were extracted and categorized based on the outcomes of interest including (i) method of FACS implementation; (ii) purpose of study; (iii) consumer product-based stimuli used; and (iv) measures of affect validation. Most studies implemented FACS manually (73%) to develop products and/or software (20%) and used consumer product-based stimuli that had known and/or defined capacity to evoke a particular affective response, such as films and/or movie clips (20%); minimal attention was paid to consumer products with low levels of emotional competence or with unknown affective impact. The vast majority of studies (53%) did not validate FACS-determined affect and, of the validation measures that were used, most tended to be discontinuous in nature and only captured affect as it holistically related to an experience. This review illuminated some inconsistencies in how FACS is carried out as well as how emotional response is inferred from facial muscle activation. This may prompt researchers to consider measuring the total consumer experience by employing a variety of methodologies in addition to FACS and its emotion-based interpretation guide. Such strategies may better conceptualize consumers' experience with products of low, unknown, and/or undefined capacity to evoke an affective response such as product prototypes, line extensions, etc.
... In human beings these peptides or proteins play a very significant role in innate immunity system where they protect against various predominant microorganisms i.e. bacteria, fungi, yeast and viruses (Reddy et al., 2004). The antimicrobial peptides produced by bacteria are referred as bacteriocins, which serves as a reservoir of natural biopreservatives with various food applications as they increase the shelf-life and nutritional value of many food product like cheese, bread, meat and meat products etc. (Juodeikiene et al., 2013;Bartkiene et al., 2014;Stimbirys et al., 2015;Mozuriene et al., 2016). Bacteriocins are ribosomally synthesized extracellularly released bioactive antimicrobial peptides that inhibit closely related bacterial species through various mechanisms i.e. permeabilizing the target cell membrane, inhibiting the cell wall synthesis or through inhibiting the RNAse or DNAse activity (Cotter et al., 2005). ...
The demand of bacteriocins has been increased due to their strong antimicrobial activity against various food spoiling and food-borne pathogens. The present research work has focused upon the isolation, identification and rapid screening of potent bacteriocin producing microorganism from different fruits, vegetables and animal samples. Collected samples were screened for bacteriocin producing strains. Isolates were analyzed for its antimicrobial potential and identified by biochemical characterization. The most potent isolate was then subjected to rapid identification of bacteriocin by LCMS analysis.The strain isolated from Mango, chick intestine and rectum of goat were selected as the potent bacteriocin producing isolates. Among them the strain isolated from the source of mango showed highest zone of inhibition against both gram positive and gram negative food spoilage pathogens, i.e. Shigella, Salmonella and Listeria. The strain was identifiedas Bacillus sp.through biochemical characterization. Crude extract of production medium inoculated with Bacillus sp. was then subjected to LC-MS analysis for rapid identificationof bacteriocin where it showed the presence of partial sequence of GPGTSAVGTGHVQK which was found to be overlapping with Linocin M18.LCMS was used as a rapid identification tool for the presence of bacteriocins. The bacteriocin produced by Bacillus sp. can be exploited by various food industries considering its worthy characteristics.
... The formation of volatile compounds in tested cheese samples also varied between used bacteria for cheese manufacturing. The aroma of cheese mainly depends on the lactic acid bacteria, used in fermentation process [49]; however, some compounds, for example, 2,6-dimethyl-4-heptanol, could be related to raw milk, as after pasteurization, this compound was not detected. ...
The main task of the present study was to evaluate an impact of three nisin Z-producing Lactococcus lactis bacteria newly isolated from raw goat milk for some fresh cow cheese characteristics during the storage. Microbiological evaluation for Listeria monocytogenes, Staphylococcus aureus, and viable lactic acid bacteria counts and determination of pH, titratable acidity, and lactic acid concentration of produced cheese were performed after 0, 24, 48, 72, and 96 h. Sensory analysis for the evaluation of acidity, flavor intensity, color intensity, bitterness, and crumbliness of prepared cheese was performed. The changes of volatile compounds in fresh cheese were evaluated using headspace solid phase microextraction (SPME) coupled with gas chromatography-mass spectrometry. Chemometric methods were applied for the data analysis. Study showed that tested bacteria are suitable for the manufacturing of fresh cheese and possible application for fresh cheese biopreservation, as pathogenic bacteria did not grow during 4 days (96 h); chemometric analysis revealed that L. lactis strain LL56 was the most similar to commercially available L. lactis ATCC11454.
... L(+)-Lactic acid is used in the food industry in many ways because the human body can only assimilate this form of lactic acid. 6 On the contrary, Lactobacillus bulgaricus, commonly used in the dairy industry to produce yogurt, converts 90% of the pyruvate into D-lactic acid and triggers the aggregation of casein micelles. 7 The generation of lactic acid from pyruvate by lactate dehydrogenase (LDH) is a main step LAB use to regenerate NAD + ; therefore, all LAB harbor a large amount of NAD + -dependent LDH. 8 In the genome of LAB, stereospecific L-or D-LDHs are encoded that are responsible for producing the corresponding lactic acids. ...
... The recent studies showed bacteriocins producing LAB that could increase phenolic compounds, antioxidant activity and/or volatile compounds are obtained during the fermentation of medicinal plants ( Bartkiene et al. 2014aBartkiene et al. , 2015. The further usage of such fermented plant bioproducts in the production of meat products, bread and cheese allows to increase acceptability, shelflife or even nutritional value of the food products (Juodeikiene et al. 2013; Bartkiene et al. 2014a; Stimbirys et al. 2015; Mozuriene et al. 2016. The fermentation of milk with grain extrudates fermented with bacteriocin producing Lactobacillus sakei KTU056 and Pediococcus pentosaceus KTU058 bacteria allowed to reduce the amount of coliform bacteria if the final product is made from the raw milk (Bartkienė et al. 2014b ). ...
The scientific interest for the search of natural means of microbial inhibitors has not faded for several years. A search of natural antibiotics, so-called bacteriocins which are produced by lactic acid bacteria (LAB), gains a huge attention of the scientists in the last century, in order to reduce the usage of synthetic food additives. Pure bacteriocins with wide spectra of antibacterial activity are promising among the natural biopreservatives. The usage of bacteriocin(s) producing LAB as starter culture for the fermentation of some food products, in order to increase their shelf-life, when synthetic preservatives are not allowable, is also possible. There are a lot of studies focusing on the isolation of new bacteriocins from traditional fermented food, dairy products and other foods or sometimes even from unusual non-food matrices. Bacteriocins producing bacteria have been isolated from different sources with the different antibacterial activity against food-borne microorganisms. This review covers the classification of bacteriocins, diversity of sources of bacteriocin(s) producing LAB, antibacterial spectra of isolated bacteriocins and analytical methods for the bacteriocin purification and analysis within the last 15 years.
... The recordings with a resolution of 640 Â 480 at 25 frames per second were saved as AVI files and analysed with FaceReader 5 Software (Noldus Information Technology, Wageningen, The Netherlands). FaceReader is the complete facial expression analysis software used for food product analysis (Danner, Sidorkina, Joechl, & Duerrschmid, 2014;He, Boesveldt, de Graaf, & de Wijk, 2016;Mozuriene et al., 2016). It automatically analyses 6 basic facial expressions (happy, sad, angry, disgusted, scared, and surprized) in a panellist face, expressing the intensity of emotion in a scale from 0 to 1. ...
Rye sourdough bread has a special place in the culture of Baltic states and is still very popular. The whole process of rye bread preparation encompasses rye sourdough fermentation, dough mixing, proofing, molding, and baking. Depending on the recipe and the region rye flour scalding process can be also included. The present chapter gives an overview of historical aspects of rye sourdough bread making in Estonia, Latvia and Lithuania and describes different technological schemes of rye bread making. Diversity and properties of dominant lactic acid bacteria isolated from industrial and spontaneous rye sourdoughs are given. Their novel applications in non-cereal products are also presented.
Several studies have assessed the therapeutic potential of natural products against mastitis, but only a few have evaluated the impacts of this alternative therapy on the main properties of milk and dairy products. In this study, we observed how the treatment of mastitis with ethanolic extract of Jatobá (Hymenaea martiana Hayne) influenced the physicochemical and sensory characteristics of coalho cheese. An ointment containing the ethanolic extract was prepared for intramammary use in six dairy goats. The experiment was conducted in three experimental moments. Milking was performed, manually, and both milk and cheese were subjected to physicochemical and sensory tests. No difference was observed (p>0.05) in the physicochemical aspects of milk between the studied groups. The solids-non-fat showed a statistical difference between experimental moments M1 and M2. The protein means varied from 3.33 to 3.62, and there was a statistical difference between the two moments, while the lactose means varied from 4.79 to 5.38%. The physicochemical aspects of cheese remained similar with both treatments. Except for appearance, the sensory characteristics showed no statistical difference. In conclusion, the use of Jatobá extract ointment did not influence the physicochemical and sensory characteristics of goat milk or cheese.
Keywords:
mastitis; phytotherapy; dairy goat farming; technology; coalho cheese
Symphony orchestra of multi-microorganisms characterizes the solid-state acetic acid fermentation process of Chinese cereal vinegars. Lactate is the predominant non-volatile acid and plays indispensable roles in flavor formation. This study investigated the microbial consortia driving the metabolism of D-/l-lactate during fermentation. Sequencing analysis based on D-/l-lactate dehydrogenase genes demonstrated that Lactobacillus (relative abundance: > 95%) dominated the production of both d-lactate and l-lactate, showing species-specific features between the two types. Lactobacillus helveticus (>65%) and L. reuteri (∼80%) respectively dominated L- and d-lactate-producing communities. D-/l-lactate production and utilization capabilities of eight predominant Lactobacillus strains were determined by culture-dependent approach. Subsequently, D-/l-lactate producer L. plantarum M10-1 (D:L ≈ 1:1), l-lactate producer L. casei 21M3-1 (D:L ≈ 0.2:9.8) and D-/l-lactate utilizer Acetobacter pasteurianus G3-2 were selected to modulate the metabolic flux of D-/l-lactate of microbial consortia. The production ratio of D-/l-lactate was correspondingly shifted coupling with microbial consortia changes. Bioaugmentation with L. casei 21M3-1 merely enhanced l-lactate production, displaying ∼4-fold elevation at the end of fermentation. Addition of L. plantarum M10-1 twice increased both D- and l-lactate production, while A. pasteurianus G3-2 decreased the content of D-/l-isomer. Our results provided an alternative strategy to specifically manipulate the metabolic flux within microbial consortia of certain ecological niches.
Lactic acid production by Rhizopus oryzae NRRL 395 immobilized in polyurethane foam was investigated by using response surface methodology. A 2 3 full-factorial central composite design was chosen to explain three independent variables; glucose concentration, pH and agitation rate. The model F-value (17.01) shows that predicted model is suitable for good fitting. Linear and quadratic effects of glucose concentration and quadratic effect of agitation rate were shown to be significant for lactic acid production. Maximum lactic acid production 93.2 g/l was obtained using a glucose concentration of 150 g/l, pH 6.39 and agitation rate 147 rpm. Glucose concentration and agitation rate were found as limiting parameters. So, little variation of these parameters alters production of lactic acid. Initial pH has no effect on lactic acid production due to neutralizing agent. Production of lactic acid from immobilized whole cells which are under optimum conditions was determined about 55% that is higher than production of lactic acid from suspension culture systems. Keywords: Lactic acid, Rhizopus oryzae , immobilization, response surface methodology African Journal of Biotechnology Vol. 11(34), pp. 8546-8552, 26 April, 2012
Pediococcus acidilactici LAB 5 produces antifungal compound(s), as well as bacteriocin, which was isolated from vacuum packed fermented meat. This bacterium exhibits varying degrees of antifungal activity against a number of food and feed home molds and plant pathogenic fungi, such as Alternaria solani, Aspergillus fumigaus, A. parasiticus, Cladosporium herbarum, Colletotrichum acutatum, Curvularia lunata, Fusarium oxysporum, Microsporium sp, Mucor sp, and Penicillium sp. The production of antifungal compound(s) showed a great degree of media specificity and it was strictly restricted to MRS agar media. No production of antifungal compounds was detected in TGE, and TGE(+) Tween 80 plates, though the latter supported the highest amount of bacteriocin production at 37 degrees C after 24 hrs. Antifungal compound produced by LAB 5 was extracted using diethyl ether. The minimum inhibitory concentration (MlC) and minimum fungicidal concentration (MFC) of the compound were determined against Curvularia lunata. Chemically the antifungal substance was a phenolic compound with aromatic unsaturation, as evidenced by UV and IR spectroscopy. This is the first report of the production of antifungal compounds by Pediococcus acidilactici LAB 5.
In the present study Silybum marianum L. seeds were fermented using solid-state fer-mentation (SSF) with several lactic acid bacteria (LAB) of Lactobacillus and Pediococcus genera, isolated from spontaneous Lithuanian rye sourdough. A possibility to improve sensory properties (flavour) of Silybum marianum L. seeds using LAB fermentation was investi-gated. The composition of volatile compounds of the unfermented and LAB-fermented seeds of this plant was analyzed using gas chromatography-mass spectrometry (GC-MS). Fermented seeds have shown considerable differences mainly due to the accumulation of higher alcohols. Total amount of phenolic compounds, flavonoids and 2,2-diphenylpicryl-hydrazyl (DPPH) radical scavenging activity of unfermented and fermented seeds were determined spectrophotometrically. The obtained results indicate that Silybum marianum L. seeds are a valuable source of bioactive compounds. The highest content of phenolic com-pounds and flavonoids (4596 and 1346 mg of rutin equivalents (RE) per 100 g, respective-ly) was determined in the seeds fermented with Pediococcus acidilactici KTU05-7 bacteria in solid-state fermentation. Silybum marianum L. seeds fermented with P. acidilactici KTU05-7 and Pediococcus pentosaceus KTU05-9 showed stronger antioxidant activity (1263 and 1041 mg of RE per 100 g, respectively), compared to the unfermented seeds (805 mg of RE per 100 g). The addition of Silybum marianum L. seeds fermented with P. acidilactici KTU05-7 bacteria had the highest effect on the decrease of the bacterial spoilage of bread. The aro-ma compounds from the fermented seeds extracted with supercritical carbon dioxide de-monstrated the highest antimicrobial activity against the tested microorganisms. Ultrasonic pretreatment of the seeds reduced the total amount of microorganisms in the raw material. Microbiological tests revealed that the highest antimicrobial effect was achieved using the solid-state fermentation conditions. This study revealed that fermented Silybum marianum L. seeds are a suitable additive for natural flavouring of baked goods.
The steam distillation-extracted essential oils (EOs) of three aromatic plants from the Kabylie region of Algeria (Eucalyptus globulus, Lavandula angustifolia, and Satureja hortensis) were analyzed by gas chromatography coupled with mass spectrometry (GC/MS). The primary compounds from these EOs were 1,8-cineole (81.70%) for Eucalyptus globulus, 1,8-cineole (37.80%) and Beta-caryophyllene (20.90%) for Lavandula angustifolia, and carvacrol (46.10%), p-cymene (12.04%), and r-terpinene (11.43%) for Satureja hortensis. To test the antibacterial properties of the EOs, agar diffusion and microdilution methods were used for Salmonella enterica serovar Enteritidis CECT 4300. The results revealed that all of the EOs possessed a significant anti-Salmonella activity. The inhibition diameters for Lavandula angustifolia and Eucalyptus globulus were 41.30 and 35.26 mm, respectively, whereas the essential oil (EO) of Satureja hortensis showed a stronger anti-Salmonella activity (51.15 mm) when compared to the two other EOs. The minimum inhibitory concentration values ranged from 1 to 8 uL/mL, and the MIC value of the Lavandula angustifolia EO was the lowest (1 uL/mL). Moreover, the anti-Salmonella activity of the EOs added at various concentrations to liquid whole eggs was investigated, and the results showed that the antibacterial effect is proportional to the quantity of EO added to the product. Based on the observed anti-Salmonella activity, the EOs tested are promising natural alternatives for the preservation of liquid whole eggs stored at 7 ± 1ºC to simulate Algerian refrigeration conditions.
Presented in several types of food, bioactive amines are described as organic bases of low molecular weight. They have vasoactive, psychoactive and toxicological characteristics and constitute a potential health risk. The con-centration of amines formed in foods depends on the type of microorganisms present, the action of decarboxylase enzymes produced by microorganisms on specific amino acids and favorable conditions for enzymatic activity. The presence of these chemical metabolites has been suggested as a quality indicator in routine analyzes for food production and marketing monitoring. The detection of bioactive amines can be performed by chromatographic methods, fluorometric and enzymatic kits. Bioactive amine formation can be prevented mainly through the adoption of good manufacturing practices, but the industry can also use other methods such as temperature control in the production chain, modified atmosphere packaging and food irradiation. This review aims to ad-dress the formation of bioactive amines in foods, emphasizing the formation and classification of these metabo-lites, aspects related to health, acceptable limits, detection methods and control methods used in the industry to ensure food safety and quality. The success of this approach is linked to the importance of bioactive amines as quality indicators, as well as the discussion on the development of methodologies for determining these sub-stances and discussion of acceptable parameters in food.
In the present study, seven thyme species Origanum onites, O. vulgare var. hirtum, O. vulgare var. gracile, O. syriacum, Satureja hortensis, Thymbra spicata, and Thymus vulgaris were used. The essential oils of these plants were obtained by the hydrodistillation method. Antimicrobial activities of the essential oils against microorganisms, including multiple antibiotic-resistant bacteria, were investigated using the disc diffusion method. All the essential oils used in this study were very effective against Gram-positive and Gram-negative bacteria, which included multiple resistant strains. All essential oils tested were especially very effective against Streptococcus pyogenes. The maximum antimicrobial activity was observed with the essential oils of S. hortensis. The antimicrobial activities of the essential oils varied depending on the species. In fact, the essential oils of some thyme species showed different levels of antimicrobial activities. The antioxidant activity results show that the percentage of inhibition values ranged from 28.32 to 94.55 %. Among essential oils, O. vulgare var. gracile oil showed the lowest antioxidant capacity (28.32 %), while S. hortensis showed the highest one (94.55 %). Generally, the data suggest that different thyme species oil possesses useful antimicrobial and antioxidant properties and may be utilized in the food industry and as a dietary supplement.
Influence of Achyranthes japonica Nakai Extract (AJNE) on properties of pork sausages were studied in the present investigation. AJNE was added to sausages alone or in combination with ascorbic acid to obtain a comparative analysis on properties of control and ascorbic acid added-sausages. Results showed that addition of 0.05% AJNE led to a decrease in color L* and whiteness (W), and an increase in color b* of pork sausage samples (p<0.05). Although color a* of pork sausages containing AJNE was not significantly different, ascorbic acid added-sausages were highest amongst other treatments (p<0.05). Sausages containing AJNE had lower non-heme iron values and peroxide value (POV) than control sausages (p<0.05); however, high nitrosomyoglobin content was observed in AJNE added-sausages (p<0.05). Ascorbic acid led to a decrease in residual nitrite concentration of sausages (p<0.05), but no difference was found in AJNE added-sausages. Free radical scavenging analysis showed that AJNE did not affect 1,1-diphenyl -2-picrylhydrazyl (DPPH) activity of sausages, whereas ascorbic acid added-sausages showed relatively higher activity among the samples (p<0.05). Addition of AJNE had no influence on texture properties of sausages. In sensory evaluation, AJNE treatment had significant effects on color (p<0.05), but no significant effects on aroma, flavor, springiness, juiciness, and overall acceptability. In conclusion, the addition of AJNE, as a natural supplement may offer natural antioxidants for pork sausages, and appears to be particularly effective in inducing changes in non-heme iron concentration, POV value and nitrosomyglobin content.
Moulds are the most common cheese spoilage organisms which can lead to economic loss as well as raising public health concerns due to the production of mycotoxins. In this study, 897 lactic acid bacteria (LAB) isolated from different herbs, fruits and vegetables were screened for their antifungal activity in an agar plate overlay assay. Thirty-six isolates had weak activity, 11 had moderate activity and 12 were confirmed as having strong activity. The strong antifungal isolates were obtained from a range of different sources but were all identified by 16S rDNA sequencing as being Lactobacillus plantarum. The antifungal spectra for these 12 isolates were determined against eight other moulds commonly associated with cheese spoilage and all isolates were found to possess inhibition against Penicillium solitum, Aspergillus versicolor and Cladosporium herbarum, but not against Penicillium roqueforti, Penicillium glabrum, Mucor circinelloides, Geotrichum candidum or Byssochlamys nivea. The absence of sodium acetate from MRS agar resulted in no inhibition of Penicilium commune, suggesting the synergistic effect of acetic acid with the antifungal LAB, similarly to that previously reported. To determine their potential as biopreservatives in cheese, LAB isolates were inoculated into cottage cheese prior to the addition of P. commune. All Lb. plantarum isolates were found to prevent the visible growth of P. commune on cottage cheese by between 14 and >25 days longer than cottage cheese that contained either no added LAB or LAB that did not have antifungal activity (Lactococcus lactis, Weissella soli, Leuconostoc inhae and Leuconostoc mesenteroides isolates). The results of this study shows that LAB isolated from various herbs, fruits and vegetables possess antifungal activity and have potential for use as biopreservatives in cheese.
Background:
This study aimed to estimate the effect of the season of milk production and the packaging method on sensory characteristics and some physicochemical indices of fresh curd cheese stored in cooling conditions.
Material and methods:
This study covered three seasons: autumn (October), winter (January) and spring (March/April). The experimental samples were vacuum packed in 50 or 100 μm PE film, or in parchment paper and 50 or 100 μm PE film. The evaluation was made on the day of production of the cheese and after 3, 7, 14 and 21 days of cold storage. The tvarogs were subjected to the sensory evaluation, and also the investigation of moisture content, fat content, acidity, pH, hardness and the percentage of whey leakage was carried out.
Result:
It was found that among the sensory characteristics the deterioration in odour occurred fi rst in the course of storage, regardless of the packaging method applied. The method of packaging exerted no clear effect on moisture content, fat content and hardness of tvarogs. However, wrapping tvarogs additionally in parchment paper increased whey leakage, but also favourably affected cheese structure and consistency.
Conclusions:
Tvarog packed in parchment paper and 100 μm PE film had the most desirable sensory characteristics in the course of storage. The shelf-life of the studied tvarog cheeses was as long as 7 days, regardless of the packaging method used and season of milk production.
Lactic acid bacteria (LAB) are widely employed in food fermentation processes for the biosynthesis of certain important products or metabolites. Fermented food provides plenty of vital nutrients and bioactive components that affect a number of functions of human body in a positive way. Fermented milks can be made more functional by incorporating probiotic strains and furthermore, if they are capable of synthesizing essential biomolecules such as vitamins, enzymes, exopolysaccharides, bacteriocins or bioactive peptides serve into the functional and technological properties of the products. Current paper reviews recent advances associated with biosynthesis of vitamins and enzymes by virtue of LAB and related genera. The outcomes of several studies indicate promising applications at commercial level; however adequate selection of strain is vital to increase the concentration and bioavailability of such biomolecules in fermented foods.
The present study describes chemical composition as well as cytotoxic, antioxidant, and antimicrobial activities of winter savory Satureja montana L. essential oil (EO). The plant was collected from south France mountain, and its EO was extracted by hydrodistillation (HD) and analysed by gas chromatography/mass spectrometry (GC/MS). Thirty-two compounds were identified accounting for 99.85% of the total oil, where oxygenated monoterpenes constituted the main chemical class (59.11%). The oil was dominated by carvacrol (53.35%), -terpinene (13.54%), and the monoterpenic hydrocarbons p-cymene (13.03%). Moreover, S. montana L. EO exhibited high antibacterial activities with strong effectiveness against several pathogenic food isolated Salmonella spp. including S. enteritidis with a diameter of inhibition zones growth ranging from 21 to 51 mm and MIC and MBC values ranging from 0.39–1.56 mg/mL to 0.39–3.12 mg/mL, respectively. Furthermore, the S. montana L. EO was investigated for its cytotoxic and antioxidant activities. The results revealed a significant cytotoxic effect of S. montana L. EO against A549 cell line and an important antioxidant activity. These findings suggest that S. montana L. EO may be considered as an interesting source of components used as potent agents in food preservation and for therapeutic or nutraceutical industries.
The evaluation of antimicrobial activities of Lactobacillus sakei KTU05-6, Pediococcus acidilactici KTU05-7, Pediococcus pentosaceus KTU05-8, KTU05-9 and KTU05-10 strains producing organic acids and bacteriocins like inhibitory substances (BLIS) against undesirable microorganisms in the food industry, were performed using an agar well diffusion assay method. The metabolites of lactic acid bacteria (LAB) inhibited the growth of pathogenic bacteria, belonging to Bacillus, Pseudomonas, Listeria and Escherichia genera in various degrees. The organic acids and BLIS of LAB show fungicidal and fungistatic activities against fungi and yeast such as Fusarium culmorum, Penicillium chrysogenum, Aspergillus fumigatus, Aspergillus versicolor, Penicillium expansum, Aspergillus niger, Debaryomyces hansenii and Candida parapsilosis. 20% of P. pentosaceus KTU05-9 sourdough in a bread recipe suppressed the bread ropiness in artificially contaminated bread by Bacillus subtilis spores, until 6 days storage at 23 °C. Moreover P. acidilactici KTU05-7, P. pentosaceus KTU05-8 and KTU05-10 single cell suspension sprayed on the bread surface, inhibited growing of fungi until 8 days of storage in polythene bags. The presence of BLIS and organic acids by tested LAB is an indication that these bacteria can be used widely in the food industry as bio-preservatives due to their broad inhibition spectrum.
This study examined consumers’ facial reactions elicited by the flavor of orange juice products using an implicit and an explicit measurement approach. The aims of this work were (a) to examine whether facial expressions measured with the Noldus FaceReader technology are a sufficiently accurate measure for differentiating between more or less differing orange juice samples, (b) to elucidate the relation between implicit and explicit facial reactions elicited by orange juices, and (c) to investigate whether implicit and/or explicit facial reactions were able to explain introspective liking ratings on hedonic scales.
The aim of this study was to evaluate the effects of temperature and storage time on the formation of biogenic amines (BAs) in the traditional Czech curd cheese (Olomoucke tvaruzky). Samples were stored for 7 weeks at 5 degrees C and 20 degrees C. BAs were studied as dansyl derivatives by the RP-HPLC method with fluorescence detection, histamine was determined using a photodiode array detector. Physical and chemical properties were analyzed as specified by the Czech National Standard, as were the sensory characteristics (colour, odour, texture and flavour). The major amines found were cadaverine (124-2 413 mg.kg(-1)) and tyramine (117-1 058 mg.kg(-1)), followed by putrescine (75-767 mg.kg(-1)) and histamine (74-411 mg.kg(-1)). Low concentrations of tryptamine, spermine and spermidine were present. Total concentrations of BAs significantly increased with storage time (P < 0.01), depending significantly on temperature (P < 0.01). Total BAs in cheese stored at 20 degrees C compared to 5 degrees C were more than three times higher, reaching 4 600 mg.kg(-1) at the end of storage. The toxicologically critical value of 900 mg.kg(-1) for the sum of histamine + tyramine + putrescine + cadaverine was reached 17 days later in the cheese stored at 5 degrees C compared to 20 degrees C. When stored at 5 degrees C, the samples retained adequate sensory characteristics for the entire safe storage time. The effects of storage conditions on BAs formation are relevant to reducing the risk associated with consumption of cheese high in BAs.
This study aimed to inhibit the growth of Escherichia coli and Clostridium tyrobutyricum, common bacteria responsible for early and late cheese blowing defects respectively, by using novel aqueous extracts obtained by dynamic solid-liquid extraction and essential oils obtained by solvent free microwave extraction from 12 aromatic plants. In terms of antibacterial activity, a total of 13 extracts inhibited one of the two bacteria, and only two essential oils, Lavandula angustifolia Mill. and Lavandula hybrida, inhibited both. Four aqueous extracts were capable of inhibiting C. tyrobutyricum, but none were effective against E. coli. After extracts' chemical composition identification, relationship between the identified compounds and their antibacterial activity were performed by partial least square regression models revealing that compounds such as 1,8 cineole, linalool, linalyl acetate, β-phellandrene or verbene (present in essential oils), pinocarvone, pinocamphone or coumaric acid derivate (in aqueous extracts) were compounds highly correlated to the antibacterial activity.
Biogenic amines (BA) are organic, basic, nitrogenous compounds with biological activity, mainly formed by the decarboxylation of amino acids. BA are present in a wide range of foods, including dairy products, and can accumulate in high concentrations. In some cheeses more than 1000 mg of BA have been detected per kilogram of cheese. The consumption of food containing large amounts of these amines can have toxicological consequences. Although there is no specific legislation regarding the BA content in dairy products, it is generally assumed that they should not be allowed to accumulate. Greater knowledge of the factors involved in the synthesis and accumulation of BA should lead to a reduction in their incidence in foods. This article focuses on the factors that affect BA production, in particular environmental conditions, the microorganisms that produce them, the genetic organization and regulation of the biosynthetic pathways involved, and the available methods for detecting the presence of BA or BA-producing microorganisms in dairy products.
Bacteriocins produced by lactic acid bacteria are gaining increased importance due to their activity against undesirable microorganisms in foods. In this study, a concentrated acid extract of a culture of Lactobacillus sakei subsp. sakei 2a, a bacteriocinogenic strain isolated from a Brazilian pork product, was purified by cation exchange and reversed-phase chromatographic methods. The amino acid sequences of the active antimicrobial compounds determined by Edman degradation were compared to known protein sequences using the BLAST-P software. Three different antimicrobial compounds were obtained, P1, P2 and P3, and mass spectrometry indicated molecular masses of 4.4, 6.8 and 9.5 kDa, respectively. P1 corresponds to classical sakacin P, P2 is identical to the 30S ribosomal protein S21 of L. sakei subsp. sakei 23 K, and P3 is identical to a histone-like DNA-binding protein HV produced by L. sakei subsp. sakei 23 K. Total genomic DNA was extracted and used as target DNA for PCR amplification of the genes sak, lis and his involved in the synthesis of P1, P2 and P3. The fragments were cloned in pET28b expression vector and the resulting plasmids transformed in E. coli KRX competent cells. The transformants were active against Listeria monocytogenes, indicating that the activity of the classical sakacin P produced by L. sakei 2a can be complemented by other antimicrobial proteins.
Lactic acid, a naturally occurring multifunctional organic acid, is a valuable industrial chemical used as an acidulant, preservative in the food industry, pharmaceutical, leather, and textile industries, as well as a chemical feedstock. One of the most promising applications of lactic acid is its use for biodegradable and biocompatible lactate polymers, such as polylactic acid. Lactic acid can be produced either by fermentation or by chemical synthesis but the biotechnological fermentation process has received significant importance due to environmental concerns, use of renewable resources instead of petrochemicals, low production temperature, low energy requirements and high purity. There are numerous investigations on the development of biotechnological methods for lactic production, with an ultimate objective to enable the process to be more efficient and economical. This review discusses the various recent fermentation technologies to produce lactic acid, different microorganisms involved in the production of lactic acid, purification and wide industrial applications of lactic acid.
We are pleased to present the second edition of the Encyclopedia of Dairy Sciences. The first edition was published in 2003 by the Major Reference Works Division of Academic Press, now part of Elsevier Sciences, and it comprised 427 articles. The objective was to satisfy the need for an authoritative source of information for people involved in the integrated system of production, manufacture, and distribution of dairy foods. It was realized from the beginning that a program of revision would be needed to keep the Encyclopedia up to date. This goal has been met in the second edition through 503 articles, of which 121 are new articles and 382 are revised articles.We express appreciation to the Editorial Advisory Board for its role in evaluating articles for needed revision, reviewing new and revised articles, and for help in identifying new topics to be included along with appropriate authors. Likewise, we are grateful for the contributions of the many authors who have either revised their articles or prepared new articles. The main topics related to milk production and dairy technology are addressed in addition to providing information on nutrition, public health, and dairy industry economics including aspects of trade in milk and dairy products. All species that produce milk for human consumption have been included in this work. Some of these species are of regional significance only, but they have been included because of the essential role that their milk plays in the nutrition of people inhabiting various regions of the world. A significant addition to the second edition is four introductory articles addressing the history of Dairy Science and Technology. A synopsis has been prepared for each article in the second edition and will appear with the online listing of the articles in this publication.
Preservation of food and beverages resulting from fermentation has been an effective form of extending the shelf-life of foods for millennia. Traditionally, foods were preserved through naturally occurring fermentations, however, modem large scale production generally now exploits the use of defined strain starter systems to ensure consistency and quality in the final product. This review will mainly focus on the use of lactic acid bacteria (LAB) for food improvement, given their extensive application in a wide range of fermented foods. These microorganisms can produce a wide variety of antagonistic primary and secondary metabolites including organic acids, diacetyl, CO2 and even antibiotics such as reuterocyclin produced by Lactobacillus reuteri. In addition, members of the group can also produce a wide range of bacteriocins, some of which have activity against food pathogens such as Listeria monocytogenes and Clostridium botulinum. Indeed, the bacteriocin nisin has been used as an effective biopreservative in some dairy products for decades, while a number of more recently discovered bacteriocins, such as lacticin 3147, demonstrate increasing potential in a number of food applications. Both of these lactococcal bacteriocins belong to the lantibiotic family of posttranslationally modified bacteriocins that contain lanthionine, P-methyllanthionine and dehydrated amino acids. The exploitation of such naturally produced antagonists holds tremendous potential for extension of shelf-life and improvement of safety of a variety of foods.
Wheat flour dough samples were collected from different bakeries located in Faisalabad city, Pakistan. Spontaneous fermentation of dough samples was carried out for 24 h at 30°C in the laboratory. The isolates were Gram stained and the Gram positive were identified to genus level using morphological, physiological tests. Identification based on classical identification methods and API 50 CH assimilation profiles showed that the lactobacilli contained in sourdoughs belonged to three groups (Lactobacillus brevis, L. plantarum & L. fermentum). Yeasts were also characterized on the basis of morphological and biochemical criteria. Conventional identification methods and API 20 C AUX assimilation profiles revealed that Saccharomyces cerevisiae was the only yeast species present on the sourdoughs.
The nutritional strategies to improve the quality of food products of animal origin are relatively new approach. In this work the solid state fermentation (SSF) and traditional submerged fermentation (TF) with bacteriocin-like inhibitory substances (BLIS) producing lactic acid bacteria was applied for treatment of Satureja montana L. plants (SMP). The effect of fermented SMP additives on ready-to-cook minced pork (RCMP) quality and safety was studied. Viability of LAB in SMP medium significantly (p
Cheese varieties with long ripening periods are prone to form biogenic amines and develop off-flavours. High-pressure processing (HPP), which inactivates microorganisms and enzymes, may be useful in preventing those defects. On this aim, cheeses made from unpasteurized milk were treated at 400 or 600 MPa, after 14 or 21 days of ripening, and their characteristics were compared to those of untreated control cheese throughout a 240-day period. Lactic acid bacteria declined by 2 log units in 400 MPa cheeses and by 6 log units in 600 MPa cheeses after HPP, while Gram-negative bacteria were below detection level in all the HPP-treated cheeses. Aminopeptidase activity was significantly lower in HPP cheeses than in control cheese from day 21 onwards. Hydrolysis of alpha(s)-casein was enhanced in 400 MPa cheeses, but not in 600 MPa cheeses, while a more pronounced hydrolysis of beta-, kappa- and para-kappa-caseins was recorded in all the HPP cheeses from day 60 onwards. Levels of hydrophilic and hydrophobic peptides were higher in HPP cheeses than in control cheese on day 60 and thereafter. Total free amino acids were at lower concentrations in 600 MPa cheeses than in the rest from day 60 onwards. The concentration of total biogenic amines was lower in all the HPP cheeses than in control cheese from day 60 onwards. Flavour quality and flavour intensity of cheese made from unpasteurized milk were not significantly affected by HPP.
The aim of this study was to evaluate the compositional and nutritional potential of methanolic extracts of various parts of Acacia leucophloea Roxb. concerning the chemical composition and antioxidant potential of which limited information is available. Compositional studies indicated carbohydrates as major components in both seed and pods. Despite differences in mineral content among the leaves, pods and seeds, calcium was found in the highest amount and zinc in the lowest. The amino acid profile indicated aspartic acid as the major amino acid and proline as the minor. Among protein fractions, globulin was present in higher amounts than other fractions. Linoleic acid was the major fatty acid detected in the oil from both pods and seeds, while g-tocopherol was the major component of the tocopherol observed from same oil. Moreover, significant antioxidant potential was observed from the extracts of all three parts investigated. The results obtained in this study clearly indicate that A. leucophloea has a sufficient potential for use as a natural antioxidant agent. Further phytochemical studies will be performed for specification of the biologically active principles.
Lactic acid is an important industrial chemical commonly produced through microbial fermentation. The efficiency of acid extraction is increased at or below the acid's pKa (pH 3.86), so there is interest in factors that allow for a reduced fermentation pH. We explored the role of cyclopropane synthase (Cfa) and polysorbate (Tween) 80 on acid production and membrane lipid composition in Lactobacillus casei ATCC 334 at low pH. Cells from wild-type and an ATCC 334 cfa knockout mutant were incubated in APT broth medium containing 3 % glucose plus 0.02 or 0.2 % Tween 80. The cultures were allowed to acidify the medium until it reached a target pH (4.5, 4.0, or 3.8), and then the pH was maintained by automatic addition of NH4OH. Cells were collected at the midpoint of the fermentation for membrane lipid analysis, and media samples were analyzed for lactic and acetic acids when acid production had ceased. There were no significant differences in the quantity of lactic acid produced at different pH values by wild-type or mutant cells grown in APT, but the rate of acid production was reduced as pH declined. APT supplementation with 0.2 % Tween 80 significantly increased the amount of lactic acid produced by wild-type cells at pH 3.8, and the rate of acid production was modestly improved. This effect was not observed with the cfa mutant, which indicated Cfa activity and Tween 80 supplementation were each involved in the significant increase in lactic acid yield observed with wild-type L. casei at pH 3.8.
The content of eight biologically active amines in two groups of smear-ripened cheeses (unwashed-rind and washed-rind) was analysed. The biogenic amine levels were determined after storage at 5 °C in three periods of shelf lifetime: at the minimum durability date; 1 and 2 weeks after this date. The analytical procedure consisted of amine extraction from sample matrix, derivatisation with dansyl chloride and ultra-performance liquid chromatography quantification. The content of biogenic amines and polyamines significantly differed according to the technology of ripening. The cheeses unwashed during ripening had much higher contents of all observed amines and polyamines in comparison with the washed-rind cheeses. The mean content of putrescine, cadaverine and tyramine exceeded 100 mg/kg in unwashed-rind cheeses, while the other amines occurred at lower levels. The content of all detected amines was very low in washed-rind cheeses; no tryptamine, phenylethylamine and histamine were found. The effect of storage on the amine formation was not confirmed.
Eating, drinking and food choices are among the most frequent human behaviours. Although seemingly simple, they are complex behaviours that are determined by many factors and their interactions. The complexity of the research field stresses the necessity to attack problems in an interdisciplinary way. Unfortunately, truly interdisciplinary approaches are still rare in both sensory and consumer research. Although the number of publications has grown rapidly, there is little methodological progress and much repetition of easy mono-disciplinary research. Furthermore, and perhaps worst of all, there is very little influx from the fascinating fundamental insights about human behaviour gained over the last two decennia in physiology and psychology. Thus, findings about intuitive reasoning and the clear demonstration of the unconscious nature of most of our decision making do not seem to have touched sensory and consumer research, although they probably play a more important role in food-related behaviour than anywhere else. Instead, people still strongly adhere to theories like the theory of reasoned action and planned behaviour that are based on the idea of rational and conscious decision making and have come under severe criticism on the basis of their low predictive validity, their weak methodology and their strong theoretical bias. Past behaviour, habit and hedonic appreciation are usually better predictors of actual food choice behaviour than psychological constructs like attitudes and intentions. New insights and especially the realisation that much decision making occurs at a non-conscious level, should lead to a rethinking of the methods used in sensory and consumer research. Situational analysis, observational methods and memory and expectation research have the advantage that they leave the interactive integration of the behaviour determinants with the subject, where it belongs, instead of dissecting and reconstructing it via isolated single factor research.
Four thermotolerant lactic acid bacteria (LAB) were spray dry encapsulated with Acacia gum and inoculated in cooked meat batters. Physicochemical properties (total moisture content, expressible moisture, and cooking stability), pH and acidity, CIE-Lab color, and texture profile analysis were performed at 1 and 8 days of storage at 4 °C. LAB and Enterobacteria counts were determined at 1, 4, and 8 days of storage. Control treatment was inoculated with the same unencapsulated strains as free cells. Total moisture, water activity, and fat release significantly (p < 0.05) increased in spray drying inoculated samples, with no change in expressible moisture. No significantly (p > 0.05) difference in pH and acidity were detected between encapsulated LAB and free cells inoculation. Inoculation of spray dry bacteria significantly (p < 0.05) decreased samples luminosity and redness, with no change in yellowness. In TPA, hardness and springiness had no significantly (p > 0.05) change due to inoculation type, but cohesiveness decreased in encapsulated samples. Inoculation of spray-dried LAB enhanced initial LAB count with a concomitant Enterobacteria reduction. These results suggest that the spray drying encapsulation is an effective way to protect thermotolerant lactic bacteria. These capsules can be inoculated in cooked emulsified meat products in order to ensure their survival before, during, and after processing. Thermotolerant LAB could be employed as bioprotective cultures to improve microbial safety in cooked meat products since the Enterobacteria counts were diminished during storage, enhancing the nutritional values with no major detrimental effect on textural or physicochemical properties of these kinds of foodstuffs.
Lupine has the potential to be a new domestic source of vegetable protein due to its comparable quality to the commonly used soy proteins. However, the bioprocessing that take place in the production of wheat bread with non-conventional flours could play an important role. The wholemeal Lupinus angustifolius and Lupinus luteus flours were fermented by bacteriocin-producing strain of Pediococcus acidilactici. The effect of lupine flour supplementation on wheat bread quality, sensory and safety criteria was studied. The lupine additives significantly decreased the quality of bread. The fermented L. luteus flour (10% of flour basis) had a slightly higher positive effect on the specific volume and crumb porosity (5.4%) and lowering of crumb hardness (9.5%) than those of L. angustifolius. In contrary, consumers rated higher for bread with L. angustifolius sourdough, which contributed to a stronger taste score. The levels of tyramine, histamine and putrescine (32.6–215.8, 20.8–96.7 and 33.7–195.2 mg kg−1, respectively) do not present a health risk for consumers due to their relatively low levels in lupine fermented products. Bioprocessing used for wheat bread production with lupine flour additives could improve the nutritional profile of bread without increasing the risk of biogenic amine formation.
The free amino acids and biogenic amines extracted from normal and late-gassing Cheddar cheeses were derivatized with heptafluorobutyric anhydride and trifluoroacetic anhydride, respectively, before quantification by gas-liquid chromatography. On a microgram scale, twenty amino acids were positively identified in both types of cheese, but only high levels of γ-amino acid butyrate (0.3 to 19.4 mg/g) and small quantities of arginate were found to be associated with “poorly aged” Cheddar cheeses. Histamine (1.54 and 1.22 mg/g) and tyramine (0.32 and 0.43 mg/g) were the bioamines present in highest concentrations in both cheeses.
Enterobacteriaceae (EB, n=149), Lactobacillus (LB, n=162) and Leuconostoc sp. (LC, n=89) and enterococci (EC, n=137), isolated from raw meat (n=65), fermented sausages (n=50) and cheese (n=55) samples, were cultivated in a broth containing precursor amino acids (each 3g/l). After incubation, the liquid culture
was chemically analysed for cadaverine (CAD), putrescine (PUT), histamine (HIS) and tyramine (TYR) formation at pH 5.2 and
at pH 6.7. The majority of EB isolates (147 of 149) was capable of forming >100mg/l of either CAD or PUT. Among the most
frequently isolated species Hafnia alvei and Serratia liquefaciens, formation of >100mg/l HIS occurred, but with low prevalence (1.6 and 6.5%, respectively). Twelve of 149 isolates (8%) were
able to produce more than 10mg/l HIS. One hundred forty-two isolates (95.3%) produced less than 10mg/l TYR, and 7 isolates
(4.7%) 10mg/l to a maximum of 35.3mg/l TYR. For LB+LC, one isolate (Leuconostoc mesenteroides ssp. mesenteroides) formed >100mg/l PUT and one >100mg/l CAD (of all 251 LB+LC isolates 0.4% each). Formation of >100mg/l HIS and TYR was
detected in 3.6 and 19% of the LB+LC isolates, respectively. For the EC isolates, maximum levels for PUT, CAD and HIS were
25.4mg/l, 6.0mg/l and 15.7mg/l, respectively. TYR was formed in quantities of 100–1000mg/l by 47.9% of EC faecalis (n=75), and 59.7% of EC faecium (n=62) isolates. More than 1000mg/l TYR were formed by 50.7 and 35.5% of the isolates, respectively. A low initial pH of
5.2 compared to the initial pH of 6.7 favoured tyramine production by lactic acid bacteria, but was associated with lower
CAD yield by EB.
A considerable intra-species variability in amine formation was observed.
Most data dealing with the biopreservative activity of lactic acid bacteria (LAB) are focused on their antibacterial effects. Food spoilage by mould and the occurrence of their mycotoxins constitute a potential health hazard. Development of biological control should help improve the safety of products by controlling mycotoxin contamination. Data have actually shown that many LAB can inhibit mould growth and that some of them have the potential to interact with mycotoxins.This review summarizes these findings and demonstrates that LAB are promising biological agents for food safety.
Sourdough has been used in bread production for more than 5000 years in order to improve the texture and flavour of baked cereals, and still today sourdough is very important to impart superior flavours to wheat and particularly rye bread. After an introduction into the history of sourdough, results of studies aimed at indicating (i) the influence of the dough and bread recipe, (ii) the regime used in dough fermentation, and (iii) the metabolic activities of sourdough bacteria and yeasts on the final bread aroma are summarized in this review. Based on quantitative results obtained from the same batch of flour, sourdough and rye bread, changes in the concentrations of key bread aroma compounds on the way from flour to bread are highlighted with respect to their contribution to the overall aroma. Based on correlations with the bread recipe, it is discussed how the flour and each technological step influences the final concentrations of selected odorants in the bread.
Microorganisms suitable for food fermentation were examined with regard to their potential to degrade histamine and tyramine. Out of 64 lactic acid bacteria evaluated in this study, 27 degraded histamine and one tyramine, respectively, with low activity. Among 32 strains of Brevibacterium linens and coryneform bacteria, 21 exhibited histamine and tyramine oxidase activity. None of 20 strains of Staphylococcus carnosus tested degraded histamine or tyramine. One strain out of nine strains of Geotrichum candidum degraded tyramine slightly. Among 44 strains of Micrococcus sp. examined, 17 degraded either one or two biogenic amines. In this study Micrococcus varians (M. varians) LTH 1540 exhibited the highest tyramine oxidase activity of all strains tested and was therefore investigated in detail. The enzyme was found to be located in the cytoplasm and was not membrane bound. The reaction end product p-hydroxyphenyl acetic acid was detected by HPLC analysis. An activity staining for the amine oxidase in a native polyacrylamide gel based on the formation of H2O2 during amine oxidation was developed. Resting cells of the strain exhibited optimal tyramine oxidase activity at a pH of 7 at 37-40 degrees C. The enzyme in the cell free extract had a pH optimum between 7-8. The enzyme activity was decreased by NaCl, glucose and hydralazine. Phenylethylamine and tryptamine were oxidized at lower concentrations than tyramine. The potential for amine degradation was not found to be associated with that of formation of biogenic amines, as 23 microorganisms with the ability to metabolise biogenic amines exhibited no decarboxylase activity toward histidine, tyrosine, phenylalanine, lysine or ornithine.
Preservation of food and beverages resulting from fermentation has been an effective form of extending the shelf-life of foods for millennia. Traditionally, foods were preserved through naturally occurring fermentations, however, modern large scale production generally now exploits the use of defined strain starter systems to ensure consistency and quality in the final product. This review will mainly focus on the use of lactic acid bacteria (LAB) for food improvement, given their extensive application in a wide range of fermented foods. These microorganisms can produce a wide variety of antagonistic primary and secondary metabolites including organic acids, diacetyl, CO2 and even antibiotics such as reuterocyclin produced by Lactobacillus reuteri. In addition, members of the group can also produce a wide range of bacteriocins, some of which have activity against food pathogens such as Listeria monocytogenes and Clostridium botulinum. Indeed, the bacteriocin nisin has been used as an effective biopreservative in some dairy products for decades, while a number of more recently discovered bacteriocins, such as lacticin 3147, demonstrate increasing potential in a number of food applications. Both of these lactococcal bacteriocins belong to the lantibiotic family of posttranslationally modified bacteriocins that contain lanthionine, beta-methyllanthionine and dehydrated amino acids. The exploitation of such naturally produced antagonists holds tremendous potential for extension of shelf-life and improvement of safety of a variety of foods.
To develop a probiotic dietary adjunct, soymilk fermented with various combinations of lactic acid bacteria (Streptococcus thermophilus and Lactobacillus acidophilus) and bifidobacteria (Bifidobacterium longum and Bifidobacterium infantis) was subjected to freeze-drying and spray-drying. Survival of the starter organisms during the drying process, subsequent rehydration at different temperatures and during a 4-month period of storage under different storage conditions was examined. After freeze-drying, lactic acid bacteria and bifidobacteria exhibited a survival percent of 46.2-75.1% and 43.2-51.9%, respectively, higher than that noted after spray-drying. Regardless of the drying condition, S. thermophilus showed a higher percentage of survival than L. acidophilus, while B. longum survived better than B. infantis. Further study with soymilk fermented with S. thermophilus and B. longum revealed that the freeze-dried and spray-dried fermented soymilk rehydrated at 35-50 degrees C and 20 degrees C, respectively, was optimum for the recovery of the starter organisms. Both S. thermophilus and B. longum survived better in the freeze-dried than the spray-dried fermented soymilk during storage. A higher percent of survival was also noted for both the starter organisms when the dried fermented soymilk was stored at 4 degrees C than 25 degrees C. Holding the dried fermented soymilk in the laminated pouch enabled S. thermophilus and B. longum to exhibit a higher percentage of survival than in the deoxidant- and desiccant-containing glass or polyester (PET) bottle. Among all the packaging materials and storage temperatures tested, starter organisms were most stable in the dried fermented soymilk held in laminated pouch and stored at 4 degrees C. Under this storage condition, S. thermophilus and B. longum showed a survival percentage of 51.1% and 68.8%, respectively, in the freeze-dried fermented soymilk after 4 months of storage. Meanwhile, S. thermophilus and B. infantis in the spray-dried fermented soymilk showed a survival percent of 29.5% and 57.7%, respectively.
To investigate antifungal activity produced by lactic acid bacteria (LAB) isolated from malted cereals and to determine if such LAB have the capacity to prevent fungal growth in a particular food model system.
The effect of pH, temperature and carbon source on production of antifungal activity by four LAB was determined. Pediococcus pentosaceus was used to conduct a trial to determine if it is feasible to eliminate Penicillium expansum, the mould responsible for apple rot, using an apple model. Penicillium expansum was incapable of growth during the trial on apple-based agar plates inoculated with the antifungal-producing culture, whereas the mould did grow on apple plates inoculated with an LAB possessing no antifungal activity.
Partial characterization of the antifungal compounds indicates that their activity is likely to be because of production of antifungal peptides. The trial conducted showed that the antifungal culture has the ability to prevent growth of the mould involved in apple spoilage, using apples as a model.
The ability of an LAB to prevent growth of Pen. expansum using the apple model suggests that these antifungal LAB have potential applications in the food industry to prevent fungal spoilage of food.
Seventeen additional minor ecdysteroid compounds were isolated and identified from the roots of Leuzea carthamoides (Wild.) DC. Eight of them are new phytoecdysteroids: carthamoleusterone (13) is a new side-chain cyclo-ether with five-membered ring; 14-epi-ponasterone A 22-glucoside (12) is a rare and unusual natural 14 beta-OH epimer; 15-hydroxyponasterone A (11) is also new and rare with its C-15 substituted position, as well as 22-deoxy-28-hydroxymakisterone C (18) possessing secondary hydroxyl in position C-28 and 26-hydroxymakisterone C (20) with hydroxy groups in positions 25 and 26. New are also 1 beta-hydroxymakisterone C (21) and 20,22-acetonides of inokosterone (8) and integristerone A (10). Series of already known ecdysteroids: ecdysone (1), 20-hydroxyecdysone 2- and 3-acetates (3 and 4), turkesterone (6), inokosterone (7), 24-epi-makisterone A (14), and amarasterone A (22) are reported here as new constituents of L. carthamoides. Seven earlier reported Leuzea ecdysteroids: 20-hydroxyecdysone (2), ajugasterone C (5), integristerone A (9), 24(28)-dehydromakisterone A (15), 24(28)-dehydroamarasterone B (16), (24Z)-29-hydroxy-24(28)-dehydromakisterone C (17) and makisterone C (19) are also included because they are now better characterized.
Chemical composition and antimicrobial activity of volatile components from capitula and aerial parts of Rhaponticum acaule DC growing wild in Tunisia
- O Boussaadaa
- S Ammarb
- D Saidanab
- J Chriaac
- I Chraifb
- M Daamid
Boussaadaa, O., Ammarb, S., Saidanab, D., Chriaac, J., Chraifb, I., Daamid, M., et al.
(2008). Chemical composition and antimicrobial activity of volatile components
from capitula and aerial parts of Rhaponticum acaule DC growing wild in
Tunisia. Microbiological Research, 163, 87e95.
Internet access http
- Fao Who
FAO/WHO expert Committee on Food Additives. (1967). Internet access http://
www.inchem.org/documents/jecfa/jecmono/40abcj44.htm.
Influence of polysorbate 80 and cyclopropane fatty acid synthase activity on lactic acid production by Lactobacillus casei ATCC 334 at low pH
- Broadbend
Chemical composition and antimicrobial activity of volatile components from capitula and aerial parts of Rhaponticum acaule DC growing wild in Tunisia
- Boussaadaa
Bioactive amines: aspects of quality and safety in food
- Rodriguez