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Cameroon administrative and agro-ecological map market, at least fifteen women (traders and household users of TAS) were questioned. Questions were asked to only one woman at the time and altogether, 204 women from 13 markets of survey areas have answered the totality of the questionnaire. 20 (9.8%) women were of less than 30 years old, 96 (47.1%) women were between 31 and 60 years old, and 13 (6.4%) women were above 60 years old. 74 women (36.3%) did not indicated their age, but generally, they were estimated as belonging to the two first groups. 56.3% of women originated from Western highlands zone, 4.9% from high Guinea savannah zone, 28.5% from Sudano-sahelian zone, and 6.4% from Humid Forest zone.
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Aims: Determine the variability and usages of Traditional Alkaline Salts (TAS) used in Africa, specifically in Cameroon. Place and Duration of the Study: This study was done in different agro-ecological areas of Cameroon between January and August 2015. Methodology: Individual interviews of women (204) found in markets of different Agro-ecological...
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Context 1
... survey has been carried out in eight localities (Pitoa, Garoua, Ngaoundéré, Yaoundé, Douala, Bafoussam, Mbouda and Bamenda) located in all the agro-ecological zones of Cameroon [48] (Fig. 1). The choice of these survey areas was based both on the cosmopolite character of big towns (Douala and Yaoundé) where people from different ethnic origins are found, and on local usage habits of TAS in some towns (Pitoa, Garoua, Ngaoundéré, Bafoussam, Mbouda and Bamenda). In each locality, survey was carried out in markets, each market ...
Citations
... In fact, West African people appreciate potash as prophylaxis to an array of health problems (e.g., asthenia, osteoporosis, cardiovascular diseases, and gastrointestinal disorders) and a source of alkaline taste. 8 In many parts of the world, traditional and non-conventional foods such as Zamnè have become an integral part of human diets. However, the estimation of their contribution to nutrient intake suffers considerably from the lack of data on their composition and the poor understanding of the preparation processes. ...
Zamnè is a wild legume and a famine food that attracts interest for its health benefits and has become a delicacy in Burkina Faso. This study aimed to determine the nutritional quality of the traditionally cooked Zamnè, appreciate the effectiveness of the traditional cooking process, and compare the properties of the traditionally used cooking alkalies (i.e., potash or plant ash leachate and sodium bicarbonate). Yet, as shown, the traditional cooking of Zamnè is a very aggressive process that results in a high disintegration of the cell walls and membranes and leaching of most water-soluble constituents and nutrients (i.e., free amino acids, soluble nitrogen, sugars, soluble dietary fibers, and soluble phenolics). In addition, the extensive boiling and the cooking alkalies induced the sequestration of calcium, iron, magnesium, and zinc, significantly impairing their bioaccessibility. Despite the difference in the modus operandi of the cooking alkalies, there was no significant difference in the cooking outcomes. The traditionally cooked Zamnè presented high dietary protein (4.8 g), lipid (3.3 g), fibers (6.7-7.7 g), and metabolizable energy (63-65 kcal) contents (per 100 g fresh weight). Most antinutritional factors (i.e., non-protein nitrogen, tannins, and trypsin inhibitors) were eliminated. The proteins were relatively well preserved despite the aggressive alkaline processing and demonstrated an appreciable digestibility (75%) and predicted PER (1.5) and a fairly balanced essential amino acid composition, which should completely meet the requirements for adults. The lipid content and composition were also well preserved and contained predominantly linoleic (C18:2n-6), oleic (C18:1c9), stearic (C18:0), and palmitic (C16:0) acids (33, 34, 10, and 15% total fatty acids, respectively). Overall, though extensive alkaline cooking seems straightforward option to overcome the hard-to-cook problem of Zamnè, processing alternatives might be useful to reduce nutrient losses, improve the digestibility of the final product, and capture its full nutritional values.
... However, Burkinabes highly appreciate the traditionally cooked Zamnè as the development of its unique taste is believed to be related to the cooking alkali (i.e., potash) and process. In fact, West African people appreciate potash as prophylaxis to an array of health problems (e.g., asthenia, osteoporosis, cardiovascular diseases, and gastrointestinal disorders) and a source of alkaline taste (Ngoualem et al., 2019). ...
People in the arid and semi-arid tropics (i.e., Aridoamerica, outback Australia, South America, Southern Asia, and sub-Saharan Africa) are the poorest and most vulnerable to food insecurity in the world, representing more than 80% of undernourished people globally and one of the major handicaps to the sustainable development agenda. However, the vulnerability to food insecurity in those areas remains quite paradoxical, considering that those areas hold the richest biodiversity for food and the largest arable lands in the world. Suffice it to say, people in the arid and semi-arid tropics still have insufficient knowledge and mastery of their environment.
In line with the concerted incentives to document, safeguard, and valorize natural or wild food resources, this PhD provides an unprecedented insight into the food and nutritional potential of Acacia s.l. products and particularly the seeds from the segregate genus Senegalia. Overall, this study may help to improve environmental stewardship in the arid and semi-arid tropics and foster several Sustainable Development Goals, including goal 1 (reduce poverty), 2 (end hunger), 3 (promote health and wellbeing), 12 (ensure sustainable consumption and production patterns), 13 (combat climate change and its impacts), and 15 (preserve ecosystems).
... Their chemical composition shows that they are a mixture of minerals, mainly of salts and oxides (CaO, K 2 O, FeO, Fe 2 O 3 , MgO, and P 2 O 5 ), and thus of anions (OH -, CO 3 2-, HCO 3 -, SO 4 2-, S 2-, CN -, F -, Cland H 2 PO 4 -) and cations (Na + , Ca + , Fe 2+ /Fe 3+ , K + , Mg 2+ , Li + , V x+ , B x+ , Mo x+ , Al 3+ , Mn x+ ), Ni 2+ , Co 3+ , Cd 2+ , Pb 2+ , Zn 2+ , Cu 2+ and Cr 3+ ) (the letter x in superscript for some cations is used for multivalence cations that the ionic form analysed was not provided in the corresponding studies) [5-9, 12, 13, 17-19, 21, 32-34]. Each type of solid TAS exists in market stalls in a variety of colours ("black" and "white" for lake deposits; "black", "greyish", "white", "cream yellow" and "light brown" for plant-based ashes) [14,15,21,25,26]. For any given functionality, for the same type of TAS, users have a preference that is oriented toward a given colour. ...
... For any given functionality, for the same type of TAS, users have a preference that is oriented toward a given colour. This preference is based on the fact that, for the same type of salt, the same quantity of its respective colours has variable effects when used at the household scale [25]. The differences observed in the usages of these salts show that they have different chemical compositions and physicochemical properties. ...
... For plant-based salts, their difference in efficiency could be due to plants or plant parts used as well as conditions occurring during the burning process [14,15,25,26]. Moreover, some studies involving the use of TAS (without any mention of their colour) have revealed the presence of heavy metals (lead and cadmium) in variable quantities [5-7, 13, 33] and such determinations are vital in order to restrict their use in food preparations. ...
Lake deposits and plant-based ash salts are food additives used in a variety of food preparations throughout the world. They exist in many colours and are found in market stalls in many countries. In the literature, they have been named traditional alkaline salts (TAS). Their colours (as identified by users) are their major quality determinant and are associated with their efficiency when used in food preparations. Up to now, no relationship has been established between their colours and their chemical composition and/or physico-chemical properties. Lake deposits (sampled in Cameroon and Nigeria), "white" plant-based ashes and evaporites of plant-based ash filtrates (sampled in Cameroon) found from the market have a buffer behaviour (pH of 10 and 11) while "green" and "black" plant-based ashes do not (pH = 12 to 14). The buffer behaviour is due to the simultaneous presence of carbonates and bicarbonates, combined with the absence of oxides, the pH of the resulting solutions was increased with increasing carbonates/bicarbonates ratio. The colours of evaporites of plant-based ash filtrates are similar (less than 6% of difference) in their chemical composition (sodium, potassium, carbonates and bicarbonates) and physico-chemical properties while the other TAS are not. "White" lake deposits have higher major ions (sodium, potassium, carbonates and bicarbonates) content than the "black" ones. There is always a toxicity risk (lead and cadmium) associated with the use of plant-based ash salts and sometimes "black" lake deposits while there is not a toxic risk associated with the use of the "white" colour of lake deposits. "Black" lake deposits sampled in Abuja, Nigeria have one and a half times more cadmium and lead than those sampled all over Cameroon when they contain these metals.
... Till date, most studies on traditional plant based food salts have been focused on their chemical composition [23,24], their effect on the nutritional quality of foodstuffs [19,25,26], their effect on the taste of food preparations [19], and their toxicological effect [12,27]. e variability and functionalities of traditional salts used in traditional African food preparations were studied by Ngoualem et al. [28] while Ngwasiri et al. [29] studied the effect of the incorporation of crude extract from Ficus carica seed peels into crude extract from plantain peel ash to improve on its functional properties and the sensory properties of the yellow achu soup. Furthermore, Franklin et al. [30] reviewed the chemistry and functionalities of lake deposits and plant-based salts used in food preparations. ...
In Cameroon, agrofood waste biomass such as peels of Musa paradisiaca and Musa acuminate is being valorized using various traditional processing methods to produce a traditional functional food salt, potash, locally called nikkih. Nikkih has been reported to have varying physicochemical and functional properties, which negatively affect the quality and stability of food prepared using it. This work aims at evaluating the effect of traditional process methods on the physicochemical and functional properties of nikkih produced from these peels in view of the optimization of the process. The peels were preprocessed using two methods: boiling at 90oC before drying and direct drying of raw samples. All samples were dried and combusted to ash at varying temperatures of 250oC, 300o C, and 350oC and times of 30 min, 60 min, and 90 min. The ash obtained was dissolved in varied volumes of water, filtered to obtain the nikkih. Yellow achu soup was prepared through the dry gum method using water and read palm oil, with nikkih as emulsifier. The physicochemical and functional properties of nikkih on yellow achu soup were evaluated using standard methods. The ash yield ranged from 10.62 ± 0.12% to 7.10 ± 0.05%, with the raw samples combusted at 300⁰C and 250⁰C having the highest and lowest values respectively. The pH of nikkih ranged from 10.95 ± 0 to 12.01 ± 0.056 while potash content ranged from 32.45 ± 0.905% to 72.29 ± 1.31%, with the highest and lowest values obtained from the raw sample combusted at 250⁰C and the boiled samples combusted at 350⁰C respectively. Alkaline content ranged from 61.7 ± 0.141% to 52.8 ± 0.141%, with boiled M. acuminate combusted at 350⁰C having the highest value and the lowest from raw M. paradisiaca combusted at 250⁰C. The foaming capacity and foam stability ranged from 6.9 ± 0.01% to 16.07 ± 2.51% and from 3.20 ± 0.07% to 11.205 ± 2.39% for M. acuminate and M. paradisiaca respectively. The emulsification index ranged from 85.62 ± 0.09% to 86.67 ± 1.141% after 24 hrs and from 26.0 ± 0.94% to 27.02 ± 2.390% after 48 hrs, with the highest value from the raw M. acuminate combusted at 350oC and the lowest from that combusted at 300⁰C. The potash source, pretreatment method, combustion conditions, and dilution factors all had an effect on the physicochemical and functional properties of nikkih.
1. Introduction
Food loss and waste is recognized as a serious threat to food security, the economy, and the environment [1]. Despite various measures taken to ensure the notion of zero waste so as to attain sustainable food production and consumption [2, 3], agrofood waste management still remains a serious problem in many countries [4, 5]. The agrofood industry generates high amounts of byproducts and waste, which account for more than 50% of fresh fruit and at times have a nutritional or functional value higher than the final products [6]. These byproducts and waste, constituting mainly of peels, trimmings, stems, shells, bran, and seeds, are regarded as emerging sustainable agricultural issues as many of these biomaterials are underutilized and end up in municipal landfills where they create serious environmental, economic, and social problems [7–9]. The environmental and economic impact of agrofood waste is associated with the depletion of natural resources used for its production and the costs associated with its disposal (Moron, 2016). These two problems can be solved within the context of the circular bioeconomy by valorizing these wastes for the production of value-added biochemical products or ingredients for the agrofood industry [10, 11]. The exploitation of food byproducts and waste generated in the poor regions of the world for the formulation of novel foods or food ingredient will directly benefit the local communities [12], thereby enhancing food security and contributing to the development of the circular bioeconomy.
In many regions in Cameroon, particularly in the North West and West Regions, for example, the peels of Musa paradisiaca and Musa acuminate are being valorized traditionally for the production of a traditional functional food salt, potash, locally called ‘nikkih’. Nikkih constitutes the crude brownish or blackish extract produced traditionally by leaching the ashes of combusted agrofood waste with water to obtain a potassium-carbonate-rich crude bioextract [13, 14]. Their chemical composition shows that they are a mixture of salts and, thus, are made of cations and anions; the major cation is generally sodium or potassium whereas the major anions are generally carbonates, bicarbonates, sulfates, and chlorides [15–17]. These biobase functional plant extracts are fast replacing the common lake salt called “kangwa”, as they are regarded as cheaper, safer, less-toxic, and readily available from food waste biomass and their production from waste biomass contributes to environmental protection. Nikkih is now used in the preparation of a variety of foods due to its functional properties since it serves as emulsifier, tenderizer, thickener, seasoning, potentiating adjunct, and preservative [18]. The functionalities of nikkih have been attributed to the alkalinity of the aqueous solution [19]. With respect to its functionality, the ability to reduce cooking time has been studied [20, 21].
Traditionally, nikkih is produced using two methods of pretreatment of the peels of M. paradisiaca and M. acuminate: boiling of the raw peels before drying or direct drying of the peels. The drying process is followed by combustion of the biomass to produce ash and leaching of the ash with water to obtain a crude brownish or blackish extract. This potassium-carbonate-rich crude extract [13, 14] produced in an indigenous manner contains a lot of impurities responsible for its color [22] and has been reported to have varied functional properties when used in food as an emulsifier and stabilizer, especially in yellow achu soup. Yellow achu soup is an emulsion of crude palm oil in water, stabilized by kanwa and more recently by nikkih, in which a mixture of ground local spices is added. The soup is eaten with a traditional delicacy called achu, obtained by pounding the tubers of Colocasia esculenta. In the traditional method of nikkih production, the biomass pretreatment methods vary as a function of the source of the peels along the food value chain: boiling of the Musa sp. with peels before drying or peeling off the peels to dry directly. On the other hand, the combustion and extraction are done under undefined temperature and time process conditions.
Till date, most studies on traditional plant based food salts have been focused on their chemical composition [23, 24], their effect on the nutritional quality of foodstuffs [19, 25, 26], their effect on the taste of food preparations [19], and their toxicological effect [12, 27]. The variability and functionalities of traditional salts used in traditional African food preparations were studied by Ngoualem et al. [28] while Ngwasiri et al. [29] studied the effect of the incorporation of crude extract from Ficus carica seed peels into crude extract from plantain peel ash to improve on its functional properties and the sensory properties of the yellow achu soup. Furthermore, Franklin et al. [30] reviewed the chemistry and functionalities of lake deposits and plant-based salts used in food preparations. All these studies basically highlighted the relationships among chemical composition and physicochemical properties of traditional alkaline salts when used in solution as well as their functionalities. Studies attempting to evaluate the effect of the traditional process methods on the physicochemical and functional properties of this traditional food salt are very scarce.
The physicochemical and functional properties of traditional plant based food salt seem to be related to the nature of plants used for their preparation and the biomass processing conditions [31]. There are numerous reports of ash salts having been produced all over South and Central America [32] and in Africa, including Cameroon [30], but reports on the effect of processing methods on the physicochemical and functional properties of this traditional food salt are scarce. Processing factors such as the number of cycles and duration of filtration have been reported to affect some properties of the salt such as its color [30]. In addition, the degree of compaction of banana/plantain peels and stalks during combustion has been reported to determine the color of the salts: green with low compaction or black or white with high compaction. Phanice et al. [33] reported the effect of the transformation, preparation method, storage conditions, and time on Iodine and Iron (II) present in Reed Salt, a traditional plant based salt in Kenya. The valorization of these biomass into quality and safe functional traditional food salt as such faces a certain number of problems like differences in the biomass pretreatment methods, boiling of biomass before drying and direct drying of biomass, and the combustion conditions.
Biomass pretreatment and the different process conditions during the thermochemical process, such as temperature, reaction time, heating rate, and pressure, have been reported to affect the quality of intermediates and the products generated [34]. Currently there are scarcity of information on the effect of the traditional pretreatment and processing methods used for nikkih production on its functional quality and the sensory property of yellow achu soup. From these findings, checking the influence of the process method and process factors on the physicochemical and functional properties of traditional food salts appears as research questionable issues. This will help in the determination of the best process conditions for the production of nikkih with optimal functional and sensory qualities. This research is therefore aimed at studying the effect of the two traditional process methods on the physicochemical and functional properties of food grade lime (nikkih) obtained from waste biomass peels of Musa paradisiaca and Musa acuminate.
2. Materials and Methods
2.1. Materials for Nikkih and Yellow Achu Soup Preparation
Fresh unripe Musa paradisiaca and Musa acuminate peels were obtained from a local market in Bambili-Bamenda and transported to the laboratory in a flask at 4⁰C where it was stored in a refrigerator at 4⁰C before usage so as to avoid any ripening. Red palm oil and all other spices for the preparation of the yellow achu soup were obtained from the Bambili market.
2.2. Pretreatment of Musa paradisiaca and Musa acuminate Peels
The waste biomass peels were pretreated following the two traditional methods commonly applied in the North West region of Cameroon. Unripe Musa paradisiaca and Musa acuminate peels were washed with clean running tap water to remove all debris. The peels were separated into two portions each, which were subjected to two pretreatment methods as locally done, before drying and combustion to produce ash. One portion of the peels from Musa paradisiaca and Musa acuminate was maintained raw (RS) while the second portion was boiled (BS) for 90 mins at 90oC. This was followed by drying of all the portions separately in a food dehydrator at 70oC for 48 hrs. The dried peels were weighed and stored in dry airtight polyethylene bags for further processing.
2.3. Combustion of Musa paradisiaca and Musa acuminate Peels for Ash Production
The waste biomass peels were combusted following the traditional method commonly applied in the North West region of Cameroon, with a variation of the combustion temperature and time. A known weight of the pretreated dried M. paradisiaca and M. acuminate peels was combusted in a furnace to ash using different combustion temperature-time combination of 250oC, 300oC, and 350oC for 30 mins, 60 mins, and 90 mins, respectively. The ash was then collected, weighed, and stored in dried airtight containers for further processing and analyses.
2.4. Preparation of the Liquid Extract (Nikkih)
The liquid crude extract from the ashes of M. paradisiaca and M. acuminate peels was produced as described by Kumar [35] and illustrated in Figure 1. 100 g of the ashes was weighed and placed in separate bottles and varied volumes of water of 500 ml, 1000 ml, and 1500 ml at 80oC were measured and poured in the respective bottles. The bottles were corked, mixed vigorously, and allowed to stand for 12 hours. The resulting clear liquid solution was filtered into well labelled plastic bottles using Whatman No. 41 filter paper.
... Recently, studies on toxicological and biochemical effects of Trona in rats have indicated a potential hepatotoxic effect on liver oxidative stress and function with no short-term toxic effect on the renal function [12]. In the northern part of Nigeria, Trona is consumed through the following exposure pathways: ingestion when used as a cooking ingredient in vegetable soups, inhalation when snuffed together with tobacco in their powdery forms, ingestion when used as a major food supplement, ingestion when used as a medicine in humans for various ailments, ingestion when used as an enhancer of the quality and quantity of breast milk after delivery, ingestion when used as a tenderiser, ingestion when used as a flavouring agent, ingestion when used as a food preservative as well as an improver of protein digestibility of cowpea [9,[13][14][15][16][17]. Although, literatures reported the elemental, physicochemical, biochemical and physiological effects of Trona [12,18,19], little information has been reported with regards to its radiological content. ...
Mined Trona is a naturally occurring inorganic salt that is consumed by humans for diverse purposes in Nigeria. Due to the increase in consumption rates of these salts following a renewed government interest in solid minerals exploration and exploitation, it is imperative to assay its radiological content. Reconnaissance survey revealed that the most commonly used Trona varieties were: of the identified Trona varieties were purchased from markets within Zaria, Nigeria. The samples were analysed using NaI (Tl) gamma ray spectrometry system. Radium equivalent activity (Ra eq), annual effective dose (AED), Internal and Alpha hazard Indices (H in and I α) and total cancer risks (TCR) were used to assess the radiological safety of its consumption. The activity concentration of 238 U (226 Ra); 232 Th and 40 K varied widely and had an average ± error values of 42.904 ± 4.54 Bq/kg, 11.96 ± 1.41 Bq/kg and 455.28 ± 10.56 Bq/kg respectively. Ra eq , AED, I α , H in and TCR were estimated at 95.07 ± 63.10 Bq/kg, 68.52 ± 52.53µSv/y, 0.21 ± 0.23, 0.37 ± 0.27 and (390.57 ± 299.44) ×10 À 06 respectively; which were by far less than the US EPA and UN SCEAR acceptable thresholds. It was established that the threshold consumption rate is 40 Kg/year and any value slightly higher than the threshold values will be associated with a significant radiological health risk. Therefore, at the present consumption rate of Trona in Nigeria, there is no cause for radiological concern.
... This "traditional alkaline salt" is known to have an improving effect on the texture of sauces made with okra or nkui (Ngoualem, Nguimbou, & Ndjouenkeu, 2019 ...
... 34-36) in which the other ingredients, including "potash," have been added, are the most stringy. The presence of this alkaline and mineral-rich ingredient, known for its effect on okra texture (Ngoualem et al., 2019), certainly contributes to the high level of stringiness observed for these samples. Table 3 shows that water content has a significant and dominant linear effect on all three parameters and a significant quadratic effect on K and n. ...
Okra (Abelmoschus esculentus) is one of the ingredients widely used in African gastronomy because of the unique slimy texture it gives to sauces. However, processing and formulation can affect the textural and rheological properties of these sauces, leading to unacceptable quality for the African consumer. The aim of this study was to select the instrumental measurements best enabling i) characterization of the rheology and texture of slimy sauces prepared from okra and ii) monitoring its evolution during the preservation process. 37 slimy suspensions (sauces and purées) were measured with 16 rheological and textural parameters. A Principal Component Analysis revealed that flow consistency index K and flow behavior index n were well correlated with visco‐elastic, adhesive and shear thinning properties, and that stringiness was well correlated with elongational, cohesive and ductile properties. These two sets of measurement methods are sufficient to characterize their rheological and textural properties, and necessary to discriminate them according to their process and formulation. This article is protected by copyright. All rights reserved.
Lake deposits, plant-based ashes, filtrates and evaporites or alkaline salts are used traditionally in food preparations by local populations in Africa, Asia, South America, and Oceania. Depending on the context, traditional alkaline salts are used to reduce cooking times, improve rheological characteristics of starchy doughs, maintain the color of vegetables, improve the viscosity of sticky vegetables, and act as emulsifiers. This review highlights some of the relationships among chemical composition and physicochemical properties of traditional alkaline salts when used in solution as well as their functionalities. In addition, their potential toxicity and physiological effects are explored, which might lead to a better understanding of some previously unexplained functionalities and future trends in research, such as their impact on human health.
