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Infant milk formula (IMF) is fortified milk with composition based on the nutrient
content in human mother's milk, 0 to 6 months postpartum. Primary ingredients include
bovine milk and/or whey, lactose, vegetable oils and vitamin/mineral premixes. Extensive medical and clinical research has led to advances in the nutritional quality of infant formu...
Citations
... Additionally, the D [4,3] value for infant milk formula was found to be 155.4 microns by Murphy et al. [42]. Powder flowability is directly influenced by the drying process and is affected by both the size distribution and interparticle relationships [43]. ...
Alcea rosea, known as hollyhock, is an ornamental dicot flower in the Malvaceae family, and it has been used for different purposes, ranging from traditional medicine to food applications, through the use of its leaves, roots, and seeds. The hollyhock flowers possess several properties, including a diuretic, cooling, demulcent, emollient, febrifuge, and astringent effects. Hollyhock flowers were commonly included in a traditional medicine formulation for hypoglycemic or hypolipidemic treatments. Along with its use in traditional medicine, it has also been considered a valuable ingredient in some traditional food preparations; however, the processing of hollyhock into a new food product has not been studied. Accordingly, this study aimed to evaluate the production of a new product, a milk-based Hollyhock (Alcea rosea) powder, and its powder product characterization via particle size, water activity, density, flowability, etc., in addition to the determination of its chemical composition (with 5.73% ash and 29.12% protein). In this paper, we report the application of spray-dried milk-based hollyhock flower extract to produce a new ready-to-drink product of this medicinal plant for food sustainability.
... Particle size Skim milk powder particle size parameters are shown in Table 3. High-heat-treated skim milk powder was observed to have significantly higher (P < 0.05) D [4,3] and D 90 and D 50 values than other powders. This may be due to the high apparent viscosity of HHSMC, which results in coarser particles during atomisation (Murphy 2015). A similar result was reported by Crowley et al. (2014) for MPC60 compared with MPC80, MPC85 and MPC90. ...
The aim of this study was to investigate the effect of heat treatment on the physicochemical properties of skim milk concentrate (SMC) and spray‐dried skim milk powder (SMP). The apparent viscosity of high‐heat‐treated SMC was higher than medium‐heat‐treated, low‐heat‐treated and control SMC. The results obtained in this study provide novel insights into the effect of heat treatment on the subsequent powder properties and demonstrated that high‐heat‐treated SMP had significantly higher moisture content, aw, particle size, b* value and the absence of crystallisation than the medium‐heat‐treated, low‐heat‐treated and control SMP samples. Increasing the intensity of heat treatment resulted in different reconstitution behaviours at the same %TS content and wettability. Effect of heat treatment on the apparent viscosity of skim milk concentrate and the physicochemical properties of spray dried skim milk powder.
... There is less fouling in direct heat treatment systems compared with indirect systems, as there is no interface between the heating medium and product where localised heating, protein denaturation and fouling typically take place (Akkerman et al., 2016;Karayannakidis et al., 2014;Murphy, 2015). Truong et al. (2017) found no significant fouling in a direct steam injection system after 8 h of processing whole milk at both 80 and 120 kg h À1 with temperatures of 75 C for preheating and 95 C for final heating being applied. ...
The heat treatment (HT) of milk and dairy ingredients for the purpose of powder manufacture is a complex and multifaceted area, with many factors influencing microbial quality, process efficiency (e.g. product composition, processing equipment and operating parameters) and end-powder functionality (e.g., heat stability, powder rehydration, gelation, etc.). One primary area of research is the mechanisms responsible for heat-induced viscosity development, mainly due to its role in fouling of processing equipment. Development of means of predicting viscosity increase due to thermal heat treatment have proven beneficial and are discussed herein. The review also highlights scientific areas of interest where limited published information exists, and perhaps should be explored in the near future.
Milk protein concentrate (MPC 80), skim milk powder, acid whey protein concentrate (aWPC 35), cheese whey protein concentrate and isolate (cWPC 35 and cWPI) were assessed for suitability in IF applications with total solids similar to commercial ready-to-drink applications. Serum-phase compounds including phosphate, citrate and chloride in casein-rich streams, especially aWPC 35, played an important role in controlling whey protein thermal aggregation. Replacing cWPC 35 with cWPI improved protein stability at UHT temperatures, indicating that removal of minerals from whey protein streams could increase thermal stability of formulations. At HTST temperatures (95 °C), lactose appeared to have a protective effect against protein denaturation. At 140 °C, however, lactose contributed to cascading Maillard reactions triggering complete protein destabilisation; this occurred most rapidly in MPC 80 formulations that were comparatively low in serum-phase calcium-binding species (phosphate and citrate). These findings highlight how innate minerals and lactose impact protein stability during IF manufacture.
Milk concentrate (MC) viscosity is a key process control parameter in the manufacture of dairy based powders that affects both process efficiency and powder functionality. If the viscosity of MC is too high, various processing issues can arise, i.e., pump blockages, fouling, poor atomisation, product rework and production downtime. Viscosity of MC is dependent on various intrinsic (e.g., total solids content, protein: lactose ratio, mineral profile, pH) and extrinsic (e.g., temperature, agitation, high shear) parameters. It is therefore necessary to understand the effects of these parameters on the viscosity of MC to maintain an optimal process. This review focuses on outlining the parameters that affect the viscosity of MC and recent advances in processing strategies to reduce viscosity of MC prior to spray drying during powder manufacture.
