Effects of milk supplementation with skim milk powder, whey protein concentrate and sodium caseinate on acidification kinetics, rheological properties and structure of nonfat stirred yogurt

Abstract

a b s t r a c tMilk supplementation with milk proteins in four different levels was used to investigate the effect on acidification and textural properties of yogurt. Commercial skim milk powder was diluted in distilled water, and the supplements were added to give different enriched-milk bases; these were heat treated at 90 C for 5 min. These mixtures were incubated with the bacterial cultures for fermentation in a water bath, at 42 C, until pH 4.50 was reached. Chemical changes during fermentation were followed by measuring the pH. Protein concentration measurements, microbial counts of Lactobacillus bulgaricus and Streptococcus thermophilus, and textural properties (G 0 , G 00 , yield stress and firmness) were determined after 24 h of storage at 4 C. Yogurt made with milk supplemented with sodium caseinate resulted in significant properties changes, which were decrease in fermentation time, and increase in yield stress, storage modulus, and firmness, with increases in supplement level. Microstructure also differed from that of yogurt produced with milk supplemented with skim milk powder or sodium caseinate.

Quality indices of the set-yoghurt prepared from bovine milk treated with horseradish peroxidase

“…The data showed that the yoghurt prepared with the HRP and FA-treated milk had the largest hysteresis loop area while that prepared with the control milk had the smallest one (Table 3). It is known that the hysteresis loops is assumed to be the difference between the energies required for structural breakdown and rebuilding, and stronger thixotropy led to greater hysteresis loops (Damin et al 2009). In the present work, the yoghurt prepared with the HRP and FA-treated milk showed the largest thixotropy while that prepared with the control milk exhibited the smallest thixotropy.…”

Fortification of dahi (Indian yoghurt) with omega-3 fatty acids using microencapsulated flaxseed oil microcapsules

“…Similarly, Akalin et al (2012) studied textural characteristics of probiotic yogurts fortified with sodium calcium caseinate (SCaCN) and WPC; and reported that fortification with SCaCN increased the firmness more than WPC in probiotic yogurts during storage (P < 0.05). Damin et al (2009) also showed that yogurt made with milk supplemented with sodium caseinate resulted in significant increase in firmness. However, Jelen et al (1987) observed no significant difference in firmness of yoghurt gels made from milk with various casein to whey protein ratios.…”

Quality attributes of the set-style skimmed yoghurt containing enzymatic cross-linked or thermal polymerized whey protein isolate

“…The control yoghurt and yoghurt sample IX were considered to be the least and most stable, respectively, as the respective hysteresis loop areas of the control yoghurt, yoghurt samples III, and IX were 126.5, 201.6, and 267.5 (Table 2). Hysteresis loop is assigned to be the difference between the energies required for structural breakdown and rebuilding (Damin et al, 2009). Larger hysteresis loop areas of the yoghurt samples III and IX reflected that greater energy was required for their structural breakdown.…”

“…WPC and WPI both can be used in yoghurt production in order to enrich protein content. Whey protein addition has been observed to increase strength of yoghurt gels (Krzeminski, Grosshable, & Hinrichs, 2011;Lucey, Munro, & Singh, 1999), decrease syneresis (Kücükcetin, 2008), and enhance viscosity (Damin, Alcântara, Nunes, & Oliveira, 2009). It is known that thermal treatment of whey protein induces protein denaturation and more importantly polymerization of whey protein (Fitzsimons, Mulvihill, & Morris, 2008), which brings about modified properties to whey protein.…”