Effect of incorporation of cottage cheese whey solids andBifidobacterium bifidumin freshly made yogurt

Abstract

SummaryFresh rennet-coagulated cottage cheese whey was vacuum concentrated to 400 g total solids kg−1, and part of this evaporated whey was acidified to pH 4·6 to prepare whey protein concentrate. Both products were used separately to replace non-fat dried milk in yogurt. Diacetyl concentration increased on fortification with whey protein concentrate, and acetaldehyde increased with evaporated whey. However, the use ofBifidobacterium bifidumas a supplementary starter culture in addition toStreptococcus thermophilusandLactobacillus delbrueckiisubsp.bulgaricusreduced the concentration of diacetyl and acetaldehyde. Incorporation of whey solids stimulated the growth ofStr.thermophilusandBifid. bifidumin yogurt but the count ofLb. bulgaricuswas reduced whenBifid. bifidumwas incorporated. Examination of the organoleptic properties of the yogurts showed that both forms of whey solids were satisfactory replacements for non-fat dried milk. Fortification by whey protein concentrate improved the textural properties. Supplementation byBifid. bifidumhad only a marginal effect on the flavour of the product.

The effects of inoculant variables on the physicochemical and organoleptic properties of Doogh

“…According to Table 3, treatments made by simultaneous employment of bifidobacteria and yoghurt bacteria during fermentation had significantly higher sensory acceptability than those fermented by yoghurt bacteria only. This is in contrary to the findings of Baig and Prasad (1996) that reported that B. Bifidum as a supplementary starter culture in yoghurt reduced the flavour score of yoghurt. Other study is consistent with previous results made by Davidson et al.…”

Physical characteristics of yoghurts made using exopolysaccharide-producing starter cultures and varying casein to whey protein ratios

“…The increase in available nutrients from WP may partly influence the growth of yoghurt bacteria, and hence shortening the fermentation time. Baig and Prasad (1996) and Dave and Shah (1998) reported that WP stimulated the growth of S. thermophilus.…”

“…Modler et al (1983) and Guzma´n-Gonza´lez, Morais, Ramos, and Amigo (1999) found that yoghurt supplemented with WPC had lower apparent viscosity and firmness than control yoghurt made without fortification. Baig and Prasad (1996) and Bhullar, Uddin, and Shah (2002) found that supplementation of milk with WPC improved the apparent viscosity and textural properties of the resultant yoghurt. These differences may be due to the variations in the composition of whey protein-based ingredients.…”

Cheddar whey processing and source: II. Effect on non‐fat ice cream and yoghurt1

“…Numerous researchers reported the use of whey and modified whey products in yoghurt (Jelen & Horbal, 1974; Hartman, 1975; Morris et al. , 1995; Baig & Prasad, 1996). The textural characteristics of yoghurt are largely dependent on its total solids content.…”