engleski

The growth of ABT-5 culture in whey supplemented with whey protein concentrate

According to the literature, whey proteins can stimulate growth of certain lactic acid bacteria and bifidobacteria. This is very important for the application of probiotic cultures in dairy technology, because they grow slowly in milk and substrates based on milk. Relatively cheap and easily available source of whey proteins is commercial whey protein concentrate (WPC). Thus, in this research the influence of different amounts of WPC addition on fermentation of sweet reconstituted whey with mixed ABT-5 culture (Lactobacillus acidophilus, Bifidobacterium spp. and Streptococcus thermophilus) was examined. Whey fermentation at 37º C with and without 1.5% and 3% of WPC addition, has been observed and it was conducted until pH value 4.6 was reached. During fermentation titratable acidity, pH-values and the viable cells counts were observed. Fermentation lasted approximately 6.5 hours regardless the amount of WPC addition. Whey supplemented with WPC had a little higher titratable acidity during fermentation compared to whey without WPC. The viable cells count of Lactobacillus acidophilus was higher in whey supplemented with WPC (log CFU mL-1 = 7.13) compared to the whey without WPC (log CFU mL-1 = 6.63). The highest viable cells counts of Bifidobacterium spp. was observed in whey supplemented with 3% of WPC (log CFU mL-1 = 8.16) compared to whey without WPC (log CFU mL-1 = 6.84). The addition of WPC did not influence on the growth of Streptococcus thermophilus. The viable cells counts of Streptococcus thermophilus at the end of whey fermentation in all samples was nearly the same (approximately log CFU mL-1 = 9.29).

Lactobacillus acidophilus; Bifidobacterium spp.; Streptococcus thermophilus; whey protein concentrate; whey

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