Growth performance of whey protein hydrolysates in the media on different strains of probiotic bacteria

摘要

As whey protein being a precursor of bioactive substances this study was conducted to evaluate the influence of Whey Protein Isolate (WPI) and its peptic ortryptic hydrolysates on the growth of probiotics. The probiotic bacteria used in this study included selected strains of bifidobacteria (B. longum, B. bifidum, B. breve, B. infantis) and Lactobacillus acidophilus. The influence of the supplementation of WPI or its enzymatic hydrolysates on the growth of selected strains during 30 hours of incubation was studied in vitro by measuring the absorbance at 600 nm. Different concentrations of pepsin and trypsin (0.2 and 0.5% (w/w)) were used for hydrolysis of WPI. The growth stimulation of bifidobacteria was demonstrated to be higher with the peptic hydrolysates of WPI in comparison to WPI or its tryptic hydrolysates, whereas both the WPI and its peptic or tryptic hydrolysates stimulated the growth of L acidophilus compared to the control. This study provides evidence that the functional peptides released from major proteins of hydrolysed WPI, i.e. the peptides of ct-lactalbumin or ss-lactoglobulin stimulated the growth of probiotics, depending on the respective strain.