Crude goat whey fermentation by <i>Kluyveromyces marxianus</i> and <i>Lactobacillus rhamnosus</i>: contribution to proteolysis and ACE inhibitory activity

Abstract

Unsupplemented acid goat whey containing 0.96% protein and 2.76% lactose was fermented aerobically with 32 microflora extracted from various raw milk cheeses and dairy products. These microflora were screened for their ability to hydrolyse whey proteins (alpha-lactalbumin and/or beta-lactoglobulin) and to generate peptides inhibitors of Angiotensin I Converting Enzyme. Five microflora were able to degrade whey protein. The most efficient microflora was able to fully hydrolyse alpha-lactalbumin and to a lesser extend beta-lactoglobulin. It was extracted from Bamalou des Pyrenées cheese. Micro-organisms involved consisted of yeast Kluyveromyces marxianus and lactobacillus Lactobacillus rhamnosus. Both were able to produce ACE inhibitory peptides after whey fermentation.