TRANSFORMATION OF EGG CHOLESTEROL DURING BACTERIAL FERMENTATION

Microbial fermentation of separated egg yolks was carried out at 25-de grees-C for up to 9 days using a Bacillus coagulans strain B1. Yolk sa mples were analyzed for cholesterol prior to and following fermentatio n. Little change in cholesterol was observed during the first 2 days o f fermentation although after 5 days and after 8 days it was reduced b y 32.9 and 49.6%, respectively. During the last 2 days of fermentation , the reduction in cholesterol levelled off at 49.6%. Examination of t he cholesterol products formed showed that 35% of cholesterol was oxid ized with 12% of products identified. Of those identified, the major o nes were 7beta-hydroxycholesterol (32.5%), cholesterol triol (19.2%), 7alpha-hydroxycholesterol (19.1%) and 25-hydroxycholesterol (7.2%).