Use of cheese whey for vitamin B12 production. 3. Growth studies and dry-weight activity.

The patterns of growth and vitamin formation by Propionibacterium shermanii in whey were similar to the patterns established in other substrates. The vitamin formation was observed during the latter part of the fermentation after the organism approached maximal growth. Lactose utilization by the organism corresponded to the logarithmic-growth phase of the organism. Analyses of the dried culture showed a large increase of vitamin B(12) in the fermentation solids compared with unfermented dried whey. A feed analysis showed a notable increase of protein and a large decrease in nitrogen-free extract of the dried fermentation solid compared with dried whey.