Use of cheese whey for vitamin B12 production. II. Cobalt, precursor, and aeration levels.

Within the limits of this study, it was found that 5 ppm of cobalt was adequate to give good levels of vitamin B(12). The vitamin B(12) precursor 5,6-dimethylbenzimidazole was found to be adequate at 10 ppm in the absence of aeration. In the presence of aeration, a zero level of precursor was found to be most desirable. The analysis of variance showed aeration to be highly significant, and the aeration and precursor interaction to be significant. No other significant effects were observed.