Experiments dealing with the isomeric forms of lactic acid produced by Lactobacilu8 acidophilus and Lactobacillus bulgaricus have failed to take into account the possibility that R and S dissociants might play a determining r6le. The results reported show wide discrepancies varying from active to racemic lactic acid, including mixtures of both (

What is the most desirable temperature at which to store acidophilus milk? The answer to this question depends upon one's point of view and is conditioned by a variety of conflicting considerations. It is generally agreed that acidophilus therapy depends in the last analysis upon the ingestion of a large number of viable L. acidophilus. In the treatment of chronic constipation or diarrhea we have recommenled a daily dosage of one quart of acidophilus milk containing 200 billion viable organisms (Kopeloff, 1926). Whether or not such a requirement can be fulfilled when dealing with acidophilus milk on a commercial scale is a problem to be solved by the manufacturer. He must take into consideration: the palatability of his product, the contaminants therein and the time elapsing before use. Examination of commercial products has revealed a failure to meet specifications in many instances and only emphasizes the difficulties inherent in the problem (Kopeloff, Cohen, and Beerman, 1928). In a previous report on some temperature studies of acidophilus milk it was shown that after three days' storage in the icebox 90 per cent of the L. acidophilus organisms had been killed