Transformation of the Intestinal Flora through the Feeding of Unfermented Acidophilus Milk

Abstract

A description is given of an acidophilus milk containing a high concentration of viable L. acidophilus and yet similar in taste and physical properties to fresh milk, and having only a negligible quantity of free lactic acid. The product is virtually a sweet whole milk in which viable cells of L. acidophilus have been suspended in large numbers (in excess of 100 million per cc.). Growth of the organisms is held in check by keeping the milk cold. Since L. acidophilus has a growth temp. limit at about 20[degree] C, development of acid over a period of 2-3 days is prevented if the milk is held below 10[degree]. Data are presented to show that these organisms suspended in unfermented milk are capable of being implanted in the intestinal tract of white rats and of man. Exps. in which a number of individuals drank daily a quart of unfermented acidophilus milk were made to test out the effectiveness of such feeding in bringing about transformation of the intestinal flora. In the 16 exps. on human subjects, successful implantation of L. acidophilus, as determined by the plate method, was obtained in each case. In 12 of the 16 exps. a predominant L. acidophilus flora was obtained by regular consumption of approximately 1 quart of unfermented acidophilus milk per day, no other modification of the ordinary diets of the subjects having been made.