The Colon-Aerogenes Group of Milk

Abstract

Definite information concerning the significance of the colonaerogenes group of bacteria in milk is rather obscure. The characteristic gas fermentation and acid production class such organisms as undesirable in the manufacture of dairy products. Their influence, however, upon the quality of market milk is less definite. According to Harding (5), the three essential elements determining the quality of milk are--food value, healthfulness, and cleanliness. The colon-aerogenes group can effect the food value of milk only indirectly, in that through their undesirable fermentation they lessen the palatability of the commodity as a food. That the colon bacilli influence the healthfulness of milk is generally accepted, although very little direct proof is available. Such intestinal diseases as infantile diarrhoea, summer complaint and cholera infantum, commonly attributed to mill( in warm weather, have long been associated with this group. More recent investigations along this line, however, tend to make one hesitate in placing so much emphasis upon such organisms as formerly. Until more authentic data is available to the contrary, it is no doubt wise that such organisms should be considered as a suspicious source of the non-specific intestinal disorders due to milk. The colon family has long been considered of sanitary importance in milk. Numerous boards of health have adopted standards, based upon the colon content, for grading market milk. The usual assumption being that large numbers of colon indicate production under filthy conditions. Recent work, however, by Ayers, Cook and Clammer (2), indicate that large numbers of colon bacilli in milk represent growth due to holding at high temperature and not to initial contamination. The purpose of this investigation was to study the relation of the colon-aerogenes group to cleanliness of milk production.