Thiamin Content of Milk in Relation to Vitamin B1 Requirement of Infants

Abstract

The thiamin of milk is the only natural source available to the young infant. Thiamin assays on milk are difficult; in biol. assays by the curative technic, the depleted rats may not consume the quantity of test dose necessary; in the growth technic the basal diets must be completely adequate except in thiamin, and milk doses introduce added calories which may affect growth. In thiochrome assays thiamin may be lost if proteins are precipitated, and the absorption and elution of the vit. from the decalso column may not be quantitative. In this study all of these methods were employed as well as the fermentation technic. From the results on pasteurized milk, boiled milk formulae, evaporated milk, and breast milk, it appears that breast milk cannot furnish 200 [mu]g. of thiamin daily. The nursing infants studied usually have blood cocarboxylase levels of 3-4 [mu]g., compar-ing well with those receiving milk formulae; infants receiving manually expressed breast milk showed lower levels. Possibly the thiamin content of the breast milk was reduced during the 2-4 days of storage before it could be fed. The avg. pH of the breast milk samples was 8.1. in contrast to values of 6.8 for pasteurized milk and 6.2 for evaporated milk.