Serological differentiation of cow's, buffalo's, goat's and sheep's milks

Abstract

SummaryMilks of the closely related species ox, buffalo, goat and sheep were differentiated by the precipitin test using antisera to blood serum proteins. The antisera were made specific for the homologous species by absorption. The component of milk tested was the lactalbumin–lactoglobulin fraction present in whey. Fraudulent sale of diluted buffalo's milk, cow's milk–buffalo's milk–water mixtures and reconstituted whole and skim-milk powders as genuine cow's milk was detected. Of 270 milks serologically tested, 233 were cow, 26 buffalo, 1 goat, 3 cow–buffalo mixtures, 2 reconstituted whole-milk powders and 5 reconstituted skim-milk powders. Of the samples serologically identified as cow, 135 had analytical figures for fat and solid-not-fat (SNF) only just outside or within the buffalo range.Milk from any one species was detected in a concentration of 5% (v/v) in milk of a related species. Species identification was made of human milk stains in 2 medicolegal cases. Fresh cow's milk, reconstituted whole-milk powder and reconstituted skim-milk powder were differentiated.