[Demonstration and identification of a new Maillard compound in heated milk].

By means of polarography a new Maillard product (5a) was detected in heated milk. The compound was isolated from a glycine/lactose mixture, which had been heated in buffer at pH 6,8, and then freeze dried by extraction with ethylacetate/methanol. According to its spectroscopic properties, 5a is 4-0-beta-D-galactopyranosyl-2-hydroxy-2-methyl-2H-pyran-3-(6H)-one. Though the amount of 5a formed during heat treatment of milk corresponds to the severity of heat stress, the usefulness of 5a as an indicator with respect to intensity of heat treatment is limited. 5a is rather rapidly converted to galactosyl isomaltol; also unknown peaks develop in the polarogram.