Recent Advances in Improving Dry Whole Milk. A Review

Abstract

The importance of having' a dry whole milk which reconstitutes to give a beverage closely approximating the characteristics of a fresh natural product has been recognized for many years by researchers, manufacturers, and users. This is part icular ly true during times of national and global emergencies, when the availability of fluid milk becomes greatly curtailed due to inadequate and often impossible distribution. The Quatermaster Corps of the U.S. Army, being faced with this situation during World W a r I I and again in the Korean War, established a program of research with various universities, during the early and middle 1950's, to investigate means of improving dry whole milk. The results of this program (4) have been of great assistance in clarifying many of the factors concerned with the low acceptabili ty of whole milk powder. The intent of this paper is to briefly review stone of the progress made during the past 15 y r in improving the over-all quality of whole milk powder. Improvements have resulted in flavor quality from an increased knowledge of the effects of fat, lactose-protein compIexing, and processing procedures on this characteristic; in dispersibili ty through better understanding of the physical factors involved; and in processing techniques which have made i t possible to eliminate or control factors responsible for poor quality in the past. Whole milk powder has been criticized in many respects. Firs t , i t has been very difficult to disperse even by mechanical means, and practically impossible without the use of warm water. Secondly, the flavor of the freshest powder has been inclined to be highly cooked and eggy, with butterscotch or cooked fat overtones and, finally, deterioration during storage has resulted in flavors characterized as oxidized, tallowy, rancid, stale, burnt feathers, powder flavor, fruity, coconut, malty, cereal, and a host of other descriptions. The widest use of dry whole milk in this country has been as an ingredient in the formulation of other foods or for infant feeding. In other areas throughout the world where fluid milk is not generally available, i t has received wide use as a beverage for all people. In this last respect, it is of interest that in such areas fluid milk is hardly accepted as milk, the standard being whole milk powder.