359. A note on the effect of the temperature of pre-heating of spray-dried whole milk on the biological value of its proteins

Abstract

Previous work from this laboratory has indicated that the biological value of the proteins of milk is not affected by pasteurization (1), by evaporation and condensation (2) or by spray or roller-drying (3). Sterilization (4), on the other hand, caused a statistically significant decrease of 6% in the biological value; with this process heating at a high temperature is more prolonged than in the other forms of heat treatment.It was of interest to find out whether the difference of 30°F. in the pre-heating temperature of the spray-dried whole milks described by White, Smith & Lea (5) in the preceding paper would have any effect on the biological value of the proteins.

Effect of the drying process on the nutritive value of milk Part 2. Biological evaluation

“…As early as 1939 HENRY et al [7] reported no effect by either roller or spray drying. HENRY et al [9] reported similar results. COULTER et al [2] concluded that the biological value of spray dried milk is not inferior to that of the milk from which it was prepared, unless oxidative deterioration or sugar-protein interaction has occurred.…”