Composition, Solubility, and Stability of Whey Powders

Abstract

Eleven samples of acid and sweet whey powders from a wide geographical area were analyzed for general and amino acid composition. Acid whey powders from standard cottage cheese processes averaged 11.4% total protein. One acid whey powder from high heated cottage cheese milk and another from lactic acid casein manufacture contained only 8.8 and 9.3% total protein. The lysine in commercial acid whey proteins was slightly higher than in whole casein. Compositionally, acid and sweet whey powders differed in protein, lactic acid, mineral elements, and lecithin. Calcium and phosphorus in eight acid whey powders averaged 1.78 and 1.13% and in three sweet whey powders .62 and .77%. Acid whey powders had a higher zinc content, 41.7 ppm, than sweet whey powders, 9 ppm. Sodium and potassium and most phospholipids and vitamins (riboflavin, thiamine, and ascorbic acid) did not vary appreciably between acid and sweet whey powders, but lecithin was higher in sweet whey powders. Solubility of whey powders in water and in 5% ethanol in water ranged from 91.4 to 99.7% and in 5% sodium chlorine solutions, 72.8 to 98.2%. Acid whey powders generally were more stable to storage at room temperature than sweet whey powders. Microorganisms in acid whey powders were few. © 1973, American Dairy Science Association. All rights reserved.