Direct-Acid-Set Cottage Cheese Whey as a Base for a Shelf-Stable Athletic-Type Drink ¹

A shelf-stable athletic-type beverage was developed from direct-acid-set cottage cheese whey. First, the pH of the whey was adjusted to 5.2 with a saturated potassium hydroxide solution. The whey was heated with stirring to 90°C and held for 10 min to coagulate the protein, which then was removed by filtering or centrifuging. Calcium hydroxide was added to increase the pH to 5.6, and then potassium hydroxide was added to bring the pH up further to 6.5. The whey was filtered or centrifuged again to remove the cloudiness caused by addition of calcium hydroxide and additional protein precipitation. Beta-galactosidase was added and whey was held at 5°C for 18 h to hydrolyze the lactose. Then, one part water was mixed with two parts whey before saturated citric acid was added to make an acceptable orange-flavored beverage. The beverage then was heated to 88°C and stored in 8-fl. oz. bottles capped with Teflon-lined closures. The levels of electrolytes, such as sodium and potassium, in this product were similar to those in commercially available athletic-type drinks. In two separate trials, involving 28 persons each, the whey-based drink, when compared with a commercial product, was preferred 64% and 46% of the time, respectively. During storage some of the added sucrose was hydrolyzed into glucose and fructose; however, a taste panel did not detect a change in sweetness in the stored products. The heat process used (88°C for 5 min) appeared to be adequate for commercial sterility. The stability of the product during storage was good and estimated to be longer than 6 months. Ingredient cost of the whey-based athletic-type drink was $0.14 per 32 fl. oz.