Greater Utilization of Whey Powder for Human Consumption and Nutrition

During 1966 the United States produced 2.7 billion pounds of cheese, including creamed Cottage, which led to about 23 billion pounds of fluid sweet and acid whey (4). I f all this whey had been dried, i t would have amounted to approximately 1.0 billion pounds of sweet whey powder from Cheddar, Swiss, and Blue cheese, and approximately 500 million pounds of acid whey powder from Cottage, Cream, and I tal ian cheese. Much of the fluid sweet whey, and practically all of the fluid acid whey, produced in this country is diverted to streams near the cheesemaking facility, or pumped into municipal sewer systems, and irretrievably lost from any further utilization by man. This is a t ragedy in a world becoming increasingly short of food, since cheese whey is a rich source of nutrients. Approximately 54% of the nutrients from milk are found in the fluid sweet whey of Cheddar cheese, while about 73% of the nutrients of the non-fat milk used for Cottage cheese show up in fluid acid whey. These organic nutrients, if unused, place costly burdens on sewerage systems. Fo r example, the biological oxygen demand (BOD, 5 day) of fluid whey is 32,000 ppm (3). At two neighboring upstate New York villages, a recent engineering survey indicated that $700,000, or about 35%, in capital outlay, and $22,000 in annual operating costs would be saved if a contemplated joint new municipal sewerage system was constructed without facilities for treating whey from a medium-sized Cottage cheese plant situated in one of the villages (5). As a food source for human consumption, fluid whey from Cottage cheese is less acceptable because of its h igh lactic acid content. Neutralization is possible; however, the process adds to the expense, changes the whey characteristics, and introduces more sodium ions. I t is now possible to produce at a few cents a pound and on a large industrial scale a highly dispersible, non-hygroscopic acid whey powder from Cottage cheese and related products. The powder contains approximately 2.5 per cent moisture, 12 per cent protein, 65 per cent lactose, 6 per cent lactic acid, and large quantities of calcium; in fact, all of the calcium that originally existed in the milk. Fur thermore, acid whey powder contains the vitamin B complex, vitanfin C, and the natural milk fermentation flavor compounds, like diacetyl. Acid whey powder has found a very limited use in the making of process cheese food, frui t sherbets, and bakery goods. The problem that remains is how to utilize the great bulk of fluid acid whey that is not used in these products, either as a liquid or a powder. Prel iminary research at Cornell has indicated that non-hygroscopic acid whey powder possesses an excellent potential as an inexpensive, natural acidulant for coagulating milk. In fact, there is some evidence that its use increases the effectiveness of certain processes. Results of these observations are reported here. The making of Ricotta cheese from whole milk generally involves commercial lactic s tarter and high heat as dual precipitat ing agents. Coagulation occurs at about 178 F when the cold milk is init ially acidified with lactic s tarter at a p H of 6.0. Other precipitants used, but infrequently, are vinegar and fluid sour whey. Fluid sour whey has been limited to the making of whey Ricotta, but for whole milk Ricotta, its use is unrealistic because of the disproportionately large quantities required and because of the excess dilution effect on the casein of milk. Furthermore, under the lat ter circumstances, it would be most difficult to obtain the desired soft, tender texture, and mild, walnutty flavor of ideal Ricotta. In the present study, whole milk Rieotta cheese was made with commercial non-hygroscopic acid whey powder as the coagulant, replacing lactic starter. Depending on the original acidity of the whole milk, 2.0 to 2.5 kg of unneutralized, commercial acid whey powder per 100 kg whole milk produced an optinmm p H 6.0. Manufacturing occurred in a 30-gal stainless steel kettle equipped with direct and jacketed steam heat in a manner generally employed by industry (1). The whole milk was obtained either from the Cornell University herd or from local I ta l ian cheese factories. Ricotta cheese produced by acid whey powder as the coagulant was excellent in texture and flavor. The weight of cheese from the pr imary precipitate, using acid whey powder, was 24.0 per cent greater than that obtained with commercial lactic starter from the same quantity of milk and at the same pH, Table 1. Two weeks later, in another experiment on whole milk from the I ta l ian cheese factory, not reported here, the weight of Ricotta cheese, with acid whey powder, was 20.2 per cent greater. No secondary precipitat ion was attempted in this experimental series, so total net yields are not available, but the above weight differences demonstrate a marked ef-