Whey powder is a valuable addition to the functional properties of various foods as well as a source of valuable nutrients because it contains approximately 50 percent of the nutrients in the original milk.

Composition

Whey powder consists primarily of carbohydrate (lactose), protein (several different whey proteins, mainly lactalbumins and globulins), various minerals and vitamins.

Typical composition for Whey Powder

Different Types of Whey Powder

• Sweet whey powder: is produced by drying fresh whey from which the milkfat has been removed during the preparation of Cheddar, Mozzarella, Swiss or other cheeses manufactured principally with rennet type enzymes (casein-coagulating enzyme preparations). It contains all the constituents, except water, in the same relative proportion as in liquid whey. Its pH in a 10 percent solution should be greater than 5.6. This type of whey powder represents the majority of the Canadian production.

• Acid whey powder: is produced by drying fresh whey obtained from Cottage, Ricotta or other fresh cheeses manufactured principally by acid coagulation (the pH of the milk is lowered by microbial fermentation process in which some of the lactose is converted to lactic acid). It is similar to sweet whey powder in composition except for its lower lactose content and its higher titratable acidity which makes its flavour slightly acidic compared to normal whey flavour found in sweet whey powder. Its pH in a 10 percent solution should be lower than 5.1.

• Demineralized whey powder: is produced from whey by selective removal of most (70-90 percent) of the minerals.

• Delactosed whey powder:  is produced from whey by crystallizing a majority of the lactose out and recovering the primary substance.

Whey powders shall contain less than 5 mg/kg of copper, 1 mg/kg of lead and 20 mg/kg of iron. They should be exempt of Salmonella, Listeria, coagulase-negative Staphylococcus and show a maximum Standard Plate Count of 50,000 colony-forming units/gram (CFU/g).

Various Uses

As a food additive, whey powder acts as binder and extender for many food products, such as beef preparations, chili con carne, poultry, sausage, soups and stews. Usage level is limited to 3.5 percent for sausage and 8 percent for chili con carne, pork or beef with BBQ sauce. It is widely used in bakery products, dry mixes, process cheese foods and spreads, frozen desserts, sauces, meat emulsions, salad dressings, confections, gravies, snack foods and beverages.

Demineralized whey powder as well as delactosed whey powder are used in infant foods, diet foods formulations, prepared dry mixes and for food products in which mineral profile and concentration are critical attributes.

Functional Properties

Nutritional and functional characteristics of whey proteins are related to the structure and biological functions of these proteins. Native whey proteins (globulins and lactalbumins), as 11 percent of constituents of whey powders, possess good functional properties related to solubility, foaming, emulsion formation and gelling. The high content of lactose plays an important role in flavour, aroma and browning reactions.

For more information on concentrated and dried dairy products, please visit the University of Guelph’s Dairy Science and Technology Web site.