Whey is a collective term referring to the serum or watery part of milk that remains after coagulation, which occurs primarily in the production of cheese and cottage cheese. The composition of whey varies considerably, depending on the milk source and the manufacturing process involved. But in general, whey is rich in lactose (milk sugar), minerals, vitamins, and “whey proteins.”
Grade “A” dry whey must be produced with Grade “A” whey in a Grade “A” plant. All other parameters for Grade “A” products are the same as “Extra Grade.”
Natural, functional, and high in nutrition, whey is the ingredient of choice for product developers. Whey ingredients have applications in baked goods, beverages, confections, dairy foods, meat products, salad dressings, nutraceuticals, sauces, and soups—with new uses continuously being identified.
How to Choose Between a Milk or Whey Ingredient
Milk and whey ingredients provide multiple benefits to food products. These benefits are often described as flavor, function, and nutrition. They provide a mild, dairy flavor that blends well with many food products. Their composition can consist of multiple components such as, proteins (caseins and/or whey proteins), milkfat, lactose, and ash (minerals), and thus provides many different functional properties described in the table below. These components also provide many of the same unique nutritional properties found in milk.
Milk and whey ingredients are used in a wide variety of food products including dairy products, baked products, confections, soups, sauces, infant formula, processed meats, prepared foods, and beverages. Selecting the right dairy ingredient for your application can be confusing because many milk and whey ingredients have a similar composition, for example nonfat dry milk (NDM) and whey protein concentrate 34 (WPC34). Even though the protein content is about the same, NDM consists of roughly 80% casein and 20% whey protein, while WPC34 is all whey protein. Often the choice is made based on price, but comparing the differences in functionality is probably the most important method of selection.
Solubility in water is the single most important functional property for a milk or whey ingredient. No matter which ingredient you choose, it must be soluble for it to be functional. The solubility of a milk or whey ingredient that contains protein is impacted by the pH of the food. Milk protein ingredients have good solubility above pH 6.0. Whey protein ingredients have good solubility at pH 3-7. Lactose, the main component in the ingredients lactose and milk/whey permeate (dairy products solids) has good solubility below a concentration of 14% in room temperature water, but has lower solubility (will crystallize) at refrigeration temperatures. The solubility of dairy ingredients that are high in calcium (such as milk/whey permeate), decrease with heat treatment and at a pH greater than 5. These are the primary characteristics to help select the right dairy ingredient for your application.
Functional Benefits of Milk & Whey Ingredients
|Solubility||Protein||Provides better performance in all applications|
|Browning||Protein and Lactose||Provides color and flavor development|
|Emulsification||Protein-caseins provide stronger emulsification than whey proteins||Provides binding and separation of fat globules and texture stability|
|Heat Stability||Protein-caseins are more heat stable than whey proteins||Prevents protein aggregation and settling for properly hydrated ingredients during high heat processing|
|Gelling & Heat Setting||Protein-whey proteins will denature and form gels with heat treatment||Provides structure and water holding properties|
|Water Binding & Viscosity Building||Protein-caseins have more water binding ability than whey proteins||Improves texture and mouthfeel; Helps to retain moisture and improve shelf life|
|Whipping & Foaming||Protein-whey proteins generally foam more than caseins||Provides aerated structure and texture|