Whey | Overview
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.
Whey Products Standards Introduction
The whey processing industry initiated the development of standards for condensed and dry whey and whey products immediately after the founding of the Whey Products Institute in 1971.
U.S. Standards for Dry Whey that include both sweet- and acid-types now exist as a result of cooperative efforts between industry and government. Uniformity of product quality is ensured through grade specifications that are universally accepted and understood. This section includes these specifications for EXTRA GRADE and STANDARD GRADE dry whey.
ADPI task forces have developed industry standards for a number of additional dry ingredient products derived from whey. Through such standards, whey processors, and users/purchasers, have a clear understanding of product quality and the basis upon which such has been determined. Questions relating to a product’s quality thus may be eliminated by having standardized analytical test methods available to both buyer and seller and by referring these test results to specific grade standards.
Methods of analyses needed to accurately determine product composition, measure quality, and ascertain compliance with grade standards, have been reviewed and approved by an Institute Committee of technical experts, and are compiled in this publication.
In addition, several whey products have received GRAS affirmation and GRAS Notification and are listed in the appendices of this section.
The American Dairy Products Institute (ADPI), formed when the Whey Products Institute and the American Dry Milk Institute merged in April, 1986, is the national trade association of the processed dairy products industry, specifically representing the evaporated milk, condensed and dry milk and whey/whey products segments of the industry. As new whey products and improved analytical methods for the testing of all whey products continue to be developed, this publication will be updated to assist in maintaining uniformity within the industry.
Additional resources including the Dried Dairy Ingredients Handbook and more are available for ADPI members. Click the button to log-in to access these resources.
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
|Provides better performance in all applications
|Protein and Lactose
|Provides color and flavor development
|Protein-caseins provide stronger emulsification than whey proteins
|Provides binding and separation of fat globules and texture 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