Dietary sources of whey protein
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Whey Protein Dietary Sources: Milk, Cheese, and Dairy By-Products
Whey protein is a major protein found in milk, making up about 20% of the total protein content, with the remaining 80% being casein. Whey is separated from casein during the cheese-making process, where it remains as the liquid by-product after milk curdling. This liquid, once considered a waste product, is now recognized as a valuable dietary protein source and is widely used in food and nutrition products 46.
Common Food Sources of Whey Protein
Milk and Dairy Products
Milk is the original source of whey protein. When consumed as a whole, milk provides both casein and whey proteins. Dairy products such as yogurt and some soft cheeses also contain whey protein, though in lower concentrations compared to milk itself 246.
Cheese Production By-Products
The most significant dietary source of whey protein is the liquid left over after cheese production. This liquid whey is processed to create various whey protein products, including whey protein concentrate, isolate, and hydrolysate, which are commonly found in protein supplements and functional foods 46.
Whey Protein-Enriched Foods
Whey protein is now added to a variety of foods to boost their protein content. Examples include flavored milk, protein-fortified pasta, ice cream, dessert puddings, muesli, and savory dips. These products are designed to make it easier for people to include whey protein in their diets and are generally well-accepted in taste trials .
Nutritional Value and Composition
Whey protein is considered a complete protein because it contains all nine essential amino acids required by the human body. It is also low in lactose, making it suitable for many people with lactose intolerance. In addition to protein, whey contains carbohydrates, fats, immunoglobulins, minerals, and other bioactive compounds that contribute to its health benefits 46.
Conclusion
Whey protein is primarily sourced from milk and is most abundantly available as a by-product of cheese manufacturing. It is now widely used in various food products and supplements due to its high nutritional value and health benefits. Including milk, cheese by-products, and whey-fortified foods in the diet are the main ways to obtain dietary whey protein 456.
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