Final answer:
The other 60% of whey protein typically includes components like carbohydrates, fats, water, minerals, and possibly added flavors or sweeteners. Carbohydrates may include lactose, and minerals may consist of essential nutrients like calcium. High-quality whey protein isolate is lower in these non-protein components.
Step-by-step explanation:
If a whey protein contains 40% protein by weight, the other 60% consists of various other components. These components may include carbohydrates, fats, moisture (water content), minerals, and sometimes added flavors or sweeteners. Carbohydrates may come from sugars or lactose (if not filtered out as in whey isolate), and fats are usually present in small amounts, particularly in whey concentrate. The mineral content, often referred to as ash, can include essential minerals such as calcium and magnesium. Moisture is inevitable as whey protein is not completely dry. Some whey protein products may also contain additives such as emulsifiers, vitamins, or thickeners to enhance product stability, mixability, and nutritional value.
It is essential to read the nutrition label of a whey protein product to understand its complete composition fully. High-quality whey isolate will have less of the non-protein components, making it a more pure protein source, especially for individuals managing carbohydrate and fat intake.