The production of dairy products, such as cheese or yogurt, leaves whey as a by-product. However, it is a “residue” with excellent nutritional properties which is used in full. It makes up almost 90% of milk and retains many of its nutrients: minerals, vitamins, sugars such as lactose and, above all, soluble proteins.
There are many products available on the market made from whey. Whey is one of the today’s main sources of protein and one of the most nutritionally valuable. Presentation as powder is one of the most widely used. Advertising of nutritional supplements with high whey content for children and the elderly or for athletes flood our daily life.
Industrial processing of whey powder
There are many new industrial processes that allow the separation and utilization of all whey components, one of the final products being whey powder.
How to get to whey powder: initial processes
The first processes to which the whey is subjected are very important, as its richness in nutrients makes it an ideal medium for the rapid development of bacteria. Buffering, clarifying and refrigeration are some of the initial processes applied to whey.
Concentration of total solids is the step prior to drying that will ultimately produce whey powder. The different concentration processes take from 6% to about 65% of total solids. Then, at this percentage, the whey concentrate can be subjected to drum drying or spray drying to finally obtain whey powder.
The whey powder thus obtained reach almost 90% of protein concentration and has functional characteristics of solubility, emulsification, foaming and gelling ready to be used as a highly nutritious supplement.
Sieving whey products
For its further use, the whey powder must have both a high bulk density and consistency in particle size. This is where the process of sieving through high quality industrial sieves comes into play. The efficiency of these sieves lies in their ability to separate the particles and in the absence of residue accumulation on the screens.
The most modern screening processes include equipment that incorporates vibration, as well as much finer screens, without compromising process efficiency. The very small size of the powder grains obtained can cause them to adhere to the screen mesh, reducing process efficiency.
Ultrasonic vibration motion: the ultimate in whey powder screening
The incorporation of a vibratory motion “decollates” the screen, allowing it to remain clean throughout the process. The vibration is produced by ultrasound, at a frequency that breaks the surface tension of the screen, obtaining a product free of contaminants.
This vibration frequency and increasingly finer meshes allow the separation of particles down to 20 microns. Thus, the products obtained are of increasingly higher quality in terms of the presence of unwanted particles.
The whey products markets
The market of supplement protein powders will continue to experience a gradual increase over the next few years. Only in the United States, sales are expected to reach $6.57 billion in sport nutrition, reaching all the whey protein market $12.4 billion by 2021. Globally, the market for whey products is forecasted to reach the $15.4 billion by 2024.
Another market increasingly demanding this protein supplement is the vegetarian market, which is growing in acceptance among younger groups of people. Although vegetarians do not consume products or by-products of slaughter, begin to accept the need to incorporate protein supplements into their diet.
Clearly, the growth of the market for whey products, specifically whey powder as a nutritional supplement, has forced the food processing equipment manufacturing industry to develop improvements and new technologies. Increasingly specific processes and more precise sieving devices have appeared on the market, but the last word has not yet been said.