Fast growth in a popular market
Products derived from milk and whey are of four main types:
- Protein-based ingredients – used in infant formula, food and sport nutrition products
- Mineral-based ingredients – used as nutritional supplements
- Lactose-based ingredients – used in snack, confectionary and nutritional products
- Hydrolysates – used in infant formula and dietary products
Across these products, we at Tetra Pak provide innovative membrane filtration solutions that help you create the high-quality and high-value products the market demands.
Uses
Whey protein concentrate and isolate
High dry-matter content
Whey protein concentrates (WPC) are high-value products that are widely used in food processing and are produced using membrane filtration.
WPC powder is created by drying the retentates from ultrafiltration of whey. Its protein content ranges from 35 percent to over 80 percent. WPC powder exceeding 80 percent protein is produced by ultrafiltration of liquid whey followed by diafiltration to remove lactose and ash. Diafiltration involves adding water to the feed to wash out lactose and minerals. These then pass through the filtration membranes.
Whey protein isolate (WPI) containing more than 92 percent protein, measured as dry matter, is a popular ingredient in protein supplements. It is produced by microfiltration of whey that has been pre-concentrated by ultrafiltration.
Milk protein concentrate and isolate
Functional properties
Milk protein concentrate (MPC) and milk protein isolate (MPI) are concentrated forms of milk protein that are commonly in sports nutritional, functional food and infant nutritional products.
They contribute functional properties to food products, such as emulsification, water binding and texture enhancement.
MPC is made by treating milk with ultrafiltration. The membranes allow water, lactose and minerals to pass through while retaining proteins. Further concentration removes additional water to create a concentrated milk protein product.
MPI typically has a higher protein concentration than MPC and is also produced using microfiltration to isolate specific protein fractions and remove impurities.
Micellar casein concentrate and isolate
Food and supplement ingredients
Micellar casein concentrate (MCC) and micellar casein isolate (MCI) are protein products derived from milk. They are made specifically from casein, the main protein in milk. They are widely used in the food and supplement industry.
The production of MCC involves separating casein from whey by microfiltration. The process helps retain the micellar structure of casein – a natural arrangement of spherical clusters called micelles.
MCI has a higher and more concentrated casein protein content than MCC and requires more filtration and purification steps to isolate and concentrate the micellar casein fraction while minimizing other protein presence.
Mineral and lactose products
Diversification opportunity
Mineral-based ingredients such as calcium phosphate are commonly used as nutritional supplements, while lactose-based ingredients such as lactose and permeate powder have wide applications in snack, confectionary and nutritional products. Protein and lactose hydrolysates are popular ingredients in infant formula and dietary products.
All derived from milk and whey and produced using microfiltration or ultrafiltration, these products represent an opportunity for dairy and food producers interested in expanding their portfolios and market reach.
Technologies
Fat and protein separation
Ultrafiltration
Ultrafiltration is used for concentrating large molecules such as fat and protein in raw or pasteurized whole or skim milk and for reducing lactose and mineral content.
Typical products include milk protein concentrate (MPC) and milk protein isolate (MPI). These are produced using polymeric spiral membranes. Diafiltration is often used here to increase the protein-to-dry-matter ratio to achieve high-grade varieties such as MPC 85.
Ultrafiltration is also used to concentrate whole or standardized milk for the production of fully or partially concentrated cheeses.
Ultrafiltration membrane pores are larger than in nanofiltration and the pressure applied is relatively low. Salts, sugars, organic acids and smaller peptides pass through as permeate. Proteins, fats and polysaccharides remain as retentate.
Ion and mineral removal
Nanofiltration
The diluted streams from microfiltration and ultrafiltration processes are often concentrated using nanofiltration or reverse osmosis – or a combination of the two. The nanofiltration process removes or recovers water and also separates monovalent ions, thus demineralizing the product.
Nanofiltration plays a role in the production of products such as milk protein concentrate (MPC), milk protein isolate (MPI) and infant formula.
The technology uses slightly more open membrane pores than reverse osmosis. These allow small ions such as dissolved minerals to pass but exclude larger ions and most organic components such as bacteria, spores, fats, proteins, gums and sugars.
Valuable concentration step
Reverse osmosis
Reverse osmosis is a highly useful and cost-effective way to pre-concentrate milk and whey powder mixes before drying.
It is a powerful driver of energy efficiency in powder evaporation and drying because pre-concentrating the product generates valuable energy before the drying process.
Reverse osmosis can also be used to concentrate milk, whey and solids as well as for further concentration of the permeate from ultrafiltration.
