The application of membrane filtration technology in milk
concentrating equipment can reduce energy consumption, waste water pollution and by-products of comprehensive utilization, especially the recovery and utilization of whey, which can produce remarkable economic benefits.
Desalination and concentration of whey
Low molecular weight water, salt and lactose can be separated from whey by ultra-filtration (UF), which improves the ratio of protein, lactose and salt in concentrate. With the increase of concentration, the protein content in the product can be adjusted to the required value. Whey can be condensed to more than 25% of total solids. After spray drying, whey protein concentrate can be obtained, and its protein content can reach 35 to 80%.
Reverse osmosis (RO) was used to remove moisture from sweet whey and then evaporative drying. The salty whey produced by the production of cheese and other hard cheese (which has a high salt content) is difficult to treat as sweet whey. It must be desalinated before it can be recovered, evaporated and dried.
Because ultra-filtration (UF) can completely intercept protein in milk or whey, while lactose and ash can be completely permeated. Therefore, the process of "dilution ultrafiltration" can be used to concentrate protein while removing lactose and ash as much as possible. The high protein skimmed milk powder and whey powder of desalination and de-lactose were prepared for the production of ice cream, yoghurt, soft cheese and other fermented dairy products.