Food Applications

On a worldwide basis, the dairy industry is probably the largest user of membrane technology in food processing. RO is used as a preconcentration step prior to evaporation, NF is used for desalting cheese whey, ED is used for desalting milk and whey, and UF is used for purifying whey proteins from cheese whey to produce whey protein concentrates. UF is also used in the manufacture of cheese by preconcentrating the protein and fat to a level close to that normally found in the finished cheese. This precheese is then converted to cheese by conventional cheesemaking methods with appropriate modifications. The advantages of the UF method are that higher yields are obtained (1030% in some cases) due to retention of whey proteins in the final cheese; the amount of enzyme required may be lower; and volume of milk to handle in the cheese vats is reduced and less whey is produced (although the milk permeate still needs to be disposed of). The UF method has been especially useful with soft cheeses.

MF is used for defatting and clarifying whey prior to ultrafiltration. MF is also used to reduce the microbial load of milk to extend the shelf life of pasteurized milk and the quality of cheeses.

The second-biggest use of membrane technology is for fruit juices, where UF and MF have been used in the manufacture of clear juices such as apple, pear, pineapple, kiwi, grape, lemon, lime, and cranberry. The goal is to replace the conventional holding, filtration, and decanting steps and perhaps the final pasteurization step. This has resulted in higher yields; improved juice quality due to removal of pectins, polyphenol oxidase, and tannin-protein complexes; elimination of filter-aid and fining agents; and much lower processing costs. Concentration of fruit juices by reverse osmosis to high levels (>42 Brix) using a combination of high-rejection and low-rejection RO membranes has been commercialized but is not widespread.

Other food applications include production of vegetable protein concentrates and isolates (eg, from soybeans), concentration of eggs prior to dehydration, processing of animal products such as blood and gelatin, refining of sugars and syrups, removal of yeast from beer and wine, and de-gumming vegetable oils. It is increasingly being used in waste treatment and recovery and reuse of chemicals such as acid and alkaline cleaners that are used for cleaning food equipment.

Homemade Pet Food Secrets

Homemade Pet Food Secrets

It is a well known fact that homemade food is always a healthier option for pets when compared to the market packed food. The increasing hazards to the health of the pets have made pet owners stick to containment of commercial pet food. The basic fundamentals of health for human beings are applicable for pets also.

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