Vacuum frying has been adopted for frying different foods, but mostly for fruits and vegetables.
There is need for some pre and after treatments which play role in moisture removal, product yield, final product moisture content, fat content of the product and fat distribution in the final product.
Blanching: This step is done to prevent enzymatic activity before vacuum frying by either steam blancher or hot water blancher.
Freezing: Contribute to form a porous sponge-like structure and improve the texture of the vacuum fried food by means of a quick freeze machine.
Vacuum Frying: Vacuum frying is achievable at lower temperature than conventional frying, therefore vacuum fried products have better nutritional quality, enhanced colour and oil degradation is much lesser than normal frying.
Defatting: Vacuum fried products, after frying are separated from excess oil by centrifugal defatting unit without breaking the vacuum.
Packaging: Similar to conventional fried products, the vacuum fried products are also having tendency of rancidity. PET or Aluminum film laminate by means of nitrogen gas filling packing machine may be used for packaging vacuum fried products.
