Changes during heating water as the heat transfer

3 Changes during heating water as the heat transfer 

Water Boiling, pasteurisation, sterilisation, blanching, evaporation, extrusion cooking 

Storage In air, in vacuum, in inert gas, refrigerated, frozen storage, transport 

Another important food processing technology is pasteurisation. It consists of rapid heating to temperatures between 60 and 65°C in order to destroy microorganisms. Oxidoreductases are inactivated at the same time. As the heating is short, the destruction of antioxidants is only moderate. Losses of ascorbic acid are a good indicator of the destructive changes. Losses of ascorbic acid and carotenes are minimised by deaeration. 

Commercial sterilisation is a more severe process than pasteurisation as the temperature is higher (70-90°C). The process is used to protect food during long-term storage. The oxygen residue should be minimised before heating to reduce deterioration of antioxidants or, in some cases, antioxidants 

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