Презентация к теме Healthy Food
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oxidation.ppt | 1.58 МБ |
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Presentation Why does food go Bad? OXIDATIONСлайд 2
Exposure to oxygen in the air affects food. Oxidation reactions happen when chemicals in the food are exposed to oxygen in the air.
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This is because of a reaction between the natural proteins called enzymes in the fruit and the oxygen in the air.
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Oxidation of food is a destructive process, causing loss of nutritional value and changes in chemical composition. Oxidation of fats and oils leads to rancidity and, in fruits such as apples, it can result in the formation of compounds which discolor the fruit .
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Antioxidants are added to food to slow the rate of oxidation and, if used properly, they can extend the shelf life of the food in which they have been used.
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We can reduce this effect and stop such as fruit and vegetables from turning brown by adding a natural acid.
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Moreover, we can put them in boiling water for ten seconds to destroy the enzymes or by preserving them in a sugary solution such as syrup.
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Air-tight packaging, using inert gases like nitrogen, vacuum packing and refrigeration can all be used to delay the oxidation process.
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