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Published byNorman Rudolph Lee Modified over 8 years ago
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WALT Know reasons for food spoilage. Know benefits of preserving food. Know some methods of preserving food.
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What causes spoilage of food?
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Three main groups of microbes that cause spoilage : Bacteria Moulds Yeasts Source :http://resources.schoolscience.co.uk/SGM/sgmspoil1.html
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Bacteria – on raw meat, raw fish, raw milk, Yeasts and acid/salt tolerant bacteria -on cured meat Yeasts and moulds -On butter, yoghurt, cheese, fruits, vegetables Moulds - On cereals, nuts,
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Preservation of food ? Any ideas???
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Which methods do you know?
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Preservation of food Heating – pasteurisation, sterilising Cooling – refrigeration, freezing Chemicals – curing, pickling, fermentation, Sulphur dioxide, benzoic acid, ascorbic acid, propionic acid Drying Freeze drying Packaging Irradiation
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Questions 1.Why does food go bad? 2.Which methods do you know? 3.Why do we use preservation methods?
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Ham contains more vitamin C than a piece of fruit Vitamin C is also named ascorbic acid 137 milligrams 4 grams
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Food preservation experiment Food gets mouldy after a while. That shows us that …
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Mould, a problem for humans
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