Post on 17-Jan-2016
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PRESERVATIONThe aim of food preservation is to preserve food for later use
USES AND ADVANTAGES OF PRESERVED FOOD
• prevents the food from being spoiled by enzymes, micro-organisms.
• increases the safe storage period of foodstuffs.• it increases availability of food out of season.• transportation of the food is easier. foods are
easy to store, e.g. canned/dried fruit does not require refrigeration or freezing.
• it can save time and labour. Peeling, slicing• labels offer nutritional information.
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Method of Preservation
Reason why this method preserves food
Examples
Removing moistureDrying (sun-drying, freeze-drying or spray-drying)
All micro-organisms need moisture to grow; by removing the moisture, growth is retarded
Fruit, meat, fish, vegetables, pastasoups, sauces, milk
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SmokingCold smoking – food is salted in brine and then smoked slowlyHot smoking – food is cooked during smoking
Preserve partly by drying
Chicken, fish, meat, cheese
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Treating
Salt
Sugar
ChemicalsBenzoic acidSodium benzoate
Salicylic acid
with additives:
Makes water unavailable for microbial growth Bacteria can’t thrive in a salty environment
Makes water unavailable for microbial growth
Prevent microbial growthPrevents the growth of yeasts and bacteria
Prevents the growth of yeasts and bacteria
Dissolves easily in cold water. Prevents the decay of organic substancesNo unpleasant flavour food
Meat, fish, vegetables
Fruit (jam)
Pickled meat, pork, jam, jelly, fish
Pickles, fruit juices, acidic saucesFruits, vegetables
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Heat treatmentPasteurisation
Sterilisation
Inactivates enzymes Destroys micro-organismsKills micro-organisms Prolongs shelf life
Dairy products, eggsvegetables, fruit and milk
Meat, poultry, fruit juices and milk
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Reducing temperatureRefrigerationFreezing
Slows down bacterial growth on foodReduces the growth rate of bacteria due to the low temperature – bacteria is inactiveWater is unavailable to bacteria because it has turned into ice
Milk, fish, meat, poultry, fruit, vegetables
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Excluding oxygenCanning Heat used during
canning destroys micro-organismsExcluding air means micro-organisms can’t multiply
Fruit, vegetables meat, fish, jam
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Drying
FOOD PRESERVATION AT HOME
1. Chutney and sauces / pickles 2. Jam 3. Fruit and vegetables (bottled)
• Open pot method [used for hard fruit e.g. Peaches]• Water bath method
[used for very soft fruit e.g. Grapes]
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BRAND NAME
NAME OF PRODUCT
14/01/2013 14:30 Batch Number
Name & Address
Ingredient list and food additives
BB 14/01/15Best before
Directions for use
Nutritional Information
Barcode
Labels must include the following information (not all applicable on home made preserves)• The brand name• The name of the food product • Lot identification/batch or serial number• Name and address of supplier• Mandatory warning statements• Ingredient list • Processing method
Labels on Homemade Preserved food
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Preparation of peaches before preservation
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Sterilisation of bottels for preservation
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Strawberry Jam
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Testing jam
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Bottling jam
Activity Evaluate the information on a can of soft drink (or other) by completing the tick list in your manualChecklist-Label.docx
Brainstorm.1 Preserves that you will make with your learners2 How will you include these preserves in your menus.
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