PRESERVATION The aim of food preservation is to preserve food for later use.

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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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