PRESERVATION
The 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
Reason why this Examples
Preservation method
preserves food
Removing
moisture
Drying (sundrying, freezedrying or
spray-drying)
All microorganisms need
moisture to grow;
by removing the
moisture, growth is
retarded
Fruit, meat,
fish,
vegetables,
pasta
soups,
sauces, milk
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Smoking
Cold smoking – food Preserve
is salted in brine and partly by
then smoked slowly drying
Hot smoking – food
is cooked during
smoking
Chicken,
fish, meat,
cheese
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Treating with additives:
Salt
Makes water unavailable for microbial growth Meat, fish,
Bacteria can’t thrive in a salty environment
vegetables
Sugar
Makes water unavailable for microbial growth
Prevent microbial growth
Chemicals
Prevents the growth of yeasts and bacteria
Benzoic acid
Sodium benzoate
Salicylic acid
Prevents the growth of yeasts and bacteria
Dissolves easily in cold water. Prevents the
decay of organic substances
No unpleasant flavour food
Fruit (jam)
Pickled meat, pork,
jam, jelly, fish
Pickles, fruit juices,
acidic sauces
Fruits, vegetables
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Heat treatment
Pasteurisation
Inactivates
enzymes
Destroys microorganisms
Kills microorganisms
Prolongs shelf life
Sterilisation
Dairy products,
eggs
vegetables, fruit
and milk
Meat, poultry,
fruit juices and
milk
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Reducing
temperature
Refrigeration
Freezing
Slows down bacterial
growth on food
Reduces the growth
rate of bacteria due to
the low temperature –
bacteria is inactive
Water is unavailable to
bacteria because it has
turned into ice
Milk, fish,
meat, poultry,
fruit,
vegetables
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Excluding
oxygen
Canning
Heat used during
canning destroys
micro-organisms
Excluding air means
micro-organisms can’t
multiply
Fruit,
vegetables
meat, fish,
jam
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Drying
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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]
Ingredient list and
food additives
BRAND NAME
Nutritional Information
NAME OF PRODUCT
Directions for use
Storage
Instructions
Name & Address
Barcode
14/01/2013 14:30
Batch Number
Best before
BB 14/01/15
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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
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
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Activity
Evaluate the information on a can of soft
drink (or other) by completing the tick list in
your manual
Checklist-Label.docx
Brainstorm.
1 Preserves that you will make with your learners
2 How will you include these preserves in your
menus.
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