Jam making (Jam is often called a preserve), is a traditional method of food preservation which uses
sugar to prevent the growth of micro-organisms and enable the jam to set into a gel.
Conditions required to enable gel to form in
jam:
Enough pectin
Enough acid
Enough sugar
Pectin is a polysaccharide and is found in
fruits. If the fruit is slightly under-ripe, it will
have more pectin than if it is over-ripe.
Fruit should be in good condition
Fruit should not be mouldy, soft or
damaged. How to make it:-
1. The fruit is stewed for a while with some
water to extract pectin.
2. Sugar is then added, stirred until dissolved.
3. Then the mixture is boiled quickly until the
jam reaches 105 C (setting point for jam)
When boiled with sugar, water and acid (from
fruit), pectin will form a 3D gel that sets as the jam
cools.
4. The hot jam is poured into clean, dry, hot,
sterile jars and sealed.
5. The jars are left to go cold, in which time
the gel will form and trap the fruit, sugar
and water.
Safety:-
The jars are heated in the oven to destroy micro-
organisms and to prevent glass from shattering
when hot jam is poured in.
The jams are sealed to prevent micro-organisms
getting into the jam.
sugar to prevent the growth of micro-organisms and enable the jam to set into a gel.
Conditions required to enable gel to form in
jam:
Enough pectin
Enough acid
Enough sugar
Pectin is a polysaccharide and is found in
fruits. If the fruit is slightly under-ripe, it will
have more pectin than if it is over-ripe.
Fruit should be in good condition
Fruit should not be mouldy, soft or
damaged. How to make it:-
1. The fruit is stewed for a while with some
water to extract pectin.
2. Sugar is then added, stirred until dissolved.
3. Then the mixture is boiled quickly until the
jam reaches 105 C (setting point for jam)
When boiled with sugar, water and acid (from
fruit), pectin will form a 3D gel that sets as the jam
cools.
4. The hot jam is poured into clean, dry, hot,
sterile jars and sealed.
5. The jars are left to go cold, in which time
the gel will form and trap the fruit, sugar
and water.
Safety:-
The jars are heated in the oven to destroy micro-
organisms and to prevent glass from shattering
when hot jam is poured in.
The jams are sealed to prevent micro-organisms
getting into the jam.
