Food Preservation And Cooking Methods

Question 1

Drying

Answer 1

reduces water activity which prevents bacterial growth

E.g Meat,apples, apricots and grapes

Question 2

Freezing

Answer 2

keeping prepared food in cold storages.

Makes bacteria dormant

Question 3

Smoking

Answer 3

It cooks, flavours and preserves food exposing it to the smoke from burning wood.
Smoke is antimicrobial and antioxidant
Used on meats and fish
However it increases the risk of cancer

Question 4

Vacuum packing

Answer 4

It creates a vacuum by making bags and bottles airtight.
Since there is no oxygen in the created vacuum bacteria die.
used for dry fruit.

Question 5

Salting

Answer 5

Salting (curing) removes moisture from foods like meat

Salt kills and inhibits growth of microorganisms

Question 6

Sugar

Answer 6

used in syrup form to preserve fruits
Food can be cooked in sugar till it crystallises e.g candied peel and ginger.
Used for glazed fruit they get a coating of sugar syrup.
used with alcohol e.g fruit in brandy.

Question 7

Lye

Answer 7

Lye AKA Sodium hydroxide turns food alkaline and prevents bacterial growth.

Question 8

Canning and bottling

Answer 8

sealing cooked food in sterile bottles and cans.
The container is boiled to kill or weaken bacteria.
Once the container is opened the food is at risk of spoilage.

Question 9

Jellying

Answer 9

cooking in a material that solidifies to form a gel.
E.g Fruits and marmalade
the jellying agent is usually pectin it is naturally found in fruit.
Sugar is also added.

Question 10

Potting

Answer 10

Potting is a traditional British way of preserving meat by placing it in a pot and sealing it with a layer of fat.

Question 11

Jugging

Answer 11

Jugging is preserving meat by stewing it in an earthenware jug or casserole.
Brine or wine is used to stew meat in and sometimes the animal’s blood.

Question 12

Burial in the ground

Answer 12

there is lack of light, oxygen and desiccants in the soil
cool temperatures and good pH level,
E.g cabbages and root vegetables.

Question 13

Modified atmosphere

Answer 13

operates on the atmosphere around food
E.g Salad crops are packaged in sealed bags with an atmosphere modified to reduce the oxygen concentration and increase the carbon dioxide concentration.

Question 14

Using an organism

Answer 14

used on cheese, wine and beer because are preserved for a long time.
This method uses benign organisms
They introduce them to food and they make an environment which is not suitable for harmful pathogens to grow.

Question 15

High pressure food preservation

Answer 15

is a method that presses foods inside a vessel and experts a large amount of pressure
This disables microorganisms and prevents spoilage
food retains its appearance, texture and flavour.

Question 16

Modified atmosphere packaging

Answer 16

Modified Atmosphere Packaging extends the shelf life of fresh food products. The atmospheric air inside a package is substituted with a protective gas mix which ensures that the product will stay fresh for as long as possible.

Question 17

Pasteurisation

Answer 17

refers to the process of heating milk to at least to 63°C for 30 min or at least 71.5°C for 15 seconds then both are cooled immediately to a temperature of 10°C or less

Question 18

Pickling

Answer 18

Pickling means preserving food in brine (salt solution) or marinating in vinegar (acetic acid)
Different types: chemical pickling and fermentation pickling.
commercially sodium benzoate or EDTA is used