Food production

What are the 3 heat treatments of milk?

• Pasteurisation

• Sterilisation

• UHT

What is the temperature and time of Pasteurisation?

72C for 15 seconds

What is the temperature and time of Sterilisation?

130C for 30 minutes

What is the temperature and time of UHT?

135C for 1 sec

What is the effect on nutrition of Pasteurisation?

Little, small decrease in levels of vitamin B12,B2 and C

What is the effect on nutrition of Sterilisation?

Destroys some nutrients such as vitamin C and folic acid.

What is the effect on nutrition of UHT?

Little effect, may reduce some such as vitamin C

What is the effect on colour of Pasteurisation?

None

What is the effect on colour of Sterilisation?

Gives a more yellow colour

What is the effect on colour of UHT?

Gives a more brown colour

What is the effect on taste of Pasteurisation?

None

What is the effect on taste of Sterilisation?

Makes it taste sweeter

What is the effect on taste of UHT?

Makes it a little bit more rich

What is homogenisation?

The process in which milk is forced through small openings under high pressure, thus breaking up the fat globules.

What is the primary processing of milk?

• It starts on the farm with cows being milked 2-3 times a day

• milk is then transported from the farm to the factory to be processed

• the milk is then pasteurised

• the cream is then separated from the milk. It is added back depending on what type of milk is required

• the milk is then homogenised

what is fortification?

The process of adding micro nutrients to food that are most likely not normally there. Can be voluntary or by law.

what is enriched food?

one or more nutrients are added to them and are added to replace those lost in food processing.

What do cholesterol lowering products contain?

Natural extract from plants which stops cholesterol from being absorbed into the bloodstream

what is the function of a preservative?

• Make food last longer

• wider range of products

• improve flavour

what is the function of colouring?

• meet expectations

• promote benefits

what is the function of flavouring?

• improve flavour

• meet expectations

what is the function of an emulsifier?

Maintain texture

what is the function of a stabiliser?

Maintain consistency

What are the advantages of a preservative?

• extend shelf life

• reduce food waste

What are the advantages of colouring?

Improve appearance of foods

What are the advantages of flavouring?

Enhance, improve or strengthen flavour

What are the advantages of an emulsifier?

Mixes together ingredients which wouldn’t normally mix.

What are the advantages of a stabaliser?

Prevents separation of mixtures from emulsifiers.

What are the disadvantages of a preservative?

some can be linked to a higher risk for developing cancers

What are the disadvantages of colouring?

Linked to hyperactivity in children

What are the disadvantages of flavouring?

Can cause symptoms similar to an allergic reaction

What are the disadvantages of an emulsifier?

• Can cause liver disease

• some people report flatulence and bloating

What are the disadvantages of stabilisers?

• Damage to internal barrier

• some people experience flatulence and bloating

Describe the muscle tissue in meat.

It is made up of long thin fibres which are held together by connective tissue. These are either collagen, which holds bundles of fibres together or elastin, which binds the muscle together or the fibres to the bone.

what happens to collagen during slow, moist cooking methods?

it is converted to gelatin which is a soluble protein which is soft and tender and easier to eat and digest.

What is hanging?

a term used to describe the storage of meat after slaughter.

Should be hung at 1℃ for a minimum of 7 days.

how can meat be classified?

• poultry

• meat

• offal

how is meat processed?

• salting

• smoking

• chilling

• freezing

• canning

• marinade and rubs

• mechanical action

What nutrients are found in meat?

Protein.

Red meat contains Iron,Zinc and B vitamins.

Describe the muscle tissue in fish.

The muscle fibres are found in short blocks with no elastin and only a thin sheet of connective tissue surrounding them. This ensures it is relatively tender and only requires a short cooking time.

how can fish be classified?

• habitat

• fat content

  OR

• white fish

• oily fish

• shellfish

What nutrients are found in fish?

Vitamin D and B2 and Omega 3 and 6

how can fish be processed?

• salting

• smoking

• marinades or pickling

• freezing

• chilling

• canning

How can vegetables be classified?

• roots

• tubers

• bulbs

• stems

• leaves

• flower heads

• fungi

• fruit

• seeds and pods

what nutrients are in vegetables?

vegetables which grow above ground are a source of vitamin C

seeds and pods contain protein, dietary fibre and some vitamin C

vegetables that grow below ground contain carbohydrates and fewer vitamins

How can fruits be classified?

By their type:

• Citrus

• Tree

• Stone

• Berries and soft fruit

• Dried fruit

• Exotic

What can be done to slow down enzymatic browning?

• Controlling the temperature, atmosphere or moisture

• Coating with wax

• Blanching

• Drying

• Preserving in sugar

• Freezing

• Preserving in acid

• Canning

What is the classifications of cereals?

• Wheat

• Rye

• Rice

• Maize

• Barley

• Oats

What is the structure of cereals?

• Hair ( Beard )

• Bran

• endosperm

• crease

• scutellum

• germ

Why fortify foods?

• to increase nutrition content of foods

• to replace nutrients lost during processing

• to produce a product that is similar to another

• to increase the sale of the product

• improve quality

• to reduce nutrient deficiency of a country

What are the important parts of the wheat grain which are separated during milling?

The endosperm,bran and germ

what is the extraction rate of wholemeal flour?

100% (all of grain used)

what is the extraction rate of brown flour?

85% (some bran and germ and the endosperm)

what is the extraction rate of white flour?

72% (endosperm used)

what is white flour fortified with?

Calcium, Iron, Vitamin B1 and B3

what is the percentage of protein in self-raising flour?

10%

what is the percentage of protein in strong flour?

17%

what is a staple food?

A food that is eaten regularly and is often a main part of peoples diets

what is semolina?

a course-ground flour, which comes from wheat

define extraction rate

the percentage of flour by weight that is taken from the whole grain to make flour

what is durum wheat?

a yellowy, high-protein wheat that is grown especially for pasta-making.

what is the chorleywood bread process?

the name of the bread-making process in bakeries

what is the structure of semi-skimmed milk?

• 88% water

• 5% carbohydrate

• 3.5% protein

• 1.5% vitamins and minerals

• 1.7% fat

what is micro-filtered milk?

Milk which has gone through a super-fine filtration system which removes souring and spoilage bacteria.

This is then pasteurised and has a shelf life for up to 45 days.

How is milk turned into cheese?

1. Pasteurise the milk: Destroys bacteria, makes milk ready for starter culture. Milk is cooled

2. Add the starter culture: starter culture added to ‘ripen’ the milk. Lactic acid bacteria change lactose into lactic acid. Temp is 25-35C for 30 mins.

3. Add rennet: This helps the milk coagulate. Milk turns into curd and whey. Takes 30 mins

4. Cut curd and heat: curd is cut with cheese knives into small pieces. Different temps make different types of cheese. Soft cheeses are made from soft curds at lower temps.

5. Drain whey: Whey is drained and the curds form a mat

6. Texture curd: Curd mats are cut and piled on top of one another. Cheddaring removes more whey and allows the mats to ‘knit’ together in a tight structure.

7. Salt: salt is added to produce the right texture and flavour

8. Form into blocks: Salted curd is placed into cheese hoops and pressed into blocks

9. Store and age: cheese is stored in coolers until the desired age is reached

10. Package: cheese cut and placed into blocks. Wax, foil, paper, plastic and cloth can all be used to protect cheeses

How is milk turned into yogurt?

1. Pasteurise the milk: Pasteurised milk is homogenised so fat droplets are dispersed. Less bacteria so ready for starter culture

2. Warm the milk: Milk is warmed to 42C

3. Add the starter cultures: Lactic acid bacteria is used for starter culture. Ripening lets lactose to lactic acid

4. Hold: Milk is held at 42C. Fermentation creates a soft gel as protein sets

5. Cool: yogurt is cooled to 7C. fermentation stops

6. Add flavour: fruits and flavours are added

7. Package: pumped from fermentation vat to pots. Chilled to below 5C

How is fruit turned into jam?

1. Select fruit: under-ripe fruit has more natural pectin

2. Prepare fruit: wash and drain the fruit and remove any bruised fruit or seeds/stones/stalks

3. Add water and acid: simmer the jam. pectin is released from fruit with the help of the acid

4. Add sugar: stir gently to dissolve sugar completely

5. Add pectin: add liquid pectin, if the fruit is low in natural pectin

6. Boil: a full,rolling boil is required. Stir frequently

7. Test and pour into jars: setting point for jam is 105C. Use the wrinkle test to ensure this point has been reached. Pour into sterilised jars

what are the effects of canning on food?

Destroys some vitamin C and B groups as they are sensitive to heat.

what are the effects of drying on food?

destroys some vitamin C and B groups but makes vitamin A and E more concentrated in a product