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?
Pasteurise the milk: Destroys bacteria, makes milk ready for starter culture. Milk is cooled
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.
Add rennet: This helps the milk coagulate. Milk turns into curd and whey. Takes 30 mins
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.
Drain whey: Whey is drained and the curds form a mat
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.
Salt: salt is added to produce the right texture and flavour
Form into blocks: Salted curd is placed into cheese hoops and pressed into blocks
Store and age: cheese is stored in coolers until the desired age is reached
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?
Pasteurise the milk: Pasteurised milk is homogenised so fat droplets are dispersed. Less bacteria so ready for starter culture
Warm the milk: Milk is warmed to 42C
Add the starter cultures: Lactic acid bacteria is used for starter culture. Ripening lets lactose to lactic acid
Hold: Milk is held at 42C. Fermentation creates a soft gel as protein sets
Cool: yogurt is cooled to 7C. fermentation stops
Add flavour: fruits and flavours are added
Package: pumped from fermentation vat to pots. Chilled to below 5C
How is fruit turned into jam?
Select fruit: under-ripe fruit has more natural pectin
Prepare fruit: wash and drain the fruit and remove any bruised fruit or seeds/stones/stalks
Add water and acid: simmer the jam. pectin is released from fruit with the help of the acid
Add sugar: stir gently to dissolve sugar completely
Add pectin: add liquid pectin, if the fruit is low in natural pectin
Boil: a full,rolling boil is required. Stir frequently
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