Food Production Flashcards
What is primary processing?
When foods are harvested to turn into a basic product which will then be used to help form products to be sold
E.g wheat harvested
What is secondary processing?
When primary processed foods are used to make quality products to sell in supermarkets
E.g wheat used to produce flour
Describe the process of wheat turning into flour
Wheat is grown in a field
The harvesting process removes the wheat grains from the plant
The harvested wheat grains are stored until they are needed for use
The harvested wheat is transported to a mill
The wheat is cleaned and conditioned (to soften the bran layer)
Flour is milled using a range of rollers and sieves
The bran, wheat germ and endosperm are separated and blended into different types of flour
Name parts of a wheat grain
Endosperm
Wheat germ
Bran layers
Describe the steps of processing milk
Cows are milked at least twice a day
Milk is stored at 4 degrees and transported for processing at a dairy
Milk is heated to a very high temperature for a short time to destroy pathogenic bacteria - this is called pasteurisation
Pasteurised milk is separated into cream and liquid components
Cream and liquid components are re blended
Homogenisation takes place - ensures milk has an even consistency - this involves milk being pushed through a hole at pressure, so that large fat modules are broken down and dispersed evenly
Name three examples of secondary food processing
Turning wheat flour into pasta
Turning milk into yogurt
Turning fresh fruit into jam
Describe the steps of processing milk into yogurt
Milk is homogenised, then pasteurised at a temperature between 85 degrees amid 95 degrees to destroy micro-organisms
Milk is then cooled to between 40 degrees and 43 degrees
A special non pathogenic bacteria culture is added
Mixture is incubated between 37 and 44 degrees for 4-6 hours
Bacteria in culture ferment the milk turning lactose into lactic acid which denatures and coagulates the milk proteins-makes yoghurt set
Yoghurt is cooled to 4.5 degrees to stop bacteria growing
Yoghurt can be pasteurised now
Flavourings can then be added
What is milling?
Breaking cereal grains down and separating the layers, turning the grain into flour
When turning wheat into flour, what does sieving the flour do?
Removes the outside layers and germs
Describe what happens during primary processing of animals straight after slaughter
Blood is drained away
Skin and hide (leather) are removed
Carcase split open lengthways and the internal organs are removed
Edible internal organs (offal) are also removed
Beef carcases are split in half completely due to large size
Pig, sheep and lamb carcases are often, but not always, kept whole
How does processing affect the sensory and nutritional properties of an animal?
Hanging the meat is important to develop its flavour and texture
This is because before slaughter, animals store the carbohydrate glycogen in their muscles
After slaughter glycogen is broken down to lactic acid - helps preserve meat
What affect does hanging meat produce?
Allows the natural enzymes in meat enough time to start to tenderise the protein and develop its particular flavour
To enable a gel to form in jam, what must there be enough?
Pectin
Acid
Sugar
What is pectin?
A polysaccharide
If a fruit is slightly under - ripe will it contain more or less pectin?
More
When boiled with sugar, water and acid, what will pectin form?
A three - dimensional gel that sets as the jam cools
Describe the steps in turning fruit into jam
Fruit, sugar, water and acid (from fruit) is boiled
Pectin will form a three-dimensional gel that sets as the jam cools
When jam is made, the fruit is firstly stewed for a while with water to extract pectin
Sugar is then added, stirred until dissolved
Mixture is boiled quickly until jam reaches 105 degrees (setting point of jam)
Hot jam is then poured into clean, hot, sterile jars and sea, to prevent microorganisms from getting into jam
Jam jars are left to cool - gel will form and trail fruit, sugar and water
Why are jam jars heated in the oven?
To destroy microorganisms and prevent glass from breaking when hot jam is poured in
Why is bacteria culture added to ferment the lactose sugar?
This will produce lactic acid
Lactic acid will denature and coagulate milk proteins - makes milk semi solid
What does cooling the milk stop?
The fermentation process
Describe the steps in the production of cheese
Milk is pasteurised - heated to 72 degrees for 15 seconds then cooled to 30 degrees
Special bacteria culture is added - turns lactose into lactic acid
Rennet is added (enzyme) - coagulates the protein
Curds are cut - solid curds are cut up finely using special knives
Draining of liquid whey
Drying curd - curd is stacked into slabs that turned over at regular intervals
Milling curd - slabs of curd are heated + put through curd mill and cut into small pieces
Salt is added and curds are pressed
Cheese is then placed on shelves for a few weeks or months in a special room
Why is milk pasteurised?
Pathogenic bacteria can grow and multiply in milk
Pasteurisation kills the pathogenic bacteria
Why does lactose sugar turn into lactic acid?
Lactic acid:
Coagulates protein in milk
Adds flavour and texture to cheese
Helps preserve cheese
What is the purpose of rennet?
Turns milk into a semi-solid called curds and a liquid called whey
Why are curds cut?
Helps release whey
Why is whey a valuable by product of the cheese making process?
Whey contains high biological value protein
Why is the curd stacked into slabs?
Stacking helps more whey drain off
Why is the curd cut?
Cutting curd into small pieces helps to form final texture of the cheese
Why is cheese pressed?
Pressing makes cheese become a solid block
Why are mature cheeses ripened for a long time?
So they develop strong flavours