4th Form Exam Revision Flashcards
How does chilling help preserve food?
Slowing down the growth of bacteria
What is modified atmospheric packaging?
When you modify the air that surrounds the food in its packaging to help extend shelf life
How does freezing help preserve food?
Stops the growth of bacteria as ice crystals form around the food and protect it
What are the three types of freezing and how do they work?
Plate freezing - food is frozen between two plates
Blast freezing - freezing air is blasted over irregular shaped foods
Immersion freezing - food is immersed in or spayed with liquid nitrogen
What are the three types of drying and how do they work?
Sun drying - dries out food before spoilage happens
Spray drying - foods are spray dried to remove all of the water
Accelerated freeze drying - food is dried under a vacuum at reduced pressure
How does heat preservation work?
High temperatures stop bacterial growth by killing the bacteria
What are four chemicals for preservation?
Salt - preserves meat and fish by absorbing the water
Spices - preserves cooked meats
Sugar - stops bacterial growth, used in jams
Vinegar - acidic and used in pickles and chutney
How does smoking preserve food?
The smoke destroys the bacteria
What are the nutritional needs of pre-school children?
Calcium and vitamin d - bones and teeth formation
Protein - growth and repair which is important for growing and active children
Carbohydrates - good source of energy for active and busy children throughout the day
Fibre - needed for digestion
Vitamins - seeing in the dark, skin and hair
What are the nutritional needs for teenagers?
Omega 3 - brain function and brain development
Iron and vitamins c - teenage girls who are menstruating to replenish iron
Protein - growth and repair, teenagers growing during puberty
Boys need more calories than girls in general
Lots of carbohydrates as they are very active
What are the nutritional needs for later adulthood?
Limit alcohol due to the sugar content
Less saturated fast as they are at a higher risk of CHD and obesity
An adult with a more active lifestyle need more carbohydrates for energy
Nutritional needs differ if the person is pregnant/breastfeeding
What are the six functions of eggs
Aeration
Emulsification
Coagulation
Enrobing (coating)
Binding
Glazing
What is aeration used in?
Meringues
What is emulsification used in?
Mayonnaise
What is coagulation used in?
Sponge cake
What is enrobing used in?
Chicken nuggets
What is binding used in?
Meatballs
What is glazing used in?
Pastry
What temperature do eggs coagulate at?
70*C
How does emulsification work?
The lecithin in the yolk of eggs stabilises and thickens the mixture
What are the three key macronutrients?
Fats
Proteins
Carbohydrates
What are the two types of protein?
Low biological value
High biological value
What is an example of a low biological value food?
Lentils
What is an example of a high biological value food?
Beef or fish
What are proteins made up of?
Amino acids
How many essential and non-essential amino acids are there?
8 essential
12 non-essential
What are complementary proteins?
Two LBV proteins that come together to make a HBV protein
Carbohydrates are the … agents of food?
Bulking agents
What are the three groups of carbohydrates?
Monosaccharides
Disaccharides
Polysaccharides
What ae carbohydrates spilt into?
Sugars
Starches
What is the function of fats in the body?
Insulation
Protecting vital organs
Store for energy
What are the two types of fats?
Saturated fats
Unsaturated fats
What are the risks with saturated fats?
High in cholesterol so can lead to heart disease and obesity
What is an example of a saturated fat?
Butter
What is an example of an unsaturated fat?
Avacados
What are the two main micronutrients?
Vitamins
Minerals
What is the scientific name for vitamin C?
Absorbic acid
What is the scientific name for vitamin A?
Retinol
What is the scientific name for vitamin D?
Calsiferol
What is the scientific name for vitamin b1?
Thiamine
What is the scientific name for vitamin b2?
Riboflavin
What is the scientific name for vitamin b3?
Niacin
What is the scientific name for vitamin b12?
Cobalamin
Where are the b vitamins found?
Leafy green vegetables
Where is vitamin c found?
Citrus fruits
Where is vitamin a found?
Carrots
Where is vitamin d found?
Sunlight and fortified cereals
What is the deficiency disease associated with lack of vitamin c ?
Scurvy
What is the deficiency disease associated with lack of vitamin a ?
Night blindness
What is the deficiency disease associated with lack of vitamin d ?
Rickets
What is vitamin c needed for ?
To help your immune system
To absorb iron
What is vitamin a needed for ?
Needed for good eyesight and good skin
What is vitamin d needed for ?
Needed for strong bones and teeth
To absorb calcium
What are the tow most important minerals?
Iron
Calcium
What is calcium needed for?
For strong bones and teeth
Where is calcium found?
Milk
What is needed for calcium to be absorbed?
Vitamin d
What is iron used for?
Making red blood cells
What does iron need to be absorbed?
Vitamin c
Where is iron found?
Red meat
What does iron help prevent?
Anemia
When is extra iron necessary?
When woman are menstruating
What is emulsification?
The process of mixing two liquids that don’t naturally mix (like oil and water) into a stable mixture called an emulsion
What does sifting the flour do in bread making?
Introduces air which acts as a raising agent and helps the bread rise in the oven
What does adding warm liquid do in bread making?
Hydrates the flour
And at 37*C it allows the yeast to ferment and produce CO2
Sugars are released in fermentation which the yeast consumes - creates alcohol and CO2
What does mixing and nearing the dough do in bread making?
Two of the proteins in the flour become hydrated and gluten is formed
What does proving the dough do in bread making?
Some of the starch in flour is broken down and fermented by the yeast
CO2 is produced which causes the gluten to expand and makes the dough rise
What does knocking back do in bread making?
Removes large bubbles of CO2 which ensures an even texture and a better rise
What does baking do in bread making?
The dough rises as the CO2 expands
Yeast activity increases at first then the yeast is killed by the heat
The water is absorbed by the starch which swell and gelatinise
The gluten network trap the CO2
The gluten strands are stretched which helps form the finished bread structure
CO2 and alcohol are released
Dextrin is formed on the outside of the bread which gives it colour
How much should fruits and vegetables make up daily food intake?
1/3
How much should carbohydrates make up daily food intake?
1/3
How many portions of fish should you aim to eat in a week?
2 portions
What are good alternatives of proteins if your a vegetarian?
Beans
Pulses
Hwo many glasses of fluids are you supposed to consume in a day?
6-8 glasses
What are the four types of raising agents?
Mechanical
Biological
Chemical
Steam
What is an example of a chemical raising agent and where is it used?
Bicarbonate of soda - chocolate cake
What is an example of a biological raising agent and where is it used?
Yeast - bread
How does steam work as a raising agent?
When you use a very hot oven to cook a mixture that deliberately contains a lot of liquid (batters, Choux pastry) the water leaves the mixture as steam and as the steam rises it raises the mixture up.
What are five examples of mechanical methods of raising agents?
Folding
Beating
Whisking
Sieving
Creaming
What are 6 ways you can reduce food waste?
Plan meals and correct portion sizes and only buy the necessary ingredients
Correctly store foods and pay attention to used by dates
Use up the contents of your fridge before buying more food
Use leftover meals the day after or freeze them
Use the whole food
Donate unwanted foods to food banks
What are three reasons for wasting foods?
Too much food was cooked
It has passed its use by date
Food was prepared incorrectly
What is the raising agent used in Choux pastry?
Steam
What are examples of Choux pastry?
Profiteroles
Eclairs
Choux buns
Gougeres
