Diet and food production Flashcards
What can eating too many fats lead to?
Obesity (Cancer, Diabetes, arthritis)
Atherosclerosis
CVD (CHD, heart attacks, angina, stroke)
High cholesterol
What food increases the amount of HDL?
Unsaturated fats
What type of fat decrease the amount of HDL?
Low-fat diet
What type of fat Increases the amount of LDL?
Saturated fats
What type of fat decreases the amount of LDL?
Low-fat diet, polyunsaturated and monounsaturated
Why is selective breeding in animals used?
Increase the amount of food that each animal is able to produce (productivity). This is helped by giving the animals antibiotics.
Which microorganisms are known in food production?
Yeast
Penicillium
Lactobacillus
Examples of uses of microorganisms
Yoghurt and cheese are both formed when Lactobacillus bacteria acts upon milk.
Bread rises when yeast cells respire anaerobically to produce carbon dioxide.
Alcohol is produced following the fermentation of sugars found in cereal crops or fruit by yeast cells.
Negative effects of microorganisms
Food spoilage
Mould on foods
Foods becoming sweet as sugars are released (mush)
Food poisoning (E.coli)
Advantages of using microorganisms in food (8)
- Low in saturated fats and cholesterol
- Less likely to cause atherosclerosis
- Less land area than raising livestock
- Produced in any climate or in any season
- Fewer ethical and religious issues
- Tailored to meet demands
- Less risk of disease transfer
- Cheap to produce after factory has been set up.
Disadvantages of using microorganisms (7)
- Different texture and taste from meat
- Less iron than in animals
- People may be averse to eating fungi
- Growth conditions also favour the growth of disease-causign organisms.
- Expense of jobs in farming
- Isolated and purified from any toxic by products
- Higher set up costs
How can the use of fertilisers increase the product of food?
Replace minerals in the soil which may have been removed by the previous crops. They contain Nitrate, Phosphate and Potassium. They increase the rate of growth and the overall size of crops
How can pesticides increase the production of food?
Kill organisms that cause diseases in crops. These organisms would reduce yield or kill the crop. Many crops are sprayed with fungicides to reduce fungal growth in the leaves or roots. Sheep are dipped to kill ticks.
How can antibiotics increase the products of food?
Infected animals can be treated with antibiotics to reduce the spread amongst animals that are intensively farmed in close proximity to each other. Such diseases could reduce the growth performance of the animals and may impair reproduction.
What is salting?
Dehydrates any organisms as water leaves by osmosis.
What is adding sugar?
Dehydrated any organisms as water leaves them by osmosis.
What is pickling?
Acid pH denatures any microorganism’s proteins and enzymes.
What is heat treatment?
Kills harmful organisms by Pasteurisation or Ultra-heat treatment (UHT)
What is irradiation?
Kills organisms by disrupting their DNA structure. (X-rays and gamma radiation)
What is freezing?
Retards enzyme activity so their metabolism, growth and reproduction is slow.
