Chemistry

• Vegan


   a vegetarian who does not eat dairy products, eggs or any other products that are derived from animals.
• Factors why people may be vegan

  1. Personal: Some people believe it is wrong to kill and eat animals. Some simply do not like the taste of meat.
  2. Religion: Some religions do not permit their followers to eat meat (for example, Muslims are not allowed to eat pork).
  3. Health: Some people choose to become a vegetarian for health reasons because meat is high in saturated fat.
• Factors why people may be vegan

  1. Environment: Some people believe that meat production pollutes the environment more than crop production.
  2. Social: Some people are influenced by their friends and family.
  3. Economic: Meat is often more expensive than plant-based foods.
• How to get the right amount of protein?

  Vegans may need to consider soya or quinoa because they are two plant sources of protein
• How do they get the right amount of calcium?

   Vegans should ensure their calcium needs are achieved by including fortified foods such as white bread and breakfast cereals.
• Cheese making stages

  1. Acidification. A starter culture is added to milk that will change lactose into lactic acid. This changes the acidity level of the milk and begins the process of turning milk from a liquid into a solid.
  2. Coagulation. The process of transforming the liquid into a semisolid. When making cheese, an enzyme called rennet is added to the milk to solidify it
• Cheese making stages pt2

  1. Curds and whey. As the milk solidifies, it forms curd and whey. The curds are the solid part and whey is the liquid. In this step, the curds are cut using a knife
  2. Salting. Salt is added for flavour. It also acts as a preservative so the cheese does not spoil as it spends lots of time aging and it helps to form a natural rind on the cheese.
• Cheese making pt3

  1. Shaping. The cheese is out in a basket or a mole to form it to or a specific shape
  2. Ripening. Ages the cheese till it teaches optimal ripeness
• How is bacteria used in making cheese?

  -The bacteria ferment lactose produces lactic acid

  -The acid acts on the proteins to thickens it

  -Gives it a sour, tangy taste
• Eatwell guide

  Fruits and vegetables

  -1/3 rd of your daily food intake
• Eatwell guide

  Starchy carbohydrates

  -1/3 rd of your daily food intake

  -Choose high fibre, wholegrain options e.g.. potatoes
• Eatwell guide

  Dairy products

  -Some dairy but low fat options or alternatives e.g. soya
• Eatwell guide

  Protein

  -Two portions of fish a week

  -Or alternatives like pulses

  -Eat less processed meats like bacon
• Eatwell guide

  Oils and spreads

  -Use unsaturated oils and spreads e.g. olive oil
• Eatwell guide

  -6-8 glasses of fluid a day

  -Eat less sugary and fatty foods like muffins
• Sensory testing


  Humans taste by their tongues and nose
• Preference tests


  used to find out which food a person enjoys more
• Types of preference tests

  1. Paired preference test: person given two slightly different foods and they choose their favourite
  2. Hedonic rating test: people rate the food using a scale and are given a variety of foods
• Reasons why people waste food

  1. Spoiled
  2. Overcooked/ burnt
  3. Not covered
  4. Passed use-by date
• How produces/retailers waste food?

  1. Retailers reject food if it is damaged or spoiled
  2. Imperfect foods get rejected too
  3. Supermarkets stock more than they can sell to not disappoint customers
• How can we reduce waste?

  1. Plan meals and correct portion sizes
  2. Pay attention to use-by dates
  3. Use up contents of fridge before buying more food
  4. Eat left-overs
  5. Donate unwanted food to food banks
• How is food packaged?

  1. Plastic
  2. Paper
  3. Glass
  4. Metal
• Suitable packaging


  -Protects food from being damaged while in transport

  -Preserves food by stopping contamination
• How is packaging bad for the environment?

  1. Gets used once then ends up in a landfill site
  2. Litter is dangerous to animals
  3. Plastics take a long time to biodegrade
• How can we reduce environmental impact?

  1. Recycling e.g. tins and glass
  2. Buy products with little to no packaging
  3. Choose products with biodegradable packaging
• Gluten


  A protein found in wheat flours
• How gluten works?

  -Formed when water mixes with flour to make dough
• Formation function of gluten in bread


  -Molecules of gluten are coiled, means they can stretch and bend

  -Dough needs to be kneaded to work the gluten so it becomes longer and stronger
• Formation function of gluten in bread pt2

  -When it reaches a high temperature the gluten coagulates and the dough stays stretched
• Emulsification


  Keeps oil and water in a stable emulsion
• How are emulsions formed?

  When oily and watery liquids are shaken together
• Examples of emulsifications

  Milk and mayonnaise
• Process of emulsification

  1. The molecules have two different ends (hydrophobic and hydrophilic)
  2. The water molecules bond with the hydrophilic end and the oil molecules bond with the hydrophobic end
• Process of emulsification pt2

  1. The bonds hold the oil and water together in a stable emulsion