Source: https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-2-fats-and-oils [Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [GCSE](https://senecalearning.com/en-gb/revision-notes/gcse.md) › [Food Preparation](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation.md) › [AQA](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa.md) › Fats & Oils # Fats & Oils Food Preparation & Nutrition: AQA GCSE, topic 3.2.2 ## Changing Properties - Fats and Oils We can use fats and oils for different effects when we're cooking. ### Aeration ![Aeration](https://image-v2.cdn.app.senecalearning.com/2018-05/e7ee190d-98b0-4c7d-82ba-290c6b18bb32/shutterstock_447550504.jpg) - Aeration involves getting air into something. - We trap air in mixtures when we beat fats with sugar (known as creaming). - The added air lightens the mixture and gives it a fluffy texture. - Aeration causes cakes to turn out spongy and light when they're cooked. - We can use different methods to aerate foods, including beating or whisking. ### Shortening ![Shortening](https://image-v2.cdn.app.senecalearning.com/2018-05/7696988a-8653-4a68-b04f-a53ac213f2a4/shutterstock_227316352.jpg) - Flour particles gain a waterproof layer when they're covered in fat. We can cover particles in fat by rubbing fat into flour. - We might choose to do this if we want to form baked goods with firm textures (i.e. cakes, biscuits or shortbread). This is because the coating stops long gluten molecules from forming when we add water to flour. The dough doesn't develop an elastic (stretchy) texture. - We use shortening to form pies and tarts because we want the base to be solid and not rise. - Shortening fats don't contain any water - they are made of fat only. This prevents gluten from forming. ### Plasticity ![Plasticity](https://image-v2.cdn.app.senecalearning.com/2018-08/1b8961fc-34ca-4d03-baac-1197fc3cccbf/birthday-cake-380178_1920.jpg) - If something has plasticity, it can be spread and moulded. - We can spread and mould fats because they are made up of different triglycerides that each have different melting points. This means fats don't melt at a set temperature but soften gradually across different temperatures. - Fats with more plasticity are easier to spread. - Fats with more unsaturated fatty acids have more plasticity than those with less and are easier to spread. - Plasticity is useful in everyday cooking. For example: - Spreading peanut butter, aioli or butter on toast. - Making cream cheese and smoked salmon sandwiches. - Icing cupcakes with buttercream. ### 'Easy to spread' !['Easy to spread'](https://image-v2.cdn.app.senecalearning.com/2018-05/25f35eb2-579f-4d20-b826-ba5aa17dda2c/shutterstock_741921037.jpg) - You'll see some vegetable fat spreads labelled as 'easy to spread'. - These spreads are made up of triglycerides that melt at low temperatures (e.g. room temperature) so they're spreadable once they're out of the fridge. ## Changing Properties - Fats and Oils We can use fats and oils for different effects when we're cooking. ### Emulisification ![Emulisification](https://image-v2.cdn.app.senecalearning.com/2018-05/9884704e-672c-4bcd-9b3b-ca73f11d739c/shutterstock_258084893.jpg) - When we shake watery and oily liquids together, we create emulsions. Droplets from one of the liquids disperse throughout the other liquid. - We either create oil-in-water emulsions, like milk and vinaigrette, or water-in-oil emulsions, like butter and margarine. - We need to keep stirring or shaking the oily water so that the emulsions don't separate - they do this because oil and water don't naturally mix together. We can also use an emulsifier. ### Emulsifier ![Emulsifier](https://image-v2.cdn.app.senecalearning.com/2018-05/fd7cf725-d4d4-45da-b92f-b2a6ea02983c/shutterstock_663914143.jpg) - Emulsifiers are dual-ended molecules. They have a: - Hydrophilic end (water-loving) - bonds with water molecules. - Hydrophobic end (water-hating) - bonds with oil molecules. - The emulsifier keeps the water and oil together in what's called a stable emulsion. This means they don't separate. ### Lecithin ![Lecithin](https://image-v2.cdn.app.senecalearning.com/2018-05/3ad7c396-432c-45a2-891a-e21e4327464a/shutterstock_1086266372.jpg) - Lecithin is a natural emulsifier found in egg yolks and soya. - It's commonly used in foods, like mayonnaise, which is made up of oil, vinegar and egg yolk in a stable emulsion. ### Sauces and salad dressings ![Sauces and salad dressings](https://image-v2.cdn.app.senecalearning.com/2018-05/2f74af54-2120-4c76-bb29-3d6c56919030/shutterstock_272856290.jpg) - Mayonnaise and hollandaise sauce are examples of emulsion sauces. - Vinaigrette is an example of an emulsion salad dressing. - You must add liquid and emulsifier _before_ you add oil or fat when you're creating an oil-in-water emulsion. You must add the fat or oil very slowly and stir continuously as you add. ### Recipe for hollandaise sauce ![Recipe for hollandaise sauce](https://image-v2.cdn.app.senecalearning.com/2018-05/70589e72-d31d-468c-93ce-705a6d78cad9/shutterstock_618209174.jpg) - Place butter in a pan and melt. - Place lemon juice and egg yolks into a mixing bowl and stir. - Place the mixing bowl over simmering water to heat the mixture gently. - Slowly pour the melted butter into the mixing bowl, whisking continuously. - Whisk until the mixture is smoothly mixed. ## Test yourself on Fats & Oils - Which of the following is true of fat plasticity? - What is the name of the process of beating fats with sugar? - This emulsion is smooth, glossy, pale yellow, thick, and creamy. Which emulsion is this? - Mayonnaise is an example of what type of emulsion? [Practise this topic for free](https://app.senecalearning.com/classroom/course/d59d0e60-4fa8-11e8-bbba-738ab127bed6/section/2e3a92b0-5862-11e8-9078-fb33f179496c/session) - Previous topic: [3.2.1 Proteins & Carbohydrates](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-1-proteins-and-carbohydrates.md) - Next topic: [3.2.3 Raising Agents](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-3-raising-agents.md) ## Food Preparation & Nutrition: AQA GCSE contents ### 1 Food Preparation Skills - 1.1 Food Preparation Skills - [1.1.1 General Practical Skills](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-1-general-practical-skills.md) - [1.1.2 Knife Skills](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-2-knife-skills.md) - [1.1.3 Preparing Fruit, Vegetables & Using Equipment](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-3-preparing-fruit-vegetables-and-using-equipment.md) - [1.1.4 Cooking Methods: Prepare, Shape & Combine](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-4-cooking-methods-prepare-shape-and-combine.md) - [1.1.5 Sauce Making, Tenderising & Marinating](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-5-sauce-making-tenderising-and-marinating.md) - [1.1.6 Dough & Pastry](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-6-dough-and-pastry.md) - [1.1.7 Shaping & Finishing Dough](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-7-shaping-and-finishing-dough.md) - [1.1.8 Raising Agents & Mixtures](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-8-raising-agents-and-mixtures.md) - [1.1.9 End of Topic Test - Food Preparation Skills 1](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/1-1-9-end-of-topic-test-food-preparation-skills-1.md) ### 2 Food, Nutrition & Health - 2.1 Macronutrients - [2.1.1 Proteins](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-1-1-proteins.md) - [2.1.2 Proteins 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-1-2-proteins-2.md) - [2.1.3 Fats](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-1-3-fats.md) - [2.1.4 Carbohydrates](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-1-4-carbohydrates.md) - [2.1.5 Carbohydrates 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-1-5-carbohydrates-2.md) - 2.2 Micronutrients - [2.2.1 Fat-Soluble Vitamins](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-2-1-fat-soluble-vitamins.md) - [2.2.2 Water-Soluble Vitamins](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-2-2-water-soluble-vitamins.md) - [2.2.3 Minerals & Water](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-2-3-minerals-and-water.md) - [2.2.4 Minerals & Water 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-2-4-minerals-and-water-2.md) - [2.2.5 End of Topic Test - Macro & Micronutrients](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-2-5-end-of-topic-test-macro-and-micronutrients.md) - 2.3 Nutritional Needs & Health - [2.3.1 Informed Choices for a Balanced Diet](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-1-informed-choices-for-a-balanced-diet.md) - [2.3.2 Informed Choices for a Balanced Diet 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-2-informed-choices-for-a-balanced-diet-2.md) - [2.3.3 Energy Needs](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-3-energy-needs.md) - [2.3.4 Nutritional Analysis](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-4-nutritional-analysis.md) - [2.3.5 Diet Modifications](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-5-diet-modifications.md) - [2.3.6 Diet-Related Problems](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-6-diet-related-problems.md) - [2.3.7 Diet-Related Problems 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-7-diet-related-problems-2.md) - [2.3.8 End of Topic Test - Nutritional Needs & Health](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/2-3-8-end-of-topic-test-nutritional-needs-and-health.md) ### 3 Food Science - 3.1 Cooking of Food & Heat Transfer - [3.1.1 Reasons for Cooking & Heat Transfer](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-1-1-reasons-for-cooking-and-heat-transfer.md) - [3.1.2 Water-Based Cooking Methods](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-1-2-water-based-cooking-methods.md) - [3.1.3 Fat-Based Cooking Methods](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-1-3-fat-based-cooking-methods.md) - [3.1.4 Dry Cooking Methods](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-1-4-dry-cooking-methods.md) - [3.1.5 Dry Cooking Methods 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-1-5-dry-cooking-methods-2.md) - 3.2 Functional & Chemical Properties of Food - [3.2.1 Proteins & Carbohydrates](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-1-proteins-and-carbohydrates.md) - [3.2.2 Fats & Oils](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-2-fats-and-oils.md) - [3.2.3 Raising Agents](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-3-raising-agents.md) - [3.2.4 End of Topic Test - Food Science](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/3-2-4-end-of-topic-test-food-science.md) ### 4 Food Safety - 4.1 Food Spoilage & Contamination - [4.1.1 Microorganisms & Signs of Food Spoilage](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-1-1-microorganisms-and-signs-of-food-spoilage.md) - [4.1.2 Enzymes & Signs of Food Spoilage](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-1-2-enzymes-and-signs-of-food-spoilage.md) - [4.1.3 Food Poisoning](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-1-3-food-poisoning.md) - [4.1.4 Bacterial Contamination](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-1-4-bacterial-contamination.md) - [4.1.5 Microorganisms in Food Production](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-1-5-microorganisms-in-food-production.md) - 4.2 Principles of Food Safety - [4.2.1 Temperature Control](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-2-1-temperature-control.md) - [4.2.2 Ambient Foods & Food Labels](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-2-2-ambient-foods-and-food-labels.md) - [4.2.3 Preparing, Cooking & Serving Food](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-2-3-preparing-cooking-and-serving-food.md) - [4.2.4 End of Topic Test - Food Safety](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/4-2-4-end-of-topic-test-food-safety.md) ### 5 Food Choice - 5.1 Factors Affecting Food Choice - [5.1.1 Factors Which Influence Food Choice](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-1-factors-which-influence-food-choice.md) - [5.1.2 Food Choices](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-2-food-choices.md) - [5.1.3 Religious Food Choices](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-3-religious-food-choices.md) - [5.1.4 Food Labels](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-4-food-labels.md) - [5.1.5 Mandatory Food Labels](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-5-mandatory-food-labels.md) - [5.1.6 Optional Food Labels](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-6-optional-food-labels.md) - [5.1.7 Marketing Influences](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-7-marketing-influences.md) - [5.1.8 End of Topic Test - Food Choice](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-1-8-end-of-topic-test-food-choice.md) - 5.2 British & International Cuisines - [5.2.1 British Cuisine](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-2-1-british-cuisine.md) - [5.2.2 Japanese Cuisine](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-2-2-japanese-cuisine.md) - [5.2.3 Japanese Ingredients & Dishes](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-2-3-japanese-ingredients-and-dishes.md) - [5.2.4 Spanish Cuisine](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-2-4-spanish-cuisine.md) - [5.2.5 Spanish Ingredients & Dishes](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-2-5-spanish-ingredients-and-dishes.md) - 5.3 Sensory Evaluation - [5.3.1 Taste Receptors & Olfactory Systems](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-3-1-taste-receptors-and-olfactory-systems.md) - [5.3.2 Sensory Testing Methods](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-3-2-sensory-testing-methods.md) - [5.3.3 Sensory Testing Methods 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-3-3-sensory-testing-methods-2.md) - [5.3.4 End of Topic Test - Cuisines & Senses](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/5-3-4-end-of-topic-test-cuisines-and-senses.md) ### 6 Food Provenance - 6.1 Environmental Impact & Sustainability of Food - [6.1.1 Food Sources - Intensive & Organic Farming](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-1-food-sources-intensive-and-organic-farming.md) - [6.1.2 Food Sources - Genetically Modified Crops](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-2-food-sources-genetically-modified-crops.md) - [6.1.3 Food Sources - Reared Food](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-3-food-sources-reared-food.md) - [6.1.4 Food Sources - Caught Food](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-4-food-sources-caught-food.md) - [6.1.5 Food & The Environment](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-5-food-and-the-environment.md) - [6.1.6 Food & The Environment 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-6-food-and-the-environment-2.md) - [6.1.7 Sustainability of Food](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-7-sustainability-of-food.md) - [6.1.8 Sustainability of Food 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-8-sustainability-of-food-2.md) - [6.1.9 End of Topic Test - Environmental Impacts](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-1-9-end-of-topic-test-environmental-impacts.md) - 6.2 Food Processing & Production - [6.2.1 Primary Food Processing](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-2-1-primary-food-processing.md) - [6.2.2 Primary Food Processing 2](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-2-2-primary-food-processing-2.md) - [6.2.3 Secondary Food Processing](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-2-3-secondary-food-processing.md) - [6.2.4 Fortification](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-2-4-fortification.md) - [6.2.5 Additives](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-2-5-additives.md) - [6.2.6 End of Topic Test - Food Processing & Production](https://senecalearning.com/en-gb/revision-notes/gcse/food-preparation/aqa/6-2-6-end-of-topic-test-food-processing-and-production.md)