FATS AND OILS

Learning Objectives Understand the different types and uses of fats and oils in food preparation - functions. Name some of the different fats and oils. Explain how fats ‘shorten’ pastry.

Think Tank Sources of Fat There are 3 sources of fat What do you think they are?

Sources of fat: Animals Fish Vegetables

Think Tank Types of Fat There are 5 types of fat What do you think they are? How will they be used in the diet?

Can you name some fats and oils available to the consumer? Butter – made from churning cream It provides 80g of fat per 100g. An alternative is ghee often used in Indian cooking (it is heated and then clarified) Lard – from pigs fat It provides 99g of fat per 100g. It is usually softer than butter in consistency and and white in colour. Suet – made from fat that surrounds animals organs, It has a similar fat content to that of lard. Soft spreads – blended from vegetable oils. The oil is hardened by adding hydrogen gas. Vegetable oil – mainly produced from oil seeds e.g. sunflower seeds or from the flesh of some fruits like olives. Reduced or low fat spreads contain 40-80% less fat. They have a higher water content and so are not suitable for cooking methods. They are an emulsion of water and oil

Think Tank Classification of Fat Fats are classified as either saturated or unsaturated Which is the healthier? A high intake of cholesterol has been linked to which long term conditions?

Saturated vs Unsaturated Found in Lard, butter, suet and some vegetable oils We should consume less of these as they contain more cholesterol than other fats. Unsaturated Found mainly in vegetable oils e.g. cooking oils

Heart Disease

Stroke

Think Tank Properties of Fat - 1 Fats have a 9 properties or functions in food? How many can you name?

Property of Fat 1 Fat Aerates Food – when fat is creamed with sugar it helps to trap air

Property of Fat 2 Fat Extends the shelf-life – makes the product last longer for baked products and it helps to retain the moisture in the product.

Property of Fat 3 Fat Flavours and Odours – Gives foods such as biscuits a distinct taste and smell.

Property of Fat 4 Fat creates a Flaky texture to pastry – helps to separate the layers by creating steam.

Property of Fat 5 Fat can create an Emulsion – oils form an emulsion with liquids such as vinegar e.g. salad dressings.

Property of Fat 6 Fat adds Colour – scones form a ‘shine’ once cooked

Property of Fat 7 Fat helps prevent lumps forming in a sauce.

Property of Fat 8 Fat stops food from sticking and lubricates.

Property of Fat 9 Fat acts a cooking medium

Properties of Fat and Oils Aerates food – when fat is creamed with sugar it helps to trap air. Extends the shelf-life – makes the product last longer for baked products and it helps to retain the moisture in the product. Flavours and Odours – Gives foods such as biscuits a distinct taste and smell. Flaky texture to pastry – helps to separate the layers by creating steam. Emulsion – oils form an emulsion with liquids such as vinegar e.g. salad dressings. Colour – scones form a ‘shine’ once cooked Helps prevent lumps forming in a sauce. Shortening – Provides a shortening ability to the mixture and changes the texture. For example fats give shortbread its characteristic crumbly and short texture. It stops food from sticking and lubricates.

Think Tank Properties of Fat - 2 Fats have a shortening effect in pastry and biscuit mixtures How would you describe the texture of a short biscuit e.g. shortbread Consider Crumbliness Qualities in the mouth

Shortening Fats have a shortening effect in pastry and biscuit mixtures. This happens when fat coats the flour particles preventing absorption of water (a waterproof coating). This prevents gluten, the protein found in flour from developing, this is what helps give bread a stretchy and elastic texture. If this process is unable to take place it results in a short, melt-in-mouth crumbly texture.

Thursday’s practical Shortbread 100g Soft Margarine 50g Caster Sugar 150g Plain Flour 15-20 minutes cooking time Gas Mark 5 / 180oc