Chapter 4 - Ingredients - Fats Flashcards
What are the 5 major functions of fats in baked items?
- Add moistness and richness
- Increase tenderness by shortening gluten strands
- Increase keeping quality
- Add flavour
- Assist in leavening as a creaming agent or give flakiness in products such as puff pastry and pie dough.
What group of compounds are fats a member of?
Lipids. Technically, fats are triglycerides, which are molecules made up of 3 fatty acid chains attached to the 3 carbon atoms of a glycerin molecule.
What are lipids?
Lipids are organic compounds not soluble in water.
What are liquid fats called?
Oils
What is a saturated fat?
A fat that is normally solid at room temperature. Fatty acids consist primarily of long chains of carbon atoms to which hydrogen atoms are attached. If a fatty acid chain contains as many hydrogen atoms as it can possibly hold = saturated fat.
What is an unsaturated fat?
A fat that is normally liquid at room temperature. Fatty acids consist primarily of long chains of carbon atoms to which hydrogen atoms are attached. If the chain has empty spaces that could hold more hydrogen = unsaturated fat.
What is hydrogenation?
Hydrogenation - A process that converts liquid oils to solid fats (shortenings) by chemically bonding hydrogen to the fat molecules.
What are 2 purposes for hydrogenation?
- Produce fats with desired physical characteristics
2. Reduce the tendency of the fat to spoil or become rancid, by reacting with the oxygen in the air.
Between saturated and unsaturated fats, which are more likely to become rancid?
The more unsaturated a fat is, the more likely it is to become rancid. Saturated fats are more stable, because all the places along the carbon chain are filled by hydrogen atoms, which gives oxygen less opportunity to react with the fat.
What is an emulsion?
A uniform mixture of 2 normally unmixable substances, such as fat and water.
Why does butter curdle/break?
When butter curdles/breaks, it contains more water than the fat can hold.
What is shortening?
a) Any fat used in baking to tenderize the product by shortening the gluten strands.
b) White, tasteless solid fat formulated for baking or deep frying.
What are the three main types of shortening?
- Regular/All Purpose shortenings
- High ratio plastic shortenings / Emulsified shortenings
- High ratio liquid shortenings / liquid cake shortenings
What are Regular/All Purpose shortenings?
Basic, without emulsifiers, used for creaming methods and icings.
What are High ratio plastic shortenings / Emulsified shortenings?
Containing emulsifiers, used for high ratio cakes (cakes with high sugar:flour ratio). Do not cream well.
