Food Science Flashcards
What is gelatinisation?
When flour is mixed with a liquid and heated, the mixture thickens
What is dextrinisation?
When dry heat is applied to products e.g. bread, it causes the product to brown
What is caramelisation?
When the colour of sugar changes from white to brown when heated
What is shortening?
When fat is used in rubbed-in mixtures, the finished product will have a short crumbly texture
What is aeration?
The process of trapping air into a mixture to cause it to rise
What is plasticity?
The ability of a solid fat to soften over a range of temperatures
What is emulsification?
The process of using an emulsifier e.g. egg yolk, to prevent a mixture of oil and liquid from separating e.g. mayonnaise
What is coagulation?
When the protein in food sets
What is foam formation?
A foam is produced when eggs are whisked
What is gluten formation?
When making bread, strong flour with high gluten content is used to provide the structure for the bread
What is acid denature?
When acids are used to change the shape and structure of protein foods e.g. tenderise meat or provide a soft texture,
What is enzymic browning?
When fruit or vegetables go brown
What is oxidisation?
When fruit and vegetables are cut open and the cells are exposed to air
What is yeast?
A raising agent used in bread making to give the bread lightness and causes it to rise
What are chemical raising agents?
They include baking powder, bicarbonate of soda and self-raising flour. They can be used to make bread products rise.
How is air used in baking?
Used in whisked sponges, soufflés and meringues to give lightness to the mixture
How is steam used in baking?
Causes products that contain a lot of liquid to rise e.g. eclairs, choux pastries
Give reasons why we cook food
To destroy bacteria To make food less bulky To improve the keeping quality of food To make it easier to digest To develop flavour To destroy natural poisons in food To have hot food in cold weather To make it more colourful and attractive Textures are changed Variety in the diet The aroma in food is released
How is heat transferred by conduction?
Heat is transferred by contact with heat
How is heat transferred by convection?
Heat moves through the convection currents. The hot air rises and cool air falls.
How is heat transferred by radiation?
Direct rays pass from the heat source to the food
What are the names of the proteins found in wheat which form gluten?
Gliadin and glutenin
What happens in meat between 40 and 60 degrees?
The muscle fibres coagulate
What happens to meat after 60 degrees?
The fibres in the meat shrink
What happens in eggs at 60 degrees?
The egg white begins to coagulate
What happens in eggs at 70 degrees?
The egg yolk begins to coagulate
What is syneresis?
If eggs are heated too quickly the liquid from the egg separates out and the protein becomes tough.
