C.5.4

=Describe the effects of food processing on the vitamin content of food.= IB syllabus says: Most vitamins are unstable at higher temperature so will be affected by prolonged cooking.

The water soluble **vitamin C** is readily **broken down** by cooking or food processing because: 1. **High temperatures** **increases the rate of oxidation**, thus, breaking the bonds that holds the vitamin together. Vitamins containing C=C or -OH bonds are readily oxidised, leading to the breakdown of the vitamin involved.Boiling helps to break down cell walls and make them more permeable so the longer the vegetable is boiled in water the more vitamin C is “leached” from the cells This means that foods that are food processed or cooked contain far less vitamin C than before it was cooked. 2. The vitamin C is very **soluble in water**, causing it to leave the food.

Fat soluble vitamins, such as **Vitamin A**, D, E, K, are relatively more stable at high temperatures used during cooking and are n**ot broken down**.

Food processing methods may include commercial and domestic processing:canning, blanching, freezing, pasteurisation, dehydration, milling, boiling, cooking and cutting/peeling.

Stable vitamins include:
 * Folate
 * Thiamin
 * Vitamin C(broken down by cooking)

More stable vitamins include:
 * Niacin (vitamin B3)
 * Vitamin K
 * Vitamin D (can be destroyed by oxidation as a result of bleaching)
 * Biotin (vitamin B7)
 * Pantothenic acid (vitamin B5).
 * Vitamin A(not easily broken down by cooking)

Vitamin A **Not broken down readily** by cooking
 * Vitamin C roken down through cooking.**