Stability of nutrients in food
|
Nutrient |
Stability Characteristics |
|
Vitamin A |
Quite stable during processing and cooking |
|
Vitamin D |
Very stable to heat but sensitive to exposure to air and light. |
|
Vitamin E |
Relatively stable except at deep frying temperatures |
|
Vitamin K |
Stable in cooking but sensitive to light. |
|
Thiamin |
Quite unstable to heat and alkaline conditions. Lost during refining of cereals. Dissolves in cooking water. |
|
Riboflavin |
Very sensitive to light: 50% lost from milk left in sun for 2 hours. |
|
Niacin |
Stable to most processing but leaches into cooking water. |
|
Vitamin B-6 |
Moderate retention during most processing. |
|
Vitamin B-12 |
Moderate retention, but losses occur when heated under acid and alkaline conditions. |
|
Folic acid |
Large losses can occur during cooking. Presence of copper aids |
|
Pantothenic acid |
Relatively stable during most home processing. |
|
Biotin |
Good retention during most home processing. |
|
Vitamin C |
Unstable. Losses occur from exposure to air, light, heat and copper. |
Saving the nutrients in food.
- Do not store fresh foods for long periods – purchase just enough to last a week or less, and eat soon after buying.
- Store foods in a cool, dark place.
- If slicing or chopping, keep the pieces as large as possible.
- When boiling, add the raw food once the water is already boiling.
- Use the smallest amount of cooking water possible.
- Cook all foods for the shortest possible time. (Especially in the case of vegetables, lengthy cooking causes large losses of nutrients).
- Do not use copper pots or utensils.
- Do not use baking soda to preserve the colour of vegetables, as this increases vitamin losses.
- Use cooking water and liquid from canned foods for gravies, sauces and soups.
- Microwave cooking, because it is quick and avoids the use of cooking water in most instances, is a good way to save nutrients.
