What nutrients do foods lose during heat treatment? This is a question that interests many. In this article we will analyze the temperature sensitivity of vitamins, because each of them has its own thermal stability threshold.
Vitamin C is the most susceptible to heat treatment. Its destruction occurs due to the oxidation of the water-soluble vitamin with oxygen.
Vitamin C losses are especially high if you:
- cook food with the lid open;
- put food in cold water;
- when heated to 70 degrees Celsius, the vitamin content is significantly reduced or completely destroyed;
- keeping food hot;
- chopping and wiping products increases their surface area of contact with oxygen.
For example, cabbage loses up to 90% of vitamin C when cooked, up to 50% when stewed, and 20-30% when steamed.
B vitamins tolerate heat differently.
Thus, when cooking, vitamin B1 (thiamine) loses up to 45% of its benefits, when frying - up to 42%, and during stewing - up to 30%. It is also sensitive to low temperatures - when frozen, half of the vitamin B1 contained in the product is lost.
Vitamin B2 (riboflavin) is more resistant to heat treatment. When stewing, it loses only 10%, and when cooking – up to 43%.
The loss of beneficial properties of vitamin B3 (PP) ranges from 5 to 40%.
Vitamin B12 (cyanocobalamin) is unstable to heat treatment, especially in an alkaline environment.
Vitamin B9 (folic acid) suffers the most. Loss of benefit up to 80-90%.
But short-term cooking slightly enhances the effect of pyridoxine (vitamin B6).
Heat-resistant vitamins include fat-soluble vitamins - A, D, E, K. They retain their beneficial properties when heated to 100 degrees Celsius.
Heat treatment methods also affect the preservation of vitamins in products. The most gentle are steaming, stewing and baking. More destructive to vitamins are frying and frying.
In addition to vitamins, other compounds also impart beneficial properties to foods. Sometimes heat treatment is necessary for their formation or better absorption. With proper preparation, unstable elements can be preserved and the benefits of stable ones can be revealed.
Foods that are healthier when cooked:
Carrot. Carotenoids from boiled carrots are absorbed by the body 5 times better than from raw carrots. To obtain maximum benefits, the vegetable should be cooked for 10-15 minutes.
New potatoes. In its raw form, the root vegetable has little benefit or taste, but its skin contains a lot of potassium and vitamin C. Choose new potatoes and cook them with the skin on.
Fried onions. The vegetable is rich in vitamins C, group B and the antioxidant quercetin. Quercetin has antiviral effects and is beneficial for heart health. With short heat treatment, for example, sauteing or frying, the amount of quercetin in onions increases several times, and acidity decreases, which makes onions safer for the digestive tract.
Baked apple. Fresh fruit is a storehouse of vitamins and minerals, including vitamins C, P, E, group B, manganese, potassium and iron. During heat treatment, some of these substances are destroyed. But during baking, the content of pectin in apples increases - an antioxidant that prevents the formation of atherosclerotic plaques and stimulates the growth of beneficial bacteria in the intestines.
Stewed cabbage contains less vitamin C than raw cabbage, but it produces lactic acid, which improves metabolism and promotes the absorption of calcium. Therefore, it is good to combine stewed cabbage with foods rich in calcium, such as cheese, cottage cheese and other dairy products.
Resources: ndsmi.by; aif.ru; tea.ru
