Some nutrients have to be “sunscreened”

It is well known that many nutrients are afraid of heat, and high temperature cooking will accelerate their loss. Little known is that there are some nutrients that are afraid of light, so pay attention to “sun protection” when storing.

Vitamin K. Also known as coagulation vitamins, it promotes normal blood clotting. Lack of it can lead to weakened blood coagulation, which can lead to bleeding and even death in severe cases. Vitamin K can also promote bone metabolism and effectively reduce the risk of fractures. In addition, studies have found that adequate intake of vitamin K is beneficial to cardiovascular health and reduces the incidence of coronary heart disease. The main food sources of vitamin K are vegetable oils (such as rapeseed oil, soybean oil and safflower oil, etc.), green leafy vegetables, soybean products, offal, egg yolks and dairy products. Vitamin K is a fat-soluble nutrient, it is not particularly afraid of heat, and it will not be lost by dissolving water, but it has a particularly big weakness-afraid of light. Studies have shown that when vitamin K-rich canola oil is stored in a clear bottle, the vitamin K content is lost by more than 90% in less than 10 days; while in a dark bottle, about half of the vitamin K is lost after 36 days. Therefore, it is recommended to give priority to buying vegetable oil in dark bottles, and do not put it in a bright place such as the stove after you buy it. Other foods rich in vitamin K should also be protected from light.

Vitamin B2. Also known as riboflavin, it is an essential substance in protein, fat and carbohydrate metabolism. Vitamin B2 deficiency can cause inflammation and dysfunction of the mouth, lips, skin, and genitals, such as seborrheic dermatitis, oral ulcers, angular stomatitis, and dizziness. Its main food sources are dairy products, egg yolks, dark green leafy vegetables, etc. Vitamin B2 is afraid of alkali and light. Milk stored in a transparent glass bottle is irradiated with sunlight for 30 minutes, and 28% of vitamin B2 is destroyed, and 50% of it is destroyed after 90 minutes of irradiation. Therefore, the popular transparent bag of milk in recent years is not conducive to the preservation of nutrients such as vitamin B2. In addition, substances such as porphyrins in milk will generate reactive oxygen species under the excitation of light, and then react with proteins, vitamins and fats to produce components with poor flavor and affect the taste of milk. It is recommended that you prefer milk in opaque plastic bags or cartons.

Vitamin C. Also known as ascorbic acid, it is one of the most demanded nutrients in the human body, and it has various health benefits, such as anti-oxidation, increasing human immunity, and improving the utilization of iron, calcium and folic acid. The main source of vitamin C is fresh fruits and vegetables, such as kiwi, fresh dates, bitter gourd, peppers, spinach, grapefruit, strawberries and oranges. Vitamin C is more squeamish, it is afraid of heat, light, oxygen, alkali, and easily lost with water. Generally speaking, the fresher the fruits and vegetables, the more vitamin C content, the longer the storage, the less the content, especially in a light environment, it will accelerate its loss. When storing fruits and vegetables, try to avoid sunlight exposure, and put them in the refrigerator for better cooling effect.

(Source: China Food and Drug Network)