Because of soaking, vitamin C is easy to oxidize and discolor, so it turns black, especially when it is alkaline at high temperature. Nutrients or substances in the skin will dissolve in water, so it will turn black.

Vitamin C is prone to necrosis at high temperature, and if you can't soak it in a thermos cup for a long time, some toxic substances in plants will be soaked out. Lemon contains a lot of vitamin C, which is easily oxidized. The content of vitamin C in dried lemon slices is definitely lower than that in fresh ones.

Lemon is rich in vitamin C, which has many functions, such as anti-bacteria, improving immunity, assisting the formation of bone collagen, etc. Drinking lemonade often can supplement vitamin C. Drinking 500-1000 ml of lemonade a day when you have a cold can reduce your runny nose, and the cold will spread quickly, especially when you have just caught a cold, you can recover without medicine.

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Precautions for lemonade

In the fruit area of big supermarkets, we can often see lemons with orange color and fragrant smell. Lemon itself is a fruit with high nutritional and medicinal value. Lemon is rich in citric acid and is known as the "citric acid warehouse". Besides sugar, the main nutrients in lemon are calcium, phosphorus, iron, vitamin B 1, vitamin B2, vitamin C and nicotinic acid.

The research results published at the annual meeting of the American Urological Society also show that drinking lemon juice can increase the level of citrate in urine, which can prevent minerals in urine from forming crystals in the kidney, that is, kidney calculi.

In addition to resisting bacteria and enhancing immunity, it also has the effects of stimulating appetite, promoting digestion, promoting fluid production to quench thirst and relieving summer heat. What is even less well known is that lemon can also expectorate, and its expectorant effect is stronger than that of orange and citrus. Add warm water and salt to lemon juice and drink it to cough up the thick phlegm accumulated in the throat. At the beginning of a cold, you might as well use lemon and honey to flush, which can relieve sore throat and reduce discomfort such as dry throat.

Cut the lemon into thin slices and soak them in water. It is best to use warm water when soaking, which will help to preserve more nutrients in the lemon. Of course, you can also add lemon slices when drinking black tea and drinks.

It is worth noting that no matter how good the food is, you can't be unscrupulous when you eat it. Lemon is no exception. Many women drink a lot of lemonade every day for beauty and hurt their stomachs. Therefore, drink lemonade in moderation, and it should not exceed 1000 ml per day. In addition, because the pH value of lemon is as low as 2.5, people with hyperacidity and gastric ulcer should not drink lemonade.

References:

Baidu encyclopedia-lemonade