First, the normal preservation method of fresh lemons
1. chemical preservation method. 1 supplies. 5% potassium permanganate solution, 5% bleaching powder solution, burnt honeycomb briquette residue or activated carbon, plastic woven bag. ② Preparation of preservatives. Soak the residue of honeycomb briquette combustion or activated carbon in 5% potassium permanganate solution for several hours, then take it out, drain the solution, air-dry it in a dark and ventilated place until it is half dry, and make it into small pieces or granules, which is the preservative. ③ Disinfection of plastic woven bags. Clean and disinfect the plastic woven bag with 5% bleaching powder and put it in the shade to dry. 4 bagging. Put the lemon and preservative together in a plastic bag according to the weight ratio of 4: 1, seal it, and store it at low temperature, preferably at 0℃- 12℃. Lemons can be stored in this way for 200 days.
2. Film preservation method (fruit preservative film). This is a coating preservative suitable for citrus, lemon and other fruits. ① formula. Candelilla wax 4.0 kg, oleic acid 1.2 kg, xylene 0.05 kg, ethylene glycol 0. 1 kg, sodium carbonate 0.2 kg, morpholine 0.9 kg and water 22.2 kg. 2 preparation methods. After the above materials are heated to 80℃ for melting, they are added into 80℃ hot water and stirred evenly. ③ Method of use. When in use, the lemon can be washed, dried, dipped with a film coating agent, and then stored at 10℃-20℃. The shelf life can be extended from 1-7 weeks to 10-20 weeks.
3. Omni-directional fresh-keeping liquid preservation method. American researchers have recently invented a universal fresh-keeping liquid for fruit preservation and obtained an American patent. According to reports, this multifunctional fresh-keeping liquid is prepared by adjusting the pH value to below 3.5 with 3% citric acid or 75%-80% food-grade orthophosphoric acid, and adding 30%-40% sucrose, 0.3% sodium benzoate or ascorbic acid and 0.03% calcium hydrogen phosphate. Using this fresh-keeping liquid can not only prevent fruit from fading, inhibit bacterial reproduction, but also prevent fruit from shrinking and cracking, keep the texture of pulp unchanged, increase the sugar content and taste as good as new.
Second, the therapeutic effect
1, lemon promotes fluid production to relieve summer heat and stimulate appetite.
Although the taste of lemon food is sour and slightly bitter, it can't be eaten raw or fresh like other fruits, but lemon peel is rich in aromatic volatile components, which can promote fluid production, relieve summer heat, stimulate appetite and strengthen the spleen. Summer is hot and humid, and many people are very tired. After working or studying for a long time, you often have a bad appetite. Drinking a cup of lemon soaked in water, the fresh and sour taste makes people feel refreshed and can open their appetite.
Lemon is often used as a seasoning for seafood in western food to remove the fishy smell, while Southeast Asian food is directly cooked with it to highlight its sweet and sour taste. Lemon is also essential among the roast ducks and geese loved by southerners in China.
2. It can prevent cardiovascular diseases.
Lemon is rich in vitamin C and vitamin P, which can enhance the elasticity and toughness of blood vessels and prevent and treat hypertension and myocardial infarction. In recent years, foreign research also found that green lemon contains an insulin-like component, which can reduce abnormal blood sugar levels.
3, often eat lemon to clear away heat and phlegm
Lemon can also resolve phlegm. Lemon peel has stronger expectorant effect than citrus. It is hot and humid in summer. If you don't pay attention to the diet, the internal dampness of the human body and the external dampness of the natural climate interact, and phlegm will be produced over time. So in summer, there is a lot of phlegm and my throat is uncomfortable. Adding warm water and a small amount of salt to lemon juice can successfully cough up the thick phlegm accumulated in the throat.
4. It has antibacterial and anti-inflammatory effects.
Lemon is rich in vitamin C, which acts like a natural antibiotic on human body. Has antibacterial, antiinflammatory, and immunity enhancing functions. You can drink more hot lemonade to maintain your health.
5, delay aging and inhibit pigmentation.
Lemon contains vitamin B 1, vitamin B2, vitamin C and other nutrients, and is also rich in organic acids and citric acid. Lemon is a kind of high alkaline food, which has strong antioxidant effect and is very effective in promoting skin metabolism, delaying aging and inhibiting pigmentation.
6, lemon "mother and child" to eliminate morning sickness
Cantonese, a work of traditional Chinese medicine in Guangdong and Guangxi, records: "Lemon is suitable for mother and child, and tastes extremely sour. Pregnant women are addicted to it because of liver deficiency, so it is suitable for mother. It is better to hide more than old when people bid, and juice can replace vinegar. " In other words, pregnant women can put some lemons beside the bed and get up in the morning to smell them, which can eliminate morning sickness.
Third, dietary taboos
1, lemon can't be eaten with seafood.
Seafood foods such as shrimp, crab, sea cucumber and jellyfish are rich in nutrients such as protein and calcium, while lemon contains more acid. If lemon and seafood are eaten at the same time, the fruit acid in lemon will solidify protein and combine with calcium to produce indigestible substances, which will not only reduce the nutritional value of food, but also cause gastrointestinal discomfort, so try to avoid eating lemon and seafood together.
Lemon and milk are grams.
Similarly, milk is rich in protein and calcium. Eating lemon and milk together will also affect the digestion of the stomach.
Lemon should not be eaten with carrot.
Because carrots contain ascorbic acid enzymes, eating them together will destroy vitamin C in lemons.
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