A green plum, a cup of yogurt, a dish of aged vinegar, a jar of pickled Chinese cabbage... sour smell can often be seen on the Chinese table. Writer Wang Zengqi once lamented in "Five Flavors" that "Shanxi people can really be jealous!" At the beginning of the article, he wrote that a few Shanxi people would drink three spoonfuls of vinegar before ordering at a restaurant, which would make the neighboring guests stare in surprise. If Shanxi is an expert in sour food, then Guangxi, Guizhou, Yunnan, Northeast China and other places are masters of making sour food into various flavors. As the saying goes in Guizhou, 'If you don't eat acid for three days, walk around and run around', it shows the local people's obsession with acid. What magic does acid have that makes people so 'dizzy'? What health codes are hidden in sourness? Among the "Five Flavors", "Sour" ranks first. Regarding the "Five Flavors", whether it is commonly referred to as "sour, sweet, bitter, spicy, salty" or "sour, bitter, sweet, spicy, salty" in traditional Chinese medicine, "Sour" ranks first. What the hell is this? Acid is one of the oldest seasonings in human history, which can stimulate taste and smell, producing a strong sensory experience Bi Yanxia, Deputy Chief Nutritionist of the Nutrition Department at Beijing Friendship Hospital affiliated with Capital Medical University, introduced that in the early stages of human cooking with fire, salt free seasoning was used. Natural sour foods in nature, such as green plums, bayberries, and sour dates, can blend the fishy taste of meat. Therefore, natural acidity has become the first seasoning for humans. From the perspective of modern nutrition, when food is ingested orally, the base of the tongue in the mouth is the taste buds, and the acid sensing nerves of the taste buds are located at the forefront, which makes people more sensitive to acidity. Spring is the first of the four seasons, and the corresponding organ for spring is the liver. The liver is responsible for 'acidity', which ranks first among the five flavors and is also related to it Zhao Xin, Deputy Chief Physician of the Sub Health Department at Dongfang Hospital of Beijing University of Traditional Chinese Medicine, introduced that the Yellow Emperor's Inner Canon mentions that "acid enters the liver", and the liver is responsible for regulating the flow of qi. The astringency of sour taste can regulate the liver's function of qi release, preventing it from being overly excited, which is of great significance for maintaining the balance of yin and yang in the human body. Experts explain that sourness originates from acidic substances in food, with hydrogen ions being the active ingredient. There are three main sources of common sour taste: natural acid, fermented acid, and synthetic acid. Natural acids mainly come from natural plum fruits, such as green plums, bayberries, sour dates, lemons, hawthorns, blueberries, etc. The acidic substances contained in them are mostly fruit acids; Fermented acid mainly includes vinegar and lactic acid. The former includes mature vinegar, rice vinegar, white vinegar, balsamic vinegar, apple vinegar, persimmon vinegar, etc., while the latter includes pickles, pickled Chinese cabbage, yogurt, cheese, etc; Synthetic acids are artificially synthesized, such as tartaric acid. In cooking, "acid" as a seasoning can have many wonderful uses: adding a little vinegar when cooking fish or lamb can effectively remove the fishy smell; Adding some vinegar when cooking greasy food can relieve greasiness and stimulate appetite, greatly increasing one's appetite; Dip a little vinegar into dumplings to enhance their aroma and flavor, making them even more delicious; Adding vinegar when cooking shredded potatoes and other ingredients can make the taste of the dish more crisp and refreshing; For ingredients with high anthocyanin content, such as purple cabbage, cooking with vinegar can make the color more vibrant... Removing fishy smell, enhancing aroma, relieving greasiness, and improving freshness, the sour taste adds a unique flavor to the dish. Sourness plays an extremely special role in Chinese seasoning Bi Yanxia said that sourness can be combined with various flavors, whether it is the refreshing sweetness of sour and sweet, the stimulating pleasure of sour and spicy, or the mellow and rich flavor of salty and sour, they can all be transformed into mouth watering deliciousness. China has a vast territory, and people from different regions have different dietary habits and preferences for taste. However, no matter where you are, the unique taste of sourness always wins people's love. If you eat too much acid, you will be careful to hurt your liver. pickled Chinese cabbage fish is fresh, tender and smooth. Hot and sour powder is a powerful appetizer. Hot and sour soup warms up the appetizer. The sour soup is fat but not greasy. The fried snail with sour bamboo shoots has a unique flavor. The fried minced meat with sour beans is usually served at home. The Starch-coated quick-fried Chinese cabbage with vinegar wow gold with vinegar is fresh and delicious... The sour taste has conquered the taste buds of countless diners with its unique charm. Sour foods are not only unique in flavor, but also nutritious. Moderate consumption of sour foods is beneficial to the body Bi Yanxia introduced that for those with loss of appetite, sour foods can promote gastric acid secretion, increase appetite, improve digestive function, and supplement various nutrients. For example, sour fruits such as lemon, kiwi, orange, and tangerine are rich in antioxidants such as vitamin C, which can enhance the body's resistance and promote the absorption of nutrients such as iron. In addition, sour foods also contain minerals, trace elements, dietary fiber, protein, etc. For example, pectin in apples can promote intestinal peristalsis and improve constipation. Yogurt not only provides rich calcium and protein, but also contains lactic acid bacteria that help regulate the balance of the body's microbiota and promote intestinal health. Traditional Chinese medicine believes that sour taste entering the liver can nourish the liver blood and nourish the muscles and meridians Zhao Xin introduced that moderate consumption of sour foods can soothe the liver and regulate qi, alleviate emotional fluctuations, and improve symptoms such as chest tightness and rib pain caused by liver depression and qi stagnation. Sour taste has a astringent and astringent effect, which can prevent excessive leakage of body fluids. When sweating or nocturnal emissions occur, consuming sour food or medication appropriately can help to astringent and stop sweating, astringent and nocturnal emissions. Although sourness is delicious, it is also necessary to control the intake and not be greedy Bi Yanxia reminds that excessive intake of sour foods may corrode tooth enamel and irritate the gastrointestinal tract. Patients with gastrointestinal diseases, such as chronic gastritis and gastric ulcers, who have symptoms such as belching, acid reflux, and stomach pain, should not consume too much sour food to avoid worsening symptoms; Foods with strong acidity, such as lemon and hawthorn, can be paired with other ingredients and consumed in small amounts to reduce irritation; For those with poor gastrointestinal function, refrigerated yogurt can be stored at room temperature and warmed before consumption; Some sour foods are salted or made with a large amount of sugar or salt. Patients with hypertension, renal insufficiency and diabetes should try to avoid or reduce consumption. Eating too sour can harm the liver Zhao Xin stated that according to traditional Chinese medicine theory, sour taste enters the liver. Overconsumption of sour taste can cause excessive liver qi and digestion of the spleen, which can easily lead to symptoms such as loss of appetite, bloating, and diarrhea. In addition, overeating sour taste may also cause muscle spasms, leading to emotional fluctuations or restlessness. For people with a cold and damp constitution, excessive consumption of sour foods may exacerbate the cold and dampness in the body, leading to symptoms such as joint pain. What are the precautions for people with different constitutions when consuming sour foods? Zhao Xin introduced that people with a cold and damp constitution have insufficient yang energy and heavy dampness. Sour foods have astringent properties and may aggravate dampness in the body, so it is not advisable to eat too much. This group of people can eat moderate amounts of warm and moist foods such as ginger and lamb, and mix them with a small amount of sour foods for seasoning. People with heat constitution have high yang qi, often with dry mouth, bitter mouth, constipation and other symptoms. Eating sour food in proper amount can clear away heat, reduce fire, generate fluid and quench thirst, but it should not be excessive to prevent injury to the spleen and stomach. Sour fruits such as lemon and grapefruit can be eaten in proper amount, while fermented sour food such as pickled Chinese cabbage should not be eaten in excess. Healthy sour eating, away from rumors of pickled Chinese cabbage in the northeast, sour beans in Anhui, red sour soup in Guizhou, sour bamboo shoots in Guangxi, dregs and vinegar hot pot in Hainan, sour rice noodles in Yunnan... When these sour foods enter the kitchen, what are the ways of cooking? Bi Yanxia pointed out that when cooking sour food, it is necessary to pay attention to the following points based on the characteristics of the ingredients: vinegar is easy to evaporate at high temperatures and lose its sour taste, so it is best to add it before the dish is cooked or taken out of the pot; Lemon's acidity and aroma are easily volatile at high temperatures. It is recommended to slice or squeeze the juice before adding it to the dish to avoid prolonged cooking; Tomato sauce is suitable for burning, stewing, and stir frying, and can add color and sweetness; Pickles, pickled Chinese cabbage and other pickles should be placed with moderate salt during pickling, and the amount of salt should be reduced without affecting the taste and shelf life; Pickled foods such as pickles and pickled Chinese cabbage are suitable for frying and stewing, which can increase the sour taste. However, harmful substances such as nitrite may be produced during pickling, so it is necessary to ensure sufficient pickling time to reduce the nitrite content, and fully soak and clean before cooking; Hawthorn is suitable for stewing and boiling, which can increase its sour and sweet taste and nutritional value. Many people are aware of the distinction between acidic and alkaline foods, but often equate sour foods with acidic foods. Some people are worried that eating too much sour food will make the blood in the human body sour and form an acidic constitution. Is there any scientific basis for this statement? Sour food and acidic food are completely different things Bi Yanxia explained that the acidity or alkalinity of food is not based on its taste, but on whether the substances produced after digestion, absorption, and metabolism in the human body are acidic or alkaline. If there are more phosphate, sulfate, chloride ions, etc. produced after food metabolism, an acidic reaction is formed; If a large amount of sodium ions, potassium ions, etc. are produced, an alkaline reaction will occur, which is closely related to the mineral content in food. Generally speaking, foods with high levels of minerals such as sulfur and phosphorus are acidic foods, such as grains, cereals, eggs, meat, etc; Foods that contain more minerals such as potassium, magnesium, and calcium are mostly alkaline foods, such as vegetables, fruits, and beans. According to Bi Yanxia, after food enters the human body, it is digested, absorbed, and metabolized to produce various products, including acidic, alkaline, and neutral. However, the acidity and alkalinity of food itself have minimal impact on the acid-base balance of the human body's internal environment, as the body has a complete buffering and regulating system that can keep the pH value of healthy people's blood constant at 7.35-7.45, and generally does not change due to the intake of food. There are rumors online that vinegar soaked food can soften blood vessels and lower blood pressure. Is this true? Vinegar mainly contains acetic acid and a small amount of organic acids and amino acids, which are beneficial for promoting gastric acid secretion. However, soaking food in vinegar or drinking more vinegar to soften blood vessels and lower blood pressure is not scientific Bi Yanxia stated that vascular sclerosis is mainly caused by lipid deposition and inflammatory reactions, and acetic acid does not affect blood lipid levels or inflammatory reactions. After vinegar enters the human body, it will be rapidly metabolized. Acetic acid in the small intestine will be neutralized by alkaline digestive juices. There is very little acetic acid that can enter the bloodstream, and it will be quickly cleared by the stable system of the blood, without changing the pH of the blood or softening blood vessels. The improvement of blood lipids and blood pressure requires overall lifestyle adjustments, such as healthy diet, regular exercise, smoking and alcohol restriction, weight maintenance, and rational medication. It is not enough to rely on a single food, nor can it ignore medical advice for medication. (New Society)