Vinegar can be roughly divided into three types, namely brewing vinegar, synthetic vinegar and white vinegar.

According to the classification of raw material treatment methods, raw vinegar is made directly from grain raw materials without cooking and gelatinization. The vinegar brewed after cooking and gelatinization is called clinker vinegar. According to the classification of saccharified koji used in vinegar making, there are bran koji vinegar and old koji vinegar. According to the classification of acetic acid fermentation methods, there are solid fermented vinegar, liquid fermented vinegar and solid diluted fermented vinegar. According to the color of vinegar, there are strong vinegar, light vinegar and white vinegar. If classified by flavor, the vinegar taste of aged vinegar is stronger; Smoked vinegar has a special burnt taste; Chinese herbal medicines and plant spices are added to the sweet vinegar.

Synthetic vinegar, also known as vinegar essence, is diluted with edible glacial acetic acid. It has a strong vinegar taste, but it has no fragrance. Glacial acetic acid has a certain corrosive effect on human body, so it should be diluted when used. Generally speaking, the content of glacial acetic acid should not exceed 3-4%. This kind of vinegar does not contain various nutrients in vinegar, and it is not easy to go moldy and deteriorate; But because it has no nutritional function, it can only be seasoned, so if there is no special need, it is better to be jealous.

vinegar

Vinegar, also known as vinegar, acyl, bitter wine and rice vinegar, originated in China. During the Spring and Autumn Period and the Warring States Period, Zhou Li recorded that "acyl group is the main acyl group" and "acyl group" refers to sour products such as vinegar. From this calculation, vinegar has a history of more than 3000 years. The climate of products in China is different, which leads to different characteristics of vinegar in different places, such as Zhenjiang vinegar in Jiangsu, Shanxi mature vinegar, Baoning bran vinegar in Sichuan and Kazuo mature vinegar in Liaoning. "Chinese Medicine Grand Ceremony" records that "Hangshao County, Zhejiang Province produces the best vinegar, while Zhenjiang, Jiangsu Province actually produces the best vinegar". Zhenjiang aromatic vinegar is a typical rice vinegar with glutinous rice as raw material. Tao Hongjing recorded the usage of Zhenjiang rice vinegar in Shen Nong's Notes on Materia Medica. Accordingly, Zhenjiang aromatic vinegar has a history of 1400 years.

Due to the different raw materials and production methods, the finished products of vinegar also have different flavors. Vinegar is a kind of acid condiment which is widely used. The content of acetic acid in 100mL vinegar is above 3.5g in general vinegar and above 5g in excellent vinegar. Because vinegar can improve and regulate human metabolism, it is in increasing demand as a dietary condiment.

There are four kinds of raw materials and production methods of vinegar.

(1) The raw materials of traditional fermented vinegar in China are mainly glutinous rice and rice (japonica rice) in the south of the Yangtze River and sorghum and millet in the north of the Yangtze River. Nowadays, broken rice, corn, sweet potato, dried sweet potato, potato and dried potato are used as substitutes. Raw materials are cooked, gelatinized, liquefied and saccharified to convert starch into sugar, then ethanol is produced by yeast fermentation, and then ethanol is oxidized by acetic acid bacteria to produce acetic acid.

(2) fermented vinegar, a sugar-containing raw material, can be used to brew all kinds of juice vinegar from grapes, apples, pears, peaches, persimmons, dates and tomatoes, and honey and molasses can also be used as raw materials. They all only need to go through two biochemical stages: ethanol fermentation and acetic acid fermentation.

(3) Using ethanol as raw material, adding acetic acid bacteria for fermentation is only one biochemical stage. For example, it takes only 1 ~ 3 days to brew wine vinegar with low-alcohol liquor or edible alcohol diluted with water as raw materials by rapid brewing method.

(4) White vinegar is vinegar with a flavor similar to that of fermented vinegar by adding water to edible glacial acetic acid and adding seasonings, spices, pigments and other substances.

Magical use of vinegar

Soften fish bones: Adding a little vinegar when cooking fish can make fish bones soft and delicious.

Peel the egg: before boiling the egg, add some vinegar to the water, and it will be easy to peel the egg after cooking.

Soften meat: when frying meat or pure meat, add a spoonful of white vinegar to soften the meat and cook it quickly; Take the meat to be thawed out of the refrigerator, dip it in vinegar first, and cook it after about an hour. The meat will be tender and delicious.

Desalinate the salty taste of pickles: when pickles are too salty, add vinegar to make them salty and delicious.

Fish does not rot: after the fish is cut open and washed, it will be dehydrated and soaked in vinegar, so that the fish will not taste bad for a long time and the vinegar will not become turbid.

Peel raw fish: put raw fish in vinegar, and the skin can be peeled off from the meat soon.

Fried egg skin: fried egg skin should be cooked with low fire, and eggs should be beaten with vinegar, which can make eggs thin and elastic.

Fish-fried non-stick pan: If the newly bought pan is washed with vinegar, fish-fried non-stick pan.

Boil kelp: add vinegar when cooking kelp, it will be easy to cook thoroughly and delicious.

Edema patients: Drinking vinegar often can treat edema or relieve pain.

Detumescence: before the affected area is slightly swollen and suppurated, wipe it with cotton dipped in vinegar to reduce swelling.

Treatment of insomnia: drink a cup of cold water and add a spoonful of vinegar before going to bed, and you will fall asleep easily.

Treatment of headache and dizziness: covering your forehead with a hot towel soaked in vinegar can treat headache and dizziness.

Delicate skin: applying the mixture of vinegar and glycerin to the skin can make the skin tender and smooth.

The first beriberi: soak the affected area 15 minutes with a mixture of a little vinegar and 40-degree hot water for two weeks.

Make-up is more beautiful: after washing your face, wash it with a basin of clear water and a spoonful of vinegar, and then wash it with clear water, so that your makeup is more beautiful.

Polish your shoes: If you want to polish your shoes very brightly, you can add one or two drops of vinegar to the shoe polish to achieve the effect.

Polishing of bronze and silver: Wipe with vinegar to keep it bright for a long time.

Glassware polishing: One tablespoon of vinegar, two tablespoons of ammonia (that is, ammonia water) and half a basin of water are mixed together to wipe glassware and furniture, which can be particularly bright.

Glossy plush products: Take a large basin of clean water, add a few drops of vinegar, and rinse the washed plush clothes to increase the luster of plush products.

Clothes do not fade: after washing clothes, stir with water and a little vinegar, so that colored clothes do not fade.

Flatten wrinkles: the hem of clothes is too short, and the wrinkles are not easy to flatten after stretching. You can smooth them with vinegar.

Remove stains from ceramic utensils: (1) It can be cleaned with a mixture of vinegar and salt. (2) Put it in water with a few drops of vinegar, and it will be decontaminated.

Washing socks: adding a small amount of vinegar when washing socks can not only sterilize but also deodorize.

Remove paint stains: after painting, if there are paint stains left on doors, floors, etc. They can be wiped off with hot vinegar.

Deasphalting: If the hands and feet are polluted by asphalt, you can wipe them with vinegar first, and then clean them with soap and warm water.

Deodorization: After the onion is cut and washed, the pungent smell will remain on your hands. If you don't go for a long time, you can wash it off with a little vinegar.

Ten Benefits of Drinking Vinegar

Vinegar can be roughly divided into three types, namely brewing vinegar, synthetic vinegar and white vinegar. The largest number in China is fermented vinegar. Scientific analysis shows that fermented vinegar contains not only 5%-20% acetic acid, but also organic acids such as amino acids, lactic acid, succinic acid, oxalic acid and nicotinic acid, minerals such as protein, fat, calcium, phosphorus and iron, vitamin BI, vitamin B2, sugar and aromatic substance ethyl acetate. The content of organic acids and amino acids in rice vinegar made from rice is the highest.

Modern medicine believes that vinegar has the following functions in treating diseases and preserving health:

1, eliminating fatigue;

2. Adjust the acid-base balance of blood and maintain the relative stability of human internal environment;

3, help digestion, which is conducive to the absorption of nutrients in food;

4, anti-aging, inhibiting and reducing the formation of peroxide in the process of human aging;

5. Strong bactericidal ability, which can kill staphylococcus, Escherichia coli, dried bacteria, halophilic bacteria, etc. In the intestine;

6. Enhance liver function and promote metabolism;

7. Dilating blood vessels is beneficial to lowering blood pressure and preventing cardiovascular diseases;

8, enhance renal function, have diuretic effect, and can reduce urine sugar content;

9, can make the body's excess fat into physical exertion, and promote the metabolism of sugar and protein, which can prevent obesity;

10, vinegar also contains anticancer substances.

Who invented vinegar and why is it called "vinegar"? Legend has it that in ancient China, that is, Yuncheng, a man named Du Kang invented wine. His son Heita also learned wine-making technology from Du Kang. Later, Heita led the clan to move to Zhenjiang, Jiangsu. There, they felt it was a pity to throw away the distiller's grains after brewing, so they stored them and soaked them in jars. On 2 1, as soon as I opened the jar, a smell that I had never smelled before came to my nose. Under the temptation of rich fragrance, Heita tasted it, which was sweet and sour, so it was stored as a "sauce". What is the name of this sauce? Heita named this sour water "vinegar" and added the word "one" to the number 2 1. It is said that until today, the time limit for brewing a batch of vinegar in Zhenjiang Hengshun Sauce and Vinegar Factory is still 2 1 day.

Chemistry: Since ancient times, people have understood that wine naturally oxidizes in the air and "turns sour into vinegar". This process is essentially fermentation. The basic principle of vinegar production by fermentation is similar to that of wine production. Just mix the unsterilized alcohol products obtained after saccharification and alcoholization with bran, chaff, acetic acid bacteria and so on. And then ferment. The temperature is controlled at 40℃ in the early stage and at 36℃ in the later stage. After about 40 days, the acetic acid content reaches more than 5%, and it is mature when it no longer rises. At this time, under the catalytic oxidation of acetic acid bacteria, ethanol became acetic acid:

C2H5OH+O2CH3COOH+H2O

Vinegar contains about 5-6% acetic acid. Generally, vinegar fermentation can only be carried out in yellow rice wine, wine and other alcoholic beverages, because acetic acid bacteria need nitrogen and phosphorus as nutrients. It is generally impossible for soju or pure alcohol solution to ferment to produce acetic acid. In the long-term social life practice, our people have created a variety of ways to produce vinegar, and the variety of vinegar in China is the first in the world, among which Shanxi vinegar and Guangdong white vinegar are the most famous.

Vinegar has become a mixture with the unique taste of our people. It can also be used to help digest food and prevent colds and colds. But the acetic acid contained in vinegar is far more than these functions.

Acetic acid, also known as acetic acid, is abbreviated as HAC, and AC stands for acetate. It is a colorless liquid with a strong pungent smell (here refers to concentrated acetic acid with a little water, and our vinegar only contains about 5-6% acetic acid, so it does not have the above characteristics), with a specific gravity of 1.049, a boiling point of 1 18℃ and a melting point of 65438. When the room temperature is lower than 16.5℃, acetic acid will crystallize like ice, so more than 6% acetic acid is also called glacial acetic acid. Glacial acetic acid absorbs moisture easily, which will burn the skin and cause dehydration.

Generally, we get dilute acetic acid solution through fermentation, which is only suitable for eating. In order to obtain high concentration of acetic acid, wood dry distillation or organic synthesis must be used.

Acetic acid is made by dry distillation of wood, which we introduced before. This is a comprehensive utilization method. It takes mountain bark, branches, roots or sawdust from a wood factory as raw materials, and heats them in a closed container isolated from the air to make them undergo a series of physical and chemical changes, and finally obtains three products: solid, liquid and gaseous. The solid is charcoal, the gas is wood gas (mainly composed of CO, CO2 and CH4), and the liquid product is distillate oil, which contains wood tar and wood acetic acid and is easy to clarify and separate.

The separated wood acid contains acetic acid, methanol and acetone. After adding lime, acetic acid is neutralized into calcium acetate. Because methanol and acetone have low boiling points, they are easy to separate after heating. The remaining CaAc2 was distilled with concentrated sulfuric acid to obtain 60% acetic acid.

Synthesis is the main method of mass production of acetic acid in modern times. Oxidizing acetaldehyde with air or oxygen in the presence of manganese acetate as a catalyst;

People have also found an industrial method to produce acetic acid from petrochemical industry, and oxidation of hydrocarbons, an important product of petroleum and other chemicals, is an important direction to synthesize acetic acid in industry at present.

Recently, it has been found in practice that the carbonylation of methanol and CO at 175 ~ 254℃ and under the action of special catalyst to synthesize acetic acid is also a new process worthy of attention.

We have learned a lot about the industrial production methods of acetic acid, but don't forget its numerous industrial uses. It is also an important fresh force of chemical raw materials in our modern industrial production. It is mainly used to make synthetic fiber (vinylon), cellulose acetate (as raw material of photographic film and rayon), medicine (such as aspirin), dye (indigo), pesticide (2 or 4 drops) and so on. ) and other chemical products. In addition, acetate can be used as a solvent for paint. Buffer solutions of acetic acid and sodium acetate are also used in agriculture (such as soil analysis and cultivation of agricultural microorganisms).

Seasoning vinegar

Chinese New Year in the north, every household eats jiaozi dipped in vinegar, which has a unique flavor. But do you know who invented vinegar?

Two or three thousand years ago, there was a wise man named Du Kang (also known as Du Shaokang) in Yuncheng, China, who was very good at making wine and was called "Brewmaster". The dregs left by brewing-called distiller's grains-have a strange smell. Du Kang often asks his son to give them to others to feed animals.

One year, the Chinese New Year was coming, and all the neighbors asked Du Kang to help them make wine. Before going out, Du Kang said to Du Jue, "I'm going out for a few days. The wine is steamed and can be used to treat distiller's grains. " Du Xun thought, now that everyone is preparing for the new year's goods, who wants distiller's grains? So, put your distiller's grains into a big barrel, add some water, cover it, and prepare to feed the horses.

However, the Spring Festival is coming, and there are many things. When he is busy, he will forget it. After 20 days, Du Jue had a dream when he slept at night: an old fairy with a white beard asked him for sauce. He said, "Where is the sauce?" The old fairy pointed to the vat where the distiller's grains were soaked and said, "Isn't this it?" You can eat it tomorrow, and it has been packed for 2 1 day! "In ancient times, the unitary time was from five to seven in the afternoon.

The next day, Du Jue woke up and felt that the dream was very strange. In the evening, my father Du Kang hurried home for the New Year. Du Yi told his father, and Du Kang found it very interesting. The two men went to the vat and opened the cylinder head. Ah, a stream of sour gas rushed up, stinking! Everyone in the family said, "Throw it away, or it won't work!" But Du Jue said, "Anyway, wine is drinkable, and this distiller's grains water can't kill people. Let me have a try. " He tasted the yellow water with the tip of his tongue, which was sour and thought it was not bad.

On the first day of the first month, the whole family eats jiaozi with relatives and friends. With the support of his father, Du Jue asked everyone to dip some yellow water in the jiaozi. As a result, everyone said while eating: hey, this tastes really good! Acid is sweet, refreshing and wonderful.

Yellow water became a condiment. What should we call it? Inspired by his dream, Du Xun combined the words "February 11th" into a word "vinegar". The saying that "Du Kang makes vinegar by brewing wine" circulated in Shanxi, China, tells this story.

As the saying goes: think about it day and night. Du Xun's dream is not really directed by an old fairy, but a subconscious reflection of his in-depth study on the application of distiller's grains water. Although I know nothing about ancient fermentation, I know from practice that distiller's grains water will change and become vinegar after being stored for a period of time. This is absolutely correct.

Now besides Shanxi vinegar, there are many kinds of vinegar in other places, such as rice vinegar, koji vinegar, bran vinegar, wheat vinegar, peach vinegar, plum vinegar and jujube vinegar. The function of vinegar is not only a condiment, but also a supplement to other daily necessities. If the clothes are contaminated by fruit juice, it is easy to wash them off with a few drops of vinegar. When washing your hair, add some vinegar to the water, and your hair will be darker and smoother after washing. Add some vinegar to the bathtub when taking a bath. After washing, the body can quickly eliminate fatigue. In short, there are many examples of using vinegar in life.

Thank you!