Life is closely related to chemistry. Milk and soybean milk are rich in protein, which can be combined with heavy metal ions before human structural protein poisoning, thus alleviating poisoning symptoms.

Protein in cooked milk has been denatured, and the detoxification effect is poor. (1) Why do raw persimmons taste astringent?

No matter who was born in the north or the south, people will have such a life experience: persimmons that are red as fire on persimmon trees are still inedible. At first taste, it is still very astringent. Is this persimmon not fully ripe? Yes, but if persimmons are fully ripe, it is not good for people to pick, transport and store them. Therefore, people often pick the persimmon when it turns red, and put it for a while, and it becomes a sweet and fragrant persimmon.

So, why does persimmon have astringency?

It turns out that this is because raw persimmons contain tannin (also called tannic acid), which makes persimmons astringent.

In order to get rid of the astringency of raw persimmons, people have come up with many ways in their constant life practice. Some people cover persimmons layer by layer with straw or pine needles, or bury persimmons in leaves with pears. After a period of time, the astringency of persimmons is gone. Some people directly scald persimmons with hot water, and the astringency of persimmons is naturally removed. Now people have adopted the "carbon dioxide deastringency method", which is actually a summary of people's past life experience. People seal persimmons in a room to increase the indoor carbon dioxide concentration and reduce the oxygen concentration. In this way, persimmons can't breathe normally, but breathe in the absence of oxygen. In the case of anoxic breathing, organic substances such as acetaldehyde and acetone will be produced inside raw persimmon. These organic substances can turn water-soluble tannins into water-insoluble substances, so persimmons are no longer astringent, but sweet and fragrant.

If you also have a few raw persimmons that want to "get rid of astringency", you can put them in plastic bags and tie them tightly. Generally, the astringency can be removed in a few days.

How did the golden banana come from?

Students in the far north can also eat delicious, fragrant and sweet bananas in the south. Do you know why?

As we all know, bananas are a special product of the south. Born delicate, untouchable. If it is not done well, it will rot in batches, and raw bananas will not mature automatically. What can we do?

Don't worry, first of all, bananas are easy to break and rot when cooked, so in order to transport bananas from remote southern Xinjiang to all directions,

E-commerce database 1'(8.5). * "-People can't wait until bananas are ripe, but harvest them when they are not ripe. At this time, the banana skin is green, and a lot of starch in the body has not been converted into glucose and fructose, so the "body plate" is very tough and doesn't care if it collides. This kind of banana is convenient for long-distance transportation.

The bananas delivered to the destination are still green skin and hard meat, and the taste is both astringent and not sweet. Of course, they cannot be sold in the market. Not when it's mature. Of course, people will find a way. The banana has been picked from the tree, and it has lost its ability to mature itself.

So, people found a way. They pumped gaseous ethylene (C2H4) into the warehouse where bananas were stored, which enhanced the activity of oxidoreductase in bananas and solidified water-soluble tannins. At the same time, chlorophyll in the peel disappeared, and blue-green bananas became popular in Huang Chengcheng. The pulp also becomes soft and gives off a fragrant smell. Bananas are ripe!

Ethylene can not only make bananas and other fruits mature, but also make rubber produce more rubber milk, and tobacco ripens early. This is really a magical gas.

Why is "bad fishing" sweet?

Students living in the south must know what "fishing bad" is, and it also has a name called liqueur. Although it smells like wine, it is not wine. It is made of timid rice or indica rice.

As we all know, rice is the main food for our people. Rice contains about 7% protein, and the main nutrient is 77% starch. These starches are the main source of human thermal energy.

We cooked rice, made medicated wine (commonly known as distiller's yeast) while it was hot, and made wine at the table. After nearly a day of heat preservation, we opened it and found that the taste changed, sweet and mellow, and it was very delicious. This is what the south calls sweet wine.

Why does rice become sweet wine after adding wine and medicine?

As we know, starch, glucose and other carbohydrates are all carbohydrates, and they are similar in molecular composition. Starch molecules are composed of many small molecules of glucose.

The medicated liquor contains amylase, which can promote starch hydrolysis and convert starch into sweet maltose. Amylase also exists in human saliva. When we chew rice in our mouth for a long time, we will feel sweet, which is the process of converting starch into maltose.

When making wine, maltose is converted into glucose by maltose invertase contained in medicinal liquor, and the other part is fermented into alcohol. In this way, the originally bland rice turned into a sweet liqueur.

(2) Stinky tofu is a kind of food that people like. "Smelling stinky and eating fragrant" is the unique flavor of stinky tofu. Stinky tofu tastes better. Students who have never eaten stinky tofu can't imagine why such stinky tofu has so many diners. If you hold your nose and bite the bullet and try bravely, you won't ask why.

It turns out that stinky tofu stinks, but it is delicious. No wonder its smell can't stop.

Stinky tofu is made by processing soybeans into tofu with less water content and then inoculating Mucor seeds for fermentation. Stinky tofu is produced in summer, when the fermentation temperature is high and the protein in tofu is completely decomposed. The sulfur-containing amino acids decomposed by protein are further decomposed to produce a small amount of hydrogen sulfide gas. Hydrogen sulfide has a pungent smell, so stinky tofu smells strong.

And because protein in tofu is decomposed more thoroughly, stinky tofu contains a lot of amino acids. Many amino acids taste delicious. For example, the ingredient of monosodium glutamate is an amino acid called glutamic acid. So stinky tofu tastes extremely delicious and smells abnormal.

Stinky tofu is a patented product of China! Many famous foods are related to stinky tofu. For example, fried stinky tofu is a particularly famous snack.

Competition between alcohol yeast and baking powder

In our life, the dough for making cakes and steamed bread is usually fermented by adding yeast or yeast powder, so that the cakes and bread made will be looser and more delicious. Which is better, yeast or yeast powder?

Let's analyze it first.

Yeast contains a certain amount of maltase and sucrase, which cannot directly change a large amount of starch in flour. Flour itself contains a small amount of amylase, which can hydrolyze starch into maltose;

2(c6h 10o 5)n+nH2O NC 12 h22o 1 1

Starch maltose

Then, enzymes in yeast play a role in promoting the hydrolysis of trace sucrose originally contained in flour and newly produced maltose:

c 12h 22 o 1 1+H2O c 6h 12o 6

Sucrose glucose fructose

c 12h 22o 1 1+H2O & amp； n

E-commerce database 3! 76 14003 $ 3/+ 1bsp； 2C6H 12O6

Maltose glucose

Yeast uses the energy provided by the oxidation of glucose and fructose to convert two sugars into carbon dioxide and water:

C6h12o6+6H2O → 6co216H2O10 calories.

The generated carbon dioxide gas can't leave the gluten network. When heating and steaming, carbon dioxide gas expands when heated, making the cake much bigger.

The food made by yeast is soft and delicious, with unique flavor and easy digestion. Yeast itself is rich in protein and vitamin B, which can increase the nutritional value of the finished product. So most flour products are fermented by yeast.

However, yeast fermentation often fails to achieve the expected effect on dough containing more sugar and oil, because sugar and oil have inhibitory effects on yeast. In addition, yeast fermentation takes a long time and is not done well. Either the dough doesn't rise, or the dough is sour and fermented too much. So you can also use baking powder instead of yeast to make cakes.

Baking powder is generally a mixture of sodium bicarbonate (NaHCO3, also known as baking soda) and sodium dihydrogen phosphate (NaH2PO4), and ammonium bicarbonate (NH4HCO3) is also useful. When yeast powder is mixed into dough, it generates carbon dioxide gas when heated, which makes flour products become loose and porous sponges. When used, the baking powder is not limited by fermentation time and can be used at any time, so it still plays the role of foaming and loosening dough containing oily polysaccharides. The disadvantage is that its alkalinity will destroy the vitamins in the dough, reduce the nutritional value, and also cause uneven mixing, resulting in too much alkali in some parts of the flour products and yellowing, which is inedible.

It can be seen that the two have their own advantages, but generally speaking, people always use yeast to ferment.

(3) Don't let the color confuse your eyes.

We often see gold fonts or patterns on plastic diaries, binders and other items. This kind of gold lettering or pattern is ironed with gold powder. Is this gold powder made of gold? Of course not. Gold is so expensive that people will never use it to grind powder to decorate ordinary products. So, what is gold powder made of?

It turns out that the gold powder is made of copper-zinc alloy-proud silver copper. It's the same color as gold. People made brass in the Han dynasty, which was later called "fake gold", and the law at that time explicitly prohibited its use. We know that copper is purplish red, zinc is silvery white, and their alloy brass is as shiny as gold in Huang Chengcheng. Gold powder is made by mashing and polishing a thin piece of brass and a small amount of lubricant. Gold powder is widely used in paint and ink.

It's not made of silver. Silver powder is made of aluminum, which is very cheap and has the same silvery white luster as silver. Aluminum powder is light in weight, stable in air, strong in light resistance and strong in light reflection ... This series of advantages makes aluminum powder win the title of "silver powder". There are two ways to make aluminum powder. One method is to mix pure aluminum flakes with a small amount of lubricant and then mechanically mash them. Another method is to melt pure aluminum into liquid (aluminum).

Low melting point, only 660℃), and then sprayed into fine aluminum powder.

A Misnamed "Moth Pill"

Clothes and books are in the cupboard. After a while, I opened the cupboard door and took a look. Ah, all good clothes and books have holes! Who did this?

This is dried by catfish, which mainly eats clothes and books, so people often call this moth "clothing fish". In order to get rid of these bad guys, people always put some "mothballs" in cabinets or boxes. Camphor is volatile and has a strong smell. When the octopus smelled it, it had to retreat and run away.

However, camphor is more expensive and has more important uses in medicine (preparing cardiotonic agent) and chemical industry (making celluloid plastics). Therefore, the daily "moth balls" are not made of camphor, but of naphthalene.

The molecular composition of naphthalene is C 10H8. Pure naphthalene is a colorless flaky crystal, which, like camphor, can be directly evaporated into gas for sublimation. The smell of naphthalene can also stimulate octopus, so it is a good insect repellent.

Naphthalene is extracted from coal tar and is cheaper than camphor. However, you should pay attention to the use, and the sanitary balls you buy at any time are not very pure. It also contains some coal tar, which will stain clothes. Therefore, when using, the sanitary balls should be wrapped in paper respectively, and then put into the cupboard or suitcase. After complete volatilization, the residual coal tar impurities will be absorbed by the paper and will not cause any trouble to the clothes.

A cathartic-phenolphthalein

Anyone with a little knowledge of chemistry knows that dropping one or two drops of a certain solution in platinum hydroxide aqueous solution will immediately show a bright red color. This is the famous indicator-phenolphthalein. If a certain amount of sulfuric acid is added to the red solution, the red solution will become colorless again.

Phenolphthalein is one of the most commonly used acid-base indicators, which is soluble in alcohol when used. It will turn red when it meets alkaline solution, but it is still colorless in neutral or acidic solution.

However, people who have studied chemistry may not all.

E-commerce database; ; #27")4 13.- (.Yes, phenolphthalein is a good medicine for doctors! In medicine, phenolphthalein is a laxative. Phenolphthalein can gently stimulate intestinal wall, enhance intestinal peristalsis and promote defecation, which is very effective for habitual constipation. The "Fruit Guide" contains phenolphthalein.

How to remove the scale on the water bottle

Boiling pots and thermos bottles often contain a layer of khaki scale. How did it come about? What's the impact on us? How to get rid of it?

Tap water looks clear and transparent, without dust and sediment. However, after the tap water is boiled, calcium bicarbonate and magnesium bicarbonate dissolved in water will undergo decomposition reaction to generate calcium carbonate and magnesium carbonate precipitate:

Ca(HCO3)2 CaCO3↓+H2O+CO2

Mg(HCO3)2 MgCO3↓+H2O+CO2

Over time, a layer of scale was formed at the bottom of the kettle. The scale accumulated at the bottom of the pot will affect the heat transfer and cause the waste of fuel. In particular, well water and river water containing more calcium bicarbonate and magnesium bicarbonate are more likely to form scale.

When calcium carbonate and magnesium carbonate precipitate from small particles to large particles, other metal ions in water will also precipitate. According to research, the contents of heavy metals harmful to human body such as aluminum, platinum and chromium contained in scale are dozens or even hundreds of times higher than those in water. If the thermos bottle with scale is filled with wine or other acidic food, harmful impurities in the scale will dissolve into the food. So the scale must be washed off in time.

The method of washing scale is very convenient. Based on the strong acidity principle of acetic acid and carbonic acid, a small amount of hot acetic acid is put into a thermos and shaken for a while, and then a chemical reaction occurs, and the precipitation will be eliminated.

In this way, the solution in the thermos bottle is poured out, and then washed with clear water several times, and the metals harmful to the human body are washed away.

Eggs and milk-first aid for poisoning

Perhaps you have heard that eggs, milk and soybean milk can be used as first aid drugs for poisoned patients. What is the reason?

Eggs, milk and soybean milk are nutritious and contain a lot of protein. Protein has a characteristic that heavy metal ions, such as mercury and aluminum, will precipitate. When heavy metal ions enter the human body, protein, which constitutes human organs and blood, will precipitate and lose its function, leading to poisoning. At this time, after giving patients milk, raw egg white and soybean milk, protein rich in food will interact with heavy metal ions, thus reducing the toxicity of poisoning. At the same time, these foods also provide nutrition for patients who are poisoned and weak, and help patients recover. Eat: salt (NaCl), vinegar (CH3COOH), sugar (c12h2o11). ...

Wear: polymer organic matter: fiber: polyethylene, polyvinyl chloride. ...

Site: marble house (CaCO3), cement (mixture) ... You can choose a small aspect, such as the harm of chemical fiber to human body. When you find the starting point, you can find the specific information. ! !