How to distinguish gutter oil from cooking oil?

According to experience, edible vegetable oil can generally be identified by five aspects: looking, smelling, tasting, listening and asking.

Take a look. Looking at the transparency, the pure vegetable oil is transparent, and the transparency will decrease due to the mixing of alkali lipids, waxes, impurities and other substances in the production process; Look at the color, the pure oil is colorless, in the production process because the pigment in the oil is dissolved in the oil, the oil will be colored; Looking at the precipitate, its main component is impurities.

Second sniff. Each oil has its own unique smell. You can put one or two drops of oil on the palms of your hands, and rub your hands together to heat up.

Smell it carefully. If there is a peculiar smell of oil, it means that there is a problem with the quality, and the smell is likely to be gutter oil.

If mineral oil is available.

The smell can not be bought.

Three tastes. Take a drop of oil with chopsticks and taste it carefully. Oil with a sour taste is an unqualified product, oil with a burnt bitter taste has become rancid, and oil with a peculiar smell may be "gutter oil".

Four listening: Take a drop or two of oil from the bottom of the oil layer, apply it to a flammable piece of paper, light it and listen to its sound. Qualified products are those that burn normally and silently; If the combustion is abnormal and makes a "squeak" sound, the moisture exceeds the standard, and it is an unqualified product; When burning, it makes a "crackling"** sound, indicating the moisture content of the oil.

Seriously exceeded, and may be adulterated, should never be purchased.

Five questions: ask the merchant's purchase channel, and ask for the purchase invoice or check the sampling test report of the local food safety supervision department if necessary.

Is cooking oil at home gutter oil? It's so practical to use this method to easily identify.

I'm the most expert and will teach you the three easiest tricks.

See. Looking at the transparency, the pure vegetable oil is transparent, and the transparency will decrease due to the mixing of alkali lipids, waxes, impurities and other substances in the production process; Tell me to tease.

Look at the color rotten and dissipated, the pure oil is colorless, in the production process because the pigment in the oil is dissolved in the oil, the oil will be colored; Looking at the precipitate, its main component is impurities.

Sniff. Each oil has its own unique smell. You can put a drop or two of oil on the palm of your hand, rub your hands together, and smell it carefully when it is hot.

If there is a peculiar smell of oil, it means that there is a problem with the quality, and the smell is likely to be gutter oil. If there is a smell of mineral oil, you can't buy it.

Taste. Take a drop of oil with chopsticks and taste it carefully.

Oil with a sour taste is an unqualified product, oil with a burnt bitter taste has become rancid, and oil with a peculiar smell may be "gutter oil".

There is a trick to identifying gutter oil, and it would be a pity not to know.

How to distinguish between edible oil and gutter oil? I have learned these tricks, and I can no longer buy fake oil, life skills, life tips, life skills, life tricks.

Isn't this nonsense about the identification method? When buying oil in the supermarket, you can only look at the outer packaging, **There are open and smell.

This is something that the country needs to do well, so that the people can learn to identify?

First of all, look at the color, bright, light color, uniform and no precipitation for good oil. (Condensation due to low temperatures does not count).

Next, drop a drop and rub it in the palm of your hand. Then smell it, the strange smell is gutter oil, and the fragrant oil is good oil.

If you eat it for a year, you will die with gutter oil, and if you don't die, it will be cooking oil.

If you don't have diarrhea after eating, it's not gutter oil.

Here's how I identified it, put it in the frozen layer of the refrigerator, and if it was frozen in a solid state, it was. The same is true for stir-fried vegetables, and when they are put in the refrigerator, the phenomenon of solidification is gutter oil.

Gutter oil has a white lumpy sediment on the third floor. You've never seen oil, right? I don't know, don't talk nonsense here.

I've eaten more than you've ever seen! The peanut oil I eat at home is 100% pure peanut oil processed from my own peanuts, and I haven't seen any precipitation for two years. Hehe, you've probably only seen gutter oil since birth, right?

So you don't distinguish between black and white, eat the magazines precipitated by gutter oil as protein, you speak for gutter oil, you won't just buy gutter oil, right? Otherwise, you just eat too much gutter oil and eat your brain, so you talk nonsense with your eyes open!

Put it in the refrigerator and see if there is any precipitation at 10 degrees, because gutter oil is generally mixed oil, with different freezing points, and it will be graded when frozen.

Please, the two upstairs have seen the oil.

Now which oil doesn't have white precipitation, that's protein precipitation.

There is a trick to identifying gutter oil, and it would be a pity not to know.

Four tricks can be distinguished:

1. Taste: If the oil taste contains spiciness, it is likely to be edible oil refined from gutter oil;

2. Distinguish peculiar smell: take a small amount of edible oil in the palm of your hand, rub it back and forth with your palm, if there is a peculiar smell, it is likely to be mixed with gutter oil;

3. Put it in the refrigerator: Put the oil in the refrigeration area of the refrigerator at 5 to 8 degrees Celsius, and after 2-4 hours, there will be solidification crystals, and it is likely to be gutter oil. Because in the gutter oil is added animal oil with a considerable composition of oil.

4. High fire: If the color of the oil changes after firing at high fire, and the color becomes thick and black, it is likely to be gutter oil, because the small particles contained in gutter oil are easy to change color after being burned.

5. Look at the transparency of the oil. Authentic cooking oil is clear and transparent, put a note on one side, from the opposite side in the light can clearly see the words on the opposite side, and the gutter oil must be turbid, the more mixed it, the more turbid the oil.

1.See.

The main purpose of looking at the transparency of the edible oil, usually pure vegetable oil is mostly transparent, this edible oil you can buy and eat with confidence. However, if the cooking oil looks cloudy, it means that the oil must be of faulty quality, or it is simply gutter oil. The reason for turbidity is that alkali lipids, waxes, impurities and other impurities are mixed into the production process.

In addition, we should also pay attention to the color of the edible oil, the pure oil is colorless, if the pigment in the oil is dissolved in the oil during the production process, then the oil will have some color. At the same time, it is necessary to pay attention to the sediment, pure vegetable oil will not have sediment.

2.Sniff.

By smelling, it can also help us quickly and effectively identify whether it is gutter oil, and it can be said that each edible oil has its own special smell. When smelling, you can put a drop or two of oil on the palm of your hand, then close your hands together and rub them together until your palm is hot, and then smell it carefully. If the smell is obviously pungent or abnormal, it means that the quality of the oil is wrong.

If there is a foul smell, it is likely to be gutter oil, and it is best to avoid buying this oil as much as possible.

Normally, the pure cooking oil aroma is very fragrant, and there will not be any peculiar smell in it, but if there is a foul smell or mineral oil smell, it means that there is a quality problem.

3.Listen

In our daily life, we can also identify whether it is gutter oil by listening, taking one or two drops of oil from the bottom of the oil layer and applying it to flammable paper, and then igniting it with fire. At this time, you can listen to its sound, if the combustion is normal and there is no sound, it means that it is a qualified product. If the combustion is not normal and the "squeak" sound is also emitted, it means that the moisture in it exceeds the standard and is an unqualified edible oil.

If there is a "crackling" sound during combustion, it means that the content in the oil is seriously exceeded.

To identify gutter oil, on the one hand, it can be preliminarily determined through sensory inspection, that is, through the color, odor and other aspects of gutter oil, and to accurately identify gutter oil, it is necessary to determine the physical and chemical properties of gutter oil, which can be tested separately such as moisture content, specific gravity, refractive index, saponification value, acid number, carbonyl value, peroxide value, iodine value, heavy metals, relative unsaturation of fatty acids, cholesterol, residue detection, oxidation products and other indicators to further determine gutter oil.

Gutter Oil Calculator. Whether it is gutter oil is calculated by pressing the product** and oil yield and the weight of the oil.

At present, there is no technology in China to distinguish the difference between gutter oil and pure oil, but it is said that when you put some ginger when stir-frying, the oil turns black is gutter oil.

It's really hard to distinguish this, but it's mainly about color.

Gutter oil, generally refers to all kinds of inferior oil in life, long-term consumption may cause cancer, great harm to the human body. The first is gutter oil in a narrow sense, that is, the oil that is simply processed and refined from greasy floating objects in sewers or leftovers and leftovers (commonly known as swill) from hotels and restaurants;

the second is the oil produced by the processing and refining of inferior pork, pig offal and pig skin;

The third is the oil used for fried food after being used more than a certain number of times, and then reused or reused after adding some new oil to it.

There is a trick to identifying gutter oil, and it would be a pity not to know.

Scientific identification of gutter oil, there is no good way in an era that pays attention to food safety, the ideal state is that you go down to the museum, take out a test paper and dip it into the dish, take it out after a while and compare it with the score, and then shout: "Shopkeeper, change the oil!" "However, the reality is that until now, scientists have not found an ideal means to detect and identify gutter oil.

Oil mixed with oil, the gods are sad, and the gods are difficult to separate it. Gutter oil has a history of more than 20 years, and even today, we can still see it in rural markets and markets at the interface between urban and rural areas, and we also feel that it has entered the big canteens. If calculated by tonnage, millions of tons of gutter oil should be digested every year.

I'm ashamed that we haven't been able to find a very effective technical means to identify this oil as gutter oil, and this oil is not gutter oil. When participating in a CCTV program, Hu Xiaosong, deputy dean of the College of Food Science and Nutritional Engineering of China Agricultural University, once said. Hu Xiaosong pointed out that the current detection methods have not yet overcome this technology, and it is impossible to scientifically distinguish the quality of oil, but the Ministry of Science and Technology of the People's Republic of China has set up a special project for this matter, and I believe that it will be able to use scientific means to distinguish the quality of oil in the near future.

1 4 Look at the face, normal oil is not sourced.

How to distinguish gutter oil bai from good oil, some people think that du is to look at the color of the shade, zhi or dao to see whether it is turbid, tell you inside.

It is impossible to distinguish from the appearance, and the fake oil will also be filtered with activated carbon to become very clear, and the color is almost the same as good oil, so it is incorrect, the best way is to take the pH value test paper to test it, it is more acidic, it must be gutter oil.

In terms of main chemical composition, gutter oil is not much different from ordinary edible oil.

However, the path of gutter oil is complex, and it will generally experience repeated pollution, and the best way should be fuel destruction.

Among them, the main substances harmful to the human body of gutter oil are generally:

1. Metal heavy metal ions are easy to cause poisoning reactions, including acute and chronic poisoning, especially chronic poisoning, which is particularly harmful.

2. It is easy to produce aflatoxin, which is a high carcinogen, which is very toxic and not easy to be detected.

3. Chemical decolorizer and chemical deodorant, which is the post-processing done by the gutter oil manufacturer in order to make the gutter oil look the same as the edible oil. Generally, chemical decolorizers and chemical deodorants are strong oxidants, which are harmful to the human body and easy to cause cancer.

Because the waste oil is maliciously manufactured, the degree of counterfeiting is extremely high, and it is difficult to make a direct identification without biochemical testing.

Three-word formula: see, smell, listen. One look is to carefully observe the color of the oil, the color of the oil is pure, and there will be no variegation.

Gutter oil, on the other hand, is variegated because some of the dirt in the gutter oil cannot be removed due to simple processing. Second, as we all know, the source of gutter oil is the trash can of the restaurant, and it is conceivable that the smell must be bad. And gutter oil though warp.