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How to distinguish the quality of oil?
How to distinguish the quality of oil? How to distinguish waste oil?

When buying edible oil, be sure to check whether the production process is "squeezing method" or "leaching method" on the outer packaging. The pressed oil can retain the fragrance of the oil itself, keep the original nutritional components of the raw materials, and the quality is relatively pure. It is recommended to buy. Generally speaking, the sensory identification of edible vegetable oil mainly starts from five aspects: seeing, smelling, tasting, listening and asking. The quality of edible oil was investigated from four aspects: color, aroma, taste and shape. A look: first look at transparency. Pure oil should be transparent. In the production process, due to the mixing of alkaline grease, wax and impurities, the transparency will decrease. Second, look at the color, pure oil should be colorless, in the production process, because the pigment in the oil is dissolved in the oil, the oil is colored; The third is to look at the sediment, commonly known as oil feet, the main component is impurities, and it sinks to the bottom of the oil under certain conditions. When buying oil, it is best to choose oil with high transparency, light color (except sesame and gutter oil) and no sediment. Second smell: Each oil has its own unique smell. Open the lid of the oil drum and you can smell it when your nose is close. You can also drop a drop or two of oil on your palm, rub your hands together and smell it carefully while it is hot. The oil with peculiar smell indicates that there is something wrong with the quality; Oil mixed with mineral oil smells like mineral oil and can't be bought. The third taste: use clean chopsticks or glass sticks, take one or two drops of oil, apply it to your tongue and taste it carefully. Oil with sour taste is unqualified, oil with bitter taste has been rancid, and oil with peculiar smell may be adulterated oil. Listen 4: Listen to the sound of burning, the purpose is to identify whether the water content exceeds the standard. Take one or two drops of oil from the bottom of the reservoir, spread it on flammable paper, ignite it and listen to its sound. If the combustion is normal and silent, and the moisture content is less than 0.2%, it is a qualified product; If the combustion is abnormal and squeaks, the moisture content is above 0.2%, which is unqualified product; When burning, "Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Beep Bee The above sensory identification methods of edible oil are only for consumers' reference when purchasing edible vegetable oil. Distinguishing gutter oil is not complicated. Generally speaking, gutter oil is dark in color, looks turbid and smells strange, while normal cooking oil is not only clear, but also smells slightly fragrant. As long as citizens don't patronize those unlicensed restaurants with extremely poor sanitary conditions, they won't eat in hogwash fat.

Teach you how to distinguish good cooking oil from bad cooking oil.

Sanhuang: An important way to test the quality of edible oil is to shake the oil bottle, which means that the bubbles will melt quickly, indicating that the quality is better.

Four flavors: take a drop of oil with chopsticks and taste it. The sour oil is unqualified.

Five Listening: Take one or two drops of oil from the bottom of the oil layer, spread it on paper, light it and listen to its sound. If the combustion is abnormal and crackles or squeaks, the quality is unqualified.

Six questions: ask the merchant about the purchase channel and ask for the invoice. Excessive cooking oil can induce lung cancer.

How to distinguish the quality and quality of edible oil

Vegetable oils that are often eaten mainly include soybean oil, rapeseed oil, peanut oil and cottonseed oil, and their quality identification mainly includes the following points. Transparency: Explain the refining degree of oil and the removal degree of phosphorus-containing valves.

High transparency, less moisture and impurities, good quality. Good vegetable oil, after standing for 24 hours, should be clear and transparent, not turbid, not precipitated and not suspended.

Color: Good quality soybean oil is dark yellow, generally light yellow; Rapeseed oil is yellow, slightly green or golden yellow; Peanut oil is light yellow or orange, and cottonseed oil (sanitary oil) is light yellow.

Smell: Touch a little oil with your finger and rub it on your palm. It smells good after rubbing. Good quality oil should have its own oil flavor according to different varieties, and it can't have other strange flavors, even rancid and spicy.

Taste: Dip chopsticks in a little oil and put it in people's mouths to distinguish their tastes. They should have the unique taste of this product, and should not have bitter, astringent, burnt, rancid and other peculiar smells.

How to tell the quality of gasoline! ! Detailed! ! !

Methods of distinguishing gasoline quality;

1, smell gasoline. Good gasoline has a strong smell. On the contrary, gasoline mixed with water will make the smell very weak. There is also impurity gasoline. Adding some impurities leads to a special smell of gasoline.

2. Look at the color. Good gasoline is light yellow, gasoline with ginseng water is white and transparent, gasoline with impurities is dark orange, and gasoline with too many impurities is turbid.

How to identify the quality of lubricating oil?

At present, the lubricant market is full of fake engine oil of various brands, more than 50% of which are fake and shoddy, and the proportion of steam engine oil for automobiles is higher, so it is difficult to buy good engine oil! 20-Fake engine oil sold in 80 yuan 100-400 yuan and above, many people take risks for profiteering, which seriously damages the interests of car owners, causing the car to break down once every three days, making many car owners want to cry! Don't be afraid, having our "critical eye" will make you see the oil market clearly and clearly.

Look, look at the oil package. Authentic licensed goods are beautifully packaged, and there are special signs in inconspicuous places such as the bottom of the tank, the inside of the tank cover and the handle; Most of the fake packaging is rough, the color is generally lighter than the genuine one, the genuine one is clear at the code spraying place, and the fake one is not necessarily clear.

Second, look at the color of the oil. Authentic new oil is light yellow, crystal clear, without impurities, suspended solids, precipitation and uniform flow; Used waste engine oil is black and shiny, just like a mirror, and its viscosity is as thick as new engine oil.

Three smells, no special smell, only a slight fragrance. Fake oil usually smells like gasoline and diesel when you open the oil drum. The engine oil with strong sense of smell and smell is deteriorated or inferior, and it is absolutely not allowed to be used. The weight of real oil is generally accurate, while the number of barrels of fake oil is quite different.

Four frozen, if possible, pour half a bottle of engine oil into a transparent container and seal the bottle mouth, and tie it tightly with multiple fresh-keeping bags to prevent the engine oil from leaking and polluting the refrigerator. Oil is poisonous. If you put it in the freezer for a few hours, it must still be flowing at a low temperature of -20 degrees, and it must not be frozen, otherwise it will be fake engine oil.

Five dozen, check the phone number.

Liu Liu, don't trust anyone. Oil drums must be taken away to facilitate claims; If you find a fake, you must call 123 15 to report it and tell everyone you know. He can take a fake oil pit. You are no longer your "friend".

If it can't save you money and time, it must be fake.

How to distinguish the quality of rapeseed oil?

Identification of rapeseed oil:

1, which can be divided into pressed rapeseed oil and leached rapeseed oil according to the preparation process.

2. According to whether the raw materials are genetically modified, they can be divided into genetically modified rapeseed oil and non-genetically modified rapeseed oil.

3. According to the erucic acid content in fatty acids, it can be divided into general rapeseed oil and low erucic acid rapeseed oil.

Generally dark yellow or brown. Rapeseed oil contains 0.4- 1.0% arachidic acid, 0.4-19% oleic acid, 0.2-24% linoleic acid, 3 1-55% erucic acid and 0/-linolenic acid. In terms of nutritional value, the digestibility of rapeseed oil can be as high as 99%, which is beneficial to gallbladder function. When the liver is in pathological state, the human body can also metabolize rapeseed ketone normally. Rapeseed oil lacks essential fatty acids such as linoleic acid, and its fatty acid composition is unbalanced, and its nutritional value is lower than that of ordinary vegetable oil. In addition, rapeseed oil contains a lot of erucic acid, glucosinolates and other substances, which are generally considered to be unfavorable to human growth and development. If it can be eaten with high-quality edible oil rich in linoleic acid, its nutritional value will be improved

How to distinguish the quality of soybean oil

Identifying the quality of soybean oil mainly includes the following aspects:

1. color recognition

Pure oil is a colorless, transparent and slightly viscous liquid. In the sensory evaluation of soybean oil color, the samples were mixed evenly, filtered, and then poured into a beaker with a diameter of 50 mm and a height of 100 mm, and the height of the oil layer should not be less than 5 mm. Observe under natural light at room temperature. Then put it in front of a white background and observe it through reflected light. When the oil thickens or solidifies in winter, take about 250 grams of oil sample, heat it to 35℃ ~ 40℃, and then cool it to about 20℃, and identify it according to the above method.

Good soybean oil-yellow to orange; Inferior soybean oil-the color of oil is brown to brown.

2. Identification of transparency

For the sensory evaluation of the transparency of soybean oil, the fully mixed sample of 100 ml was placed in a colorimetric tube, and then observed by the reflected light in front of a white background. ?

High quality soybean oil-completely clear and transparent.

Secondary soybean oil-slightly turbid, containing a small amount of suspended matter.

Inferior soybean oil-the oil is turbid, with a lot of suspended solids and sediments.

3. Smell recognition

Sensory identification of soybean oil odor can be carried out in the following three ways: 1. When the oil container is opened and sealed, put your nose close to the mouth of the container and smell its smell. The second is to take 1 ~ 2 drops of oil sample and put it on the palm and back of your hand. Put your hands together and rub them quickly until they get hot and smell. The third is to take about 25 grams of oil sample with a steel spoon. Heat it to about 50℃ and smell it with your nose near the oil surface. ?

High-quality soybean oil-has the inherent smell of soybean oil.

Inferior soybean oil-the inherent smell of soybean oil is dull, with a slight odor, such as grass.

Inferior soybean oil-has bad smells such as musty, burnt and spicy.

How to distinguish the quality of automobile oil killing

Braking is related to the safety of the owner, and you can't be careless at all. Brake oil is one of the key links. Here is a very simple way to help you identify the true and false brake oil used:

Pour a little brake oil into the palm of your hand and gently tap it with your fingers. If it is genuine and good brake oil, you will immediately feel the palm of your hand hot, and the more you rub it, the more you feel hot. If it is fake, the inferior brake oil will come slowly with little or no heat. In this case, it is recommended that the owner immediately empty and clean the brake oil of the whole vehicle and replace it with genuine brake oil to ensure safety!

It is also difficult for mechanics to tell good from bad. From the owner's point of view, what are the tips to distinguish the authenticity of brake oil? "Good brake oil is generally tens of dollars, and most of the brake oil with a few dollars has problems! However, to be honest, it is difficult for a mechanic to tell whether the brake oil is good or bad! " Many garage insiders pointed out. "Brake oil? Never bought it! I heard that it is very complicated! " "I didn't change it, I asked the repair shop to add it for me!" The garage pointed out that due to the cumbersome replacement, most consumers directly replace brake oil in the garage; Many car owners actually don't know when to change the brake oil, and most of them only change or add the brake oil at the reminder of 4S shops or garages.

1. Brake fluid is too thin to use, colorless and transparent to use? Generally qualified brake fluid is light yellow or dark yellow.

2. Choose big brands with reliable quality, and don't mix different brands.

It's too cheap to buy. Generally, the brake fluid per liter 10 yuan on the market is basically inferior. The price per liter of qualified domestic brake fluid is usually above 40 yuan, and the joint venture brand is more expensive.

There are many ways to use brake oil.

There are two kinds of braking methods for automobiles: oil braking and air braking. Oil brake system? Automobile hydraulic braking system is widely used not only in small cars, but also in heavy trucks because of its compact structure, small volume, large braking torque, uniform braking, rapid braking and low energy consumption, and can also prolong the service life of tires. Brake oil is automobile brake fluid. Is it used in oil braking system? Automobile hydraulic braking system transmits pressure liquid. Brake oil is the key link in the braking system. In order to ensure driving safety, the use and replacement of brake oil must not be careless, and care must be taken to pay attention to the following points.

1. When moisture is mixed or inhaled in the brake oil, or impurities or precipitates are found in the brake oil, it should be replaced in time or carefully filtered, otherwise the brake pressure will be insufficient, thus affecting the braking effect.

2. If the vehicle runs normally for 40,000 kilometers or continuously uses the brake oil for more than 2 years, the brake oil is liable to deteriorate due to long-term use, so attention should be paid to timely replacement.

3. When the vehicle is running normally, if the brake is light or heavy, the brake oil should be replaced in time, and the brake system should be cleaned with alcohol before replacement. 4. When the vehicle brakes deviate, check the braking system comprehensively. If it is found that the expansion of the cylinder cup is too large, it means that there may be a problem with the quality of brake oil. At this time, brake oil with better quality should be selected for replacement.

5. When changing seasons, especially in winter, if the braking effect is found to decrease, it may be that the level of brake oil does not adapt to the winter climate. At this time, when replacing new brake oil, it is necessary to choose low-temperature and low-viscosity brake oil.

How to identify the quality of olive oil

How to tell if the so-called extra virgin olive oil you bought is really "extra virgin"? First of all, consumers must know what real extra virgin olive oil is. According to EU regulations and international olive oil standards, extra virgin olive oil must be made of fresh olive fruit without damage, moth and mildew, and it must be completed within 24 hours from picking to pressing. It must be a purely physical cold pressing process, and it must be the first pressed pure natural olive oil. At the same time, only after strict legal procedures, the natural acidity is less than or equal to 0.8%, can it be called extra virgin olive oil. At the same time, the finished product can be canned immediately or sealed in a special stainless steel oil cylinder, and then stored at constant temperature. If canned products need to be produced within two years, the acid value and related indicators must be re-tested, and the standard is extra virgin olive oil, otherwise it will be eliminated.

Look at the label: the label must indicate the category. Is there a Spanish word "virgen extra" or an English word "extra virgin", which means "extra virgin", representing the highest grade of olive oil? "Cold pressing" or "cold pressing" means "cold pressing", which means that olive fruit is made by pure physical pressing at low temperature, natural and pure, and its nutritional components are not destroyed. Extra virgin olive oil can be eaten raw; Ordinary virgin olive oil should not be eaten raw; Refined or blended olive oil is extracted by chemical infiltration and cannot be eaten raw; Fruit pomace is forbidden to eat in the EU, and it is only used for biofuels and cosmetics. Then judge whether olive oil is purely imported and whether it is a brand sold in the market of the country of origin. Check whether the original label and the back label of the label are marked in the national language of the country of origin, because the manufacturer must make the label in the national language before it can be sold in the domestic market. As stipulated by the laws of China, imported goods sold in China market must be labeled in Chinese, otherwise sales are prohibited.

Look at the origin: Does the label indicate the origin and source of olive oil? The canned place of olive oil is not a place of origin.

Look at the acidity: What range of acidity is indicated on the label? According to EU regulations and international olive oil standards, the natural acidity of extra virgin olive oil is less than or equal to 0.8%, and natural nutrients are retained. The fake extra virgin olive oil can also reach this acidity standard after artificial chemical deacidification, and the lowest acidity can reach 0, and its natural nutrients are seriously destroyed.

Color: There are many colors of olive oil, ranging from yellow to green, which is caused by different fruit types of olive trees. Gold green or gold yellow is the best extra virgin olive oil. However, the natural pigments and other nutrients in refined olive oil are destroyed and the color is very light. There are also illegal manufacturers who add pigments to olive oil and deliberately confuse the concept.

Observation concentration: Extra virgin olive oil is bright, thick and shiny, and retains natural nutrients to the greatest extent. Oil mixed, lack of bright luster, indicating that it has been left for a long time and began to oxidize. The color is light and the oil feels very thin, indicating that it is refined oil or blended oil, and the natural nutrients are destroyed.

Smell: fruity. Different olive tree varieties have different flavors, such as grass flavor, licorice flavor and fruit flavor. This shows that the olive oil in your hand is completely cold pressed. If there is no smell, there must be chemical intervention to deodorize it. There are off-flavor, musty, muddy, sour, metallic and spicy flavors, indicating that the raw materials of olive fruit are deteriorated or improperly stored or have problems.

Taste: The taste is smooth, not greasy, and has a faint sweet, bitter and spicy taste. At the entrance, there is a clear feeling at the back of the throat, and the spicy feeling lags behind. Because consumers are not professionals after all, they are not too sensitive to sweetness or bitterness, but they can feel the pungent taste. Olive oil above the grade of virgin olive oil will have this feeling, and the higher the grade, the more obvious it is. This is also the most effective way for consumers to identify whether olive oil is really extra virgin olive oil. However, some unscrupulous manufacturers will also mark the oil marked with virgin olive oil grade as extra virgin olive oil for sale to deceive consumers. If it smells or has no smell at all, it must be refined olive oil or fruit residue, or even the most basic virgin olive oil. In short, olive oil with fresh fruit fragrance and a balance of sweetness and bitterness is a good oil, which is also a necessary condition for truly extra virgin olive oil.

Look at the barcode: There are two kinds of olive oil imported from China: original packaging and sub-packaging. The original packaging means that this bottle of olive oil is produced and canned in the exporting country; Sub-packaging is the value-added tax imported by domestic merchants. ......