4hw.com.cn: peanut oil is a kind of edible oil that is easy to digest. Peanut oil can provide a lot of nutrition for human body and increase the taste of food. Many people like it very much. So how to judge whether peanut oil is adulterated?
Is peanut oil vegetable oil
Peanut oil is of course vegetable oil.
Vegetable oil is a compound composed of fatty acid and glycerin, which is widely distributed in nature. The oil obtained from the fruits, seeds and plumule of plants is called vegetable oil. Such as peanut oil, soybean oil, flax oil, castor oil, rapeseed oil, etc.
Characteristics of peanut oil
Peanut oil is composed of 20% saturated fatty acids and 80% unsaturated fatty acids, mainly oleic acid, linoleic acid and palmitic acid, with iodine value of about 80-110. It is a dry oil, light yellow and transparent, fragrant, and is a high-quality cooking oil. According to the national standard GB 1534-2003 peanut oil, peanut oil can be divided into leached peanut oil and pressed peanut oil. Leached peanut oil is extracted by solvent, and pressed peanut oil is made by pressing method.
In 2004, China began to implement the food safety market access system, and all kinds of peanut oil sold should have QS mark.
How to judge whether peanut oil is adulterated and look at the price
The lowest cost of producing 1 kg peanut oil is about 14 yuan. Whether peanut oil sold below this price is adulterated is obvious.
Quality standard of peanut oil
The peanut oil can be divided into two levels: the first level of pressing and the second level of pressing. There is basically no fine filtration equipment in small workshops, and the oil produced is crude oil. The marked super level and the first level sold by small workshops are inferior.
Sense of seeing
The peanut oil extracted from fresh peanut has a natural color, bright golden yellow, and a natural rich fragrance of peanut oil. If you use rotten or summer peanut kernel squeezed out of the peanut oil color Ze dark.
Smell it
Dip a little oil with your right finger, rub it in your left heart for a few times, and smell it immediately. It can be regarded as the top grade if it has strong and pure peanut oil fragrance and no abnormal taste. The peanut oil mixed with flavor has a slight peanut flavor, but with the rubbing again, the smell of peanuts will fade.
Look at the solidification temperature
Put peanut oil in the refrigerator for about 10 minutes. If the oil solidifies, it can be preliminarily identified as mixed with palm oil. Put it into the refrigerator for about 30 minutes. If the oil is stratified and solidified, it can be preliminarily determined to be mixed with rapeseed oil. The freezing point of peanut oil is 0-3 ℃, palm oil is 27-30 ℃, and canola oil is - 12-10 ℃.
Practical inspection
The high-quality peanut oil color is light yellow at room temperature, clear and transparent; the smell and taste are normal, and the oil color will not change deep after heating to 280 degrees, without precipitates; the color, smell and taste of poor peanut oil are abnormal, with large water content, many impurities, rancidity and scorching odor. Therefore, good oil does not smoke at low temperature.