The oil squeezed at home is based on the ancient squeezing method and modern technology because of the small oil squeezing equipment. The vegetable oil obtained by this pressing method contains many nutrients such as monounsaturated fatty acids and polyunsaturated fatty acids, but the fresh and nutritious vegetable oil is easily oxidized by light, heat, enzymes and metal ions to form various oxides, which leads to rancidity and deterioration of oil. Under the condition of low temperature, dark and sealed storage, the shelf life of fresh nutritious vegetable oil is only more than two months, not more than 80 days.

The shelf life of pressed edible oil sold in supermarkets in major shopping malls is generally 18 months. In fact, this shelf life first means that it can be kept unopened for 18 months. Secondly, the edible oil produced in large quantities by enterprises has to go through warehousing, transportation, wholesale, promotion and retail. No manufacturer can guarantee that it can be sold within 80 days, and it is normal for edible oil to stay in circulation for half a year or even a year. Therefore, in order to have enough sales time, the manufacturer has set the target of edible oil 18 months shelf life.

Extended data

Sesame oil is the general name of small ground sesame oil and system sesame oil, that is, sesame oil with strong or obvious aroma. In the production process, the unique ingredients in white sesame seeds are converted into substances with unique aroma after being boiled at high temperature, thus producing the unique aroma of sesame oil, which is different from other vegetable oils, so it is named sesame oil. According to the different production technology, incense is not divided into two kinds: small ground sesame oil and made sesame oil.