1. Try to buy products with high brand awareness and market share from commercial enterprises with a certain degree of credibility. When purchasing, pay attention to whether there is a QS logo, factory name, address, grade, etc. on the product label. Production date, shelf life, etc.

2. When purchasing barreled oil, first check whether there are oil stains on the mouth of the barrel. If there is any oil stain, it indicates that the sealing is not tight, which will cause the oil to be oxidized during storage. It also depends on whether there is any sedimentation at the bottom of the barrel. Oil with low processing accuracy will inevitably have sedimentation to varying degrees after being left for a period of time.

3. Look at the production date and shelf life. If the shelf life is greater than one year, antioxidants are generally added. In addition, it is best not to buy oil that has expired within one or two months of its shelf life, because the actual quality of oil that has been exposed to sunlight for a long time has dropped a lot within the shelf life.

4. Color. Good quality corn oil has a light yellow color and a transparent and bright texture. For example, when tested with a Novimin colorimeter, the combination of no deeper than 35 units of yellow and 3.5 units of red is of the best quality.

5. Moisture. If the oil color is transparent and clear, the quality is the best. On the contrary, the quality is poor and the moisture content does not exceed 0.2%.

6. Smell. The ones with corn aroma and no other peculiar smell are of the best quality. Those with a rancid smell are of the worst quality.

7. Impurities. Oil with clear and bright color, no suspended solids and impurities below 0.1% has the best quality.