You can press a good squeeze peanut oil, peanut oil into the refrigerator freezer for about 10 minutes , if the oil solidification phenomena occur , mixed with palm oil can initially identified ; into the refrigerator freezer for about 30 minutes or so , if the oil appears points layer and solidification phenomena , initially identified mixed with canola oil can . Fresh squeezed out of the peanut peanut natural color, bright golden , full-bodied flavor with a natural smell of peanut oil . If using vegetable oil plant the summer, peanuts , peanut oil squeezed out of the darker color . Sniff the odor . With the right hand little finger contaminated with oil , rub in the left hand and shoved a few hearts , and then immediately smell the odor, pure peanut oil with a rich aroma, no abnormal taste , can be considered the top grade. The incorporation of peanut flavor began a slight peanut flavor , but with the rub again , this peanut flavor will be more light. If there is no oil , it will cause vitamin deficiency , and the lack of essential fatty acids , corn mill grinder health. Only emphasizes eating vegetable oil , do not eat animal fat, is not acceptable. Under certain dose , animal oil ( saturated fatty acids ) is beneficial to the human body the actual test . Color press quality peanut oil at room temperature, light yellow, clear and transparent ; smell , taste normal , oil heated to 280 degrees change color depth , no precipitation precipitation ; inferior peanut oil color, smell , taste exception occurs, the water large, impurities, rancidity, there smelling odors smell. Therefore , when the oil is not good cold smoke.