Soil pressing is not as safe as refining! Uncover several major questions about rapeseed oil

　　Rapeseed oil is a traditional edible oil in many parts of China, but there are many questions about it.

　　Why does rapeseed oil have a "strange smell"? The unique "aroma" of various vegetable oils comes from the volatile components in it. In the case of rapeseed oil, it is mainly glucosinolates. Glucosinolates, also known as glucosinolates or glucosinolates, decompose to produce isothiocyanates, nitriles, cyanates and other substances. Many sulfur-containing compounds have a certain degree of irritation, which also produces a unique flavor.

　　How is the nutritional value? Like other vegetable oils, rapeseed oil has a relatively low saturated fat content, which is healthier than animal fats. But ordinary rapeseed oil contains erucic acid. Animal experiments have shown that erucic acid is harmful to the heart. In addition, isothiocyanate, the breakdown product of thiosinolates, can interfere with thyroxine synthesis and cause thyroid enlargement. Nitrile can also cause liver and kidney enlargement in animals, and in severe cases, it can cause liver bleeding and liver necrosis. Although as edible oils, the amount of consumption is generally not large, and the harm caused is not necessarily much. But they are "harmful ingredients" after all, so from a health perspective, ordinary rapeseed oil is obviously not as good as other vegetable oils.

　　Is it true that rapeseed oil causes Alzheimer’s disease? The claim comes from an animal experiment using mice with a genetic mutation that predisposes them to Alzheimer’s disease. In the experiment, the experimental group and the control group ate different diets. The experimental group of mice increased rapeseed oil, which increased calorie intake and caused obesity. From a scientific point of view, the study is not convincing and has been criticized by many professionals.

　　Is soil oil better? Many people believe that soil oil "untreated by modern industrial means" is more "healthy" and more "safe". This is not the case. Soil oil contains free fatty acids, pigments, and volatile components, which make the oil smoke at relatively low temperatures. Soot is not only a source of PM2.5, but also contains harmful substances such as acrylic. Acrylic has a strong irritating effect on the eyes and respiratory tract, and was even used as a chemical weapon in the "First World War". When "soil pressing" is applied to high temperature treatment of rapeseed, it will produce carcinogenic benzopyrene. In addition, smoke also produces other harmful substances. Commercial oils are generally refined to remove free fatty acids, pigments, and odors from the oil. Refined oils are light in color, have a bland taste, and have a bright appearance. The smoking temperature can increase by 50 or 60 degrees Celsius. From a safety point of view, "home-squeezed oil" is not as good as refined oil. Of course, vegetable oils also lose some health benefits during the refining process, such as vitamin E and phytosterols. From this point of view, soil-squeezed oils have certain advantages over refined oils.

　　What should be paid attention to when choosing rapeseed oil? Soil-squeezed oil has certain advantages over refined oil in nutrition, but for food, we should consider nutrition under the premise of safety. The nutrients lost by refined oil can be obtained from other foods, while the harm caused by oil smoke and benzopyrene cannot be eliminated. Therefore, refined oil is a better choice. More importantly, the glucosinolates and erucic acid in traditional rapeseed oil are not good for health, and the improved "double-low rapeseed oil" solves the above problems. "Double-low rapeseed oil" is also called "canola oil" and "canola oil". Its fatty acid composition is reasonable, high quality and low price, and it is a healthy and cheap choice. ▲