Cast iron pot is the most popular traditional cooking pot in China due to its high strength, iron replenishment, economy and practicality. However, the cast iron pots currently on the market are all cast iron or recycled steel. The main components of cast iron: carbon (C) = 2.0 to 4.5%, silicon (Si) = 1.0 to 3.0%. Although it has the advantages of low cost, good castability and cutting performance, and high surface hardness, it is made from pig iron Or it is directly cast from recycled steel. In addition to higher silicon and carbon content, it also contains phosphorus, sulfur, lead, cadmium, arsenic and other harmful elements to the human body. So in the cooking process, although the iron pot can supplement iron, it is easy to precipitate these harmful elements while supplementing iron, especially the heavy metals such as lead, cadmium and arsenic will enter the human body together with food and accumulate over time. It will cause serious harm to the human body. For example, the National Standard of the People’s Republic of China “Hygienic Standard for Stainless Steel Tableware Containers” GB9684-88 has made quantitative regulations on the physical and chemical indexes of austenitic stainless steel and martensitic stainless steel. However, due to the lack of national or industry standards for the sanitary indicators of iron cookware, and the limitations of its manufacturing methods, all manufacturers have not controlled their sanitary indicators. After random inspections, the sanitation of iron cookware, especially cast iron cookware, on the market Most of them do not meet the physical and chemical indicators of stainless steel.
There are also some iron pans stamped from steel plates on the market, although the content of harmful heavy metals can be limited by the choice of steel plate materials, so as not to cause typhoid fever to the human body. However, the carbon content of the steel plate is generally less than 1.0%, resulting in low surface hardness and easy rust. The patent application number 90224166.4 proposes to coat high-strength enamel on the outer surface of ordinary iron pans; the patent application numbers 87100220 and 89200759.1 use the method of coating aluminum on the outer surface of the iron pan to solve the surface rust problem, but these methods isolate the iron The ingredients are in direct contact with the food, and the advantage of iron dissolution in the iron pan is lost.
In addition, iron cookware made by stamping and forming of steel plate has a denser material structure, so its energy storage characteristics and heat preservation are worse than cast iron cookware; and because there are no micropores on the surface, its surface oil absorption and storage performance is also better than that of cast iron cookware. Poor cast iron cookware. Finally, iron cookware made by stamping and forming of steel plate cannot achieve the cooking effect of cast iron cookware because it is difficult to achieve unequal thickness shapes with thick bottom and thin edges in its section.
Post time: Oct-22-2020