Vacuum frying is a new food processing technology developed in the late 1960s and early 1970s. It has many unique features and widely adaptable to processing materials. Vacuum frying system therefore can be quickly promoted. Vacuum fried foods include fruit, such as apples, kiwis, persimmons, strawberries, grapes, bananas, etc.; vegetable, such as carrots, pumpkins, tomatoes, green beans, sweet potatoes, potatoes, garlic, green peppers, onions Etc.; Meat and aquatic product, such as beef, fish fillets, shrimp, etc. In recent years, China has also been active in research and development of vacuum frying technology. It has already developed vacuum fried products of fruits and vegetables such as bananas and apples.
The vacuum frying technology organically combines frying and dehydrating. The food is under negative pressure and its absolute pressure is lower than atmospheric pressure. In this case of relative hypoxia, food processing can reduce or even avoid oxidation. (eg fatty acid loss, enzymatic browning and other oxidative deterioration, etc.). In a vacuum frying system with a vacuum of 700 mmHg, the boiling point of water can be calculated by the Clausius-Crapperon equation. The boiling point is about 40℃. In the negative pressure state, oil is used as the heat transfer medium. The moisture inside the food (free water and partially bound water) will evaporate rapidly. It causes the structure of loose porous. However, the internal moisture of the food is also affected by factors such as binding force, electrolyte, tissue texture, thermal resistance, and vacuum change. The evaporation of water is much more complicated. The specific production conditions should also be combined with the temperature conditions required for enzyme elimination.
A new generation of advanced vacuum fryer equipment developed by Qingdao Liuyi Machinery is used in various series of natural foods: fruit and vegetable chips series, dried fruit series, aquatic products, livestock and poultry meat series. We believe that our fryers can be developed more series. Because of the great features of vacuum fried foods, they will be more and more popular among consumers. Thus it can replaced traditional fried foods and become the new favorite snacks in the food market.