Normal temperature dewatering method for vegetable and fruit

Abstract

The invention provides a method for dehydrating vegetables and fruits at normal temperature, which comprises: a step 1 of dehydrating vegetables and fruits with purified air; a step 2 of dehydrating the raw material obtained from the step 1 at high pressure, evacuating a dehydrating pot till the pressure is 0.08 to 0.09MPa, adding nitrogen or carbon dioxide gas into the pot, keeping the pressure for a preset time and reducing the pressure to normal pressure; and a step 3 of dehydrating the material obtained from the step 2 in a drying bin till the water content is less than 5 percent. The method adopts different dehydration means according to the different states of the water in the raw material, has the advantages of low equipment investment, low operation cost, easily controlled technique, wide processing range and the like, enables the dehydrated vegetables and fruits to replace kiln dried and freeze dried products and enlarges the sales market of the vegetables and fruits. The product of the method has the same quality as freeze dried products and creates larger profit margin than the freeze dried products, even when sold at a price which is only 60 to 80 percent of that of the freeze dried products.

Description

technical field [0001] The invention relates to a method for dehydrating food to make it easier to preserve, in particular to a method for dehydrating vegetables and fruits at normal temperature. Background technique [0002] The dry production technology of fruit and vegetable foods is an important field in the food processing industry. Dehydrated fruits, vegetables, and edible fungi have a long shelf life, are convenient to transport and eat, and are bulk products in domestic and foreign markets. However, due to the use of high temperature and deep-frying methods, the conventional drying process destroys the nutrients of the food, loses vitamins, deteriorates the color and flavor, and even produces carcinogens, which is not suitable for people's health. Therefore, some high-temperature dried and fried foods have to withdraw from the market. With the improvement of people's living standards and the enhancement of health awareness, most high-temperature dried and fried food...

AI Technical Summary

Problems solved by technology

The disadvantage is that the equipment investment is large, the production efficiency is low, the processing cost is high, and the energy consumption is high. Therefore, small and medium-sized enterprises are unable to invest in construction, and it is difficult to form large-scale production

Moreover, some fruits are not suitable for freeze-drying processing, for example, winter jujubes are easily broken when they are quick-frozen