How to dehydrate vegetables

summary

Fruits and vegetables can be stored for a long time and keep their original shape, color, taste and nutrients. They are easy to eat. At the same time, due to their low water content and easy transportation, they can effectively regulate the production of fruits and vegetables in low and peak seasons. Next, I'd like to share with you some knowledge about how to dehydrate vegetables.

How to dehydrate vegetables

First, there are two kinds of dehydration methods: natural drying and artificial dehydration. Artificial dehydration includes hot air drying, microwave drying, infrared and far infrared drying, freeze vacuum drying and so on. At present, hot air drying is widely used in fruit and vegetable dehydration.

Second: the main varieties of dried fruit are raisins, red dates, persimmons, dried litchi, dried apricots, dried pears, dried apples, dried peaches, etc. The main varieties of dehydrated vegetables are onion, radish, carrot, potato, day lily, pepper, beans, tomato, cabbage, wild vegetables, edible fungi and ginger.

Thirdly, the drying mechanism of fruits and vegetables with atmospheric hot air technology is the same as that of other conventional materials, that is, under atmospheric pressure, hot air is used as the drying medium to make the internal water of fruits and vegetables diffuse to the surface (internal diffusion) through capillary tube, and then from the surface to the outside (external diffusion), The main feature of this method is that it uses the hot air with reasonable temperature and air volume to promote the internal water diffusion of fruits and vegetables.

matters needing attention

After dehydration, the moisture content of vegetables is reduced to 4% ～ 13%, and the water activity is reduced to about 017, which makes microorganisms and enzymes inactive. The products can be stored for 2 ～ 3 years in sealed or vacuum packaging. Compared with fresh raw materials, the quality of the products is reduced by 10 ～ 20 times. The products can be re fresh in 3 ～ 10 minutes, and the re freshness ratio is 1 ∶ 3.5 ～ 10.5, and the re freshness is more than 90%. In addition, the dehydration of vegetables results in the environmental conditions that are not suitable for the growth of microorganisms, and prevents the growth and reproduction of microorganisms, especially pathogenic bacteria, so as to achieve the effect of antisepsis and preservation.