The processing of dehydrated vegetable rong generally needs to go through the following steps: ①Select raw materials, remove unqualified raw materials such as mildew and spoilage, diseases and insect pests, insufficient maturity and excessive maturity, and remove impurities. ②Clean, wash with clean water to remove the dirt, silt and microorganisms on the surface of the vegetables. For vegetables sprayed with pesticides, wash them with a hydrochloric acid solution with a concentration of 0.5 to 1.0%. ③Peeling different kinds of vegetables has different peeling methods and requirements, such as bamboo shoots and green beans-usually by hand or mechanical peeling (or removing English), tomatoes are usually peeled with steam or hot water, and carrots are peeled with concentrated lye. ④ Divide. ⑤ Blanching, that is, the cut (or uncut) vegetables are heated in boiling water or atmospheric steam for 5 to 8 minutes to destroy the enzyme activity and kill the eggs and some microorganisms attached to the surface of the vegetables. After blanching, quickly cool with cold water. ⑥ Sulfur treatment Soaking vegetables in a solution of sulfurous acid and its salts is a necessary pretreatment for many vegetables before drying. Such as bamboo shoots, needles vegetables, cabbage and Maling Lane must be treated with sulfur after being cut and blanched, usually soaked in sodium bisulfite solution with a concentration of 0.1 ~ 0.2%. Beans and green peas do not require sulfur treatment before being dried. ⑦Drying is carried out in drying equipment. Commonly used drying equipment is a tunnel dryer. ⑧ Homogeneous vegetables are piled up or placed in a closed container immediately after drying, picking, and cooling to balance their moisture. ⑨Package, use polyethylene or polypropylene plastic bag.
Fresh vegetables have a high water content, mostly above 90%, of which free water accounts for the majority, so they are prone to microbial infections. In addition, fresh vegetables are large in size and fragile, which brings certain difficulties to storage and transportation. The dehydrated vegetable processed products have low water content and can effectively inhibit the activity of microorganisms and the activity of enzymes in the tissues. Therefore, the storage period is prolonged, the volume is reduced, the weight is reduced, and the storage and transportation are convenient.