The role of blanching machines in fruit and vegetable processing

During the processing of fruits and vegetables, we need to use a hot water fruit and vegetable blancher to prevent discoloration (such as Browning), flavor deterioration and nutrient loss (such as vitamin C degradation) caused by enzymatic reactions during processing or storage. For instance, the inactivation of peroxidase and oxidase can protect the stability of chlorophyll and carotenoids. ‌

The Ruite continuous hot water blanching machine inactivates enzymes through short-term heat treatment (usually 80-100 °C), extending the shelf life and maintaining sensory quality. At the same time, it removes some unpleasant odors such as pungent and astringent flavors, and stabilizes the color (for example, green leafy vegetables become brighter after blanching). Reduce surface contaminants, bacteria and insect eggs to enhance food safety. Soften the cell wall, enhance elasticity, increase cell permeability, facilitate rehydration after dehydration and drying, and facilitate subsequent processing (such as canning and dehydration).

The raw materials for fruit and vegetable products can be used at a relatively low temperature. For instance, spinach and scallions used to make dehydrated vegetables can only be blanched at around 70℃ for a few seconds or minutes; otherwise, their sensory and tissue conditions will be severely affected. Some green vegetables often add alkaline substances such as baking soda and calcium hydroxide to the blanching solution to maintain their green color. However, such substances have a significant impact on the loss of vitamin C. Sulfites are sometimes added to preserve vitamin C,. In addition, some fruits and vegetables used in canned food can also be blanched with 2% salt water or 0.1% to 0.2% lemon acid solution.

The advantages of hot water blanching are that the materials are heated evenly, the temperature rises quickly, the use method is simple and the processing output is large (up to 3-5 tons per hour). The running speed and blanching temperature can both be set according to different products and processes, so it can also be applied to a variety of fruit and vegetable products. It is mainly applied to the blanching treatment of products such as potatoes, lotus roots, bamboo shoots, lettuces, cauliflowers, cabbages, konjac, mushrooms and corn. Meanwhile, this equipment can also be used for the pasteurization treatment of bagged fruit and vegetable products, bean products, meat products, and seafood. It is one of the essential and efficient devices in the food processing industry.