Why do green vegetables are treated with blanching before processing?

Green vegetables are blanched with hot water of 60-75 °C before processing , so that the chlorophyll hydrolase loses its activity, and it can maintain its bright green color. When the heating temperature reaches the boiling point of chlorophyll, chlorophyll is easily oxidized, after scalding hot water 60-75 deg.] C, may be excluded vegetable tissue of oxygen, even when high-temperature treatment, since the chances of oxidation is reduced, it is still Keep it bright green. In addition, after the vegetable is blanched , a considerable amount of acid in the green vegetable tissue can be reduced , and when it is treated at a high temperature, the action of chlorophyll and acid can be reduced, so that pheophytin is not easily formed. In addition, chlorophyll hydrolase activity is strong at 60-75 °C, which can hydrolyze chlorophyll into a stable green methyl chlorophyll acid.  

For water used for blanching vegetables, it is best to use a pH of 6 . 5-7 . 0 or slightly higher, so that vegetables are easier to preserve the original bright green. The temperature and time of blanching are different for different vegetables. If the temperature is too high and the time is too long, the green color easily disappears or pheophytin is formed. Green vegetables are treated with lime water or magnesium hydroxide to increase the pH before processing , which can reduce the formation of pheophytin and maintain the color of vegetables. However, when too much alkali is used, the texture and flavor of the plant can be impaired. In addition, chlorophyll is also relatively stable in its low temperature or dry state. Therefore, vegetables stored at low temperatures and dehydrated and dried vegetables can maintain their bright green color.

The blanching machine manufactured by Zhucheng Jianfeng Machinery Co., Ltd. has the characteristics of rapid killing, inhibition of enzyme color protection and timely dehydration and cooling, and the characteristics of one-time completion, so that fruits and vegetables maintain the original natural color. Through this machine, the activity of enzymes in fruits and vegetables is stopped, in order to maintain the unique vivid color of fruits and vegetables, to distribute the green odor of vegetables and to retain the aroma, to enhance the softness of cells, and to facilitate the evaporation of water, which is the process of drying and dehydrating the next process. A good foundation is required.