Should beans be blanched or steamed for freezing

It is recommended to blanch the beans before freezing. Blanching water can better maintain the taste and nutrition of green beans, mainly due to its advantages such as sterilization and enzyme killing, stable color, flexible texture, nutrient retention, and safe storage.

Blanching can effectively kill microorganisms and oxidases on the surface of soybean beans, avoiding browning and nutrient loss caused by enzyme activity during freezing. Add a small amount of salt or cooking oil to boiling water, blanch for 1-2 minutes until the beans turn bright green, then immediately supercool to lock in chlorophyll and maintain a crispy and tender taste. After blanching, the cell wall of the beans softens more evenly, and it is less likely to become soft or rough after thawing. The loss of vitamin C and B vitamins is also less than that of direct steaming. Although steaming treatment can reduce the loss of water-soluble nutrients, the penetration power of high-temperature steam is weak, making it difficult to completely destroy the oxidase activity in the beans. After freezing, it is prone to yellowing in color and hardening in texture. Long steaming time can also cause the beans to soften excessively, resulting in a soft and chewy taste after thawing. If steaming is chosen, the time should be controlled within 5 minutes and quickly cooled to slow down the damage of residual heat to nutrients. Regardless of the pre-treatment method used, the frozen beans should be thoroughly drained of water before freezing, and the air inside the bag should be expelled during packaging to avoid ice crystals damaging the cell structure. It is recommended to use green beans for stewing or stir frying. After thawing, they should not be cooked at high temperatures for a long time. Carrots, fungus and other ingredients can be paired with daily diet to enrich the intake of dietary fiber and minerals, but it is necessary to pay attention to thorough heating to ensure food safety.