To reduce the loss of water-soluble vitamins during blanching, the following points should be noted:
1. Use boiling water and keep the time short. Add the vegetables to the water after it has come to a boil. This short blanching process in boiling water reduces thermal loss of nutrients. Additionally, boiling water contains almost no oxygen, which minimizes the loss of Vitamin C due to oxidation.
2. Do not cut the vegetables before blanching. Before blanching, vegetables should be kept as whole as possible to reduce the surface area exposed to heat and water. If you have a large quantity of vegetables, blanch them in batches to ensure they remain in the high-temperature water.
3. Cool the vegetables immediately after blanching. After blanching, vegetables are hot and will be exposed to oxygen in the air upon removal from the water, which can easily lead to nutrient loss. Therefore, blanched vegetables should be promptly submerged in a large amount of cold water to isolate them from oxygen and cool them down, thereby reducing nutrient loss.