How to stir-fry beans without changing color? Tips for cooking vegetables without discoloration

Cut lotus root slices, potatoes or yams turn brown in a blink of an eye. This is due to their rich phenoloxidase enzyme. This can be solved by scalding them in boiling water for 10 seconds, which not only "kills" the enzymes, but does not affect the taste. Or cut it and soak it in water, drain it and quickly put it into the pot before cooking.

How to stir-fry beans without changing color? Tips for cooking vegetables without discoloration

Tips for cooking vegetables without discoloration

Rhizomes.

Cut lotus root slices, potatoes or yams turn brown in a blink of an eye. This is due to their rich phenoloxidase enzyme. This can be solved by scalding them in boiling water for 10 seconds, which not only "kills" the enzymes, but does not affect the taste. Or cut it and soak it in water, drain it and quickly put it into the pot before cooking. If you want to make the enzyme more "honest", you can soak it in salt water, which can inhibit the enzyme and reduce the amount of dissolved oxygen in the water. In addition, adding acid to the water is also a good idea. Adding some lemon juice can not only inhibit enzymes, but the rich vitamin C can also restore the oxidized parts, making the color whiter.

Leafy vegetables.

Green leafy vegetables are the easiest to change color because they are rich in chlorophyll. Chlorophyll is very fragile. It is afraid of light, heat, acid and oxygen. Keeping it stable is a big problem. To prevent green leafy vegetables from changing color, process them before adding them to the pot. Soak the cut vegetables in cold water to isolate them from oxygen in the air. The most important thing is to shorten the cooking time. Generally speaking, stir-frying over high heat, quickly blanching, then immersing in cold water, cooling thoroughly and then frying can keep the green color well. In addition, do not cover the pot when frying green vegetables to prevent the organic acids in the vegetables from evaporating, forming an acidic environment and causing the chlorophyll to decompose. At the same time, do not add vinegar and other sour foods as ingredients.

Green vegetables tend to turn brown, while purple vegetables, such as purple cabbage, tend to turn blue when cooked. The natural anthocyanins in purple cabbage are blue-purple under neutral conditions, and turn blue under alkaline conditions. Therefore, the processing method should be exactly opposite to that of green vegetables. It is necessary to create acidic conditions. Covering the pot will help maintain the color. Adding a little vinegar will make the purple cabbage more red.

onion.

Many people are "at a loss" when it comes to onions. If they fry them in an iron pan, they will change color, and if they fry them in an aluminum pan, they will change color. This is because onions contain a substance called flavonoids. When flavonoids meet iron, aluminum and other metals, they will generate brown, blue, black and other compounds, making the color of onions opaque. The best solution is to dip the cut onions in some dry flour and mix well before frying. This can prevent the flavonoids from coming into direct contact with iron and aluminum, and the onions will not change color and the taste will be crisper and tender.

Legumes.

Beans such as kidney beans and broad beans are also more likely to change color when added to dishes, so they can be "oiled" in advance. Stir-frying or sautéing the beans with oil before frying can maintain the emerald green color of the beans better than blanching them with water. Because the oil has a high temperature and a certain viscosity, a dense oil film can be formed on the surface of the beans, which reduces the oxidative discoloration and loss of green substances.