If the lettuce is only a little red, first, it is caused by the aging of lettuce; Second, the red phenomenon caused by the oxidation of cut lettuce in the air; Third, lettuce is sick, similar to the phenomenon of sugarcane hearts. As long as the lettuce is not rotten, the whole lettuce can be safely eaten, but the taste is not fresh and the nutritional value is somewhat reduced.

Can lettuce be eaten when it turns yellow? You can also eat it, and it won't rot.

Under normal circumstances, the meat quality of lettuce is green, but if it turns yellow, it may be caused by long-term aging of lettuce; Second, the lettuce was exposed to the air for too long, and the polyphenols reacted with oxygen and turned yellow, showing red and black. In both cases, yellow lettuce can be eaten if there is no soft rot and odor, but the taste and nutrition will be greatly reduced.

3 How to avoid lettuce oxidation 1, soaking method to avoid lettuce oxidation yellow, red and black, you can learn from the usual method of processing shredded potatoes and soak the cut lettuce in water, but this storage method can not be preserved for a long time, and the soaked lettuce should not be eaten for more than 4 hours to avoid lettuce breeding bacteria and bad taste.

2. blanching and cold storage method you can also blanch the cut lettuce with boiling water, then take it out and drain it, put it in a sealed fresh-keeping bowl, and then put it in the refrigerator for preservation. In this way, lettuce will not be oxidized, and it can be kept fresh for 1-2 days.

4 How to choose lettuce 1? Good fresh lettuce should be straight, symmetrical, without rotten leaves, damage, soft rot and thin cross-sectional incision. And bad lettuce may be dark in color, yellow in leaves and rotten in leaves. Remember to look at the roots of lettuce. If the root is completely transparent, it means that it is tender inside. If there is a white spot or even a hole in the middle, it is old.

2. Remember a trick when choosing fresh fruits and vegetables, that is, in the case of the same size, you must choose a heavier one, so that the food has more water, while the lighter ones are mostly left for a long time or rotten and hollow.

3. Smelling high-quality lettuce will have its special green vegetable fragrance, while bad lettuce smells either rotten or strange, which is mostly a manifestation of lettuce rot.