If the soaked bean sprouts have gray spots, it may be because the bean sprouts have been soaked in water for a long time, resulting in poor water quality or large impurities in machinery or equipment, or the bean sprouts themselves are not well preserved.

Soaking in water for a long time will make bean sprouts moldy and produce gray spots, which will affect the taste and health. Therefore, it is suggested that the soaking time of bean sprouts should not be too long, 15~30 minutes, and the water source with good quality should be selected for soaking.

If bean sprouts are not well preserved, they are also prone to mildew and spots. It is recommended to buy fresh and dry bean sprouts, keep them ventilated, moist and out of direct sunlight, and avoid excessive humidity and mildew.

If bean sprouts are moldy and have gray spots, it is best to discard them and not eat them, so as not to affect your health.