There are many varieties of beans, which are nutritious, but eating too many can easily cause gas. In fact, the problem of gas can be improved by pre-treating the beans before cooking.
Soybeans contain 25%-30% carbohydrates, which are complex and consist mainly of cellulose and soluble sugars. Only half of these are digestible, while the other half are the gas-producing factors, raffinose and stachyose. Bacteria in the large intestine break down these sugars, producing acids and gases, which is beneficial for gut health but also leads to the production of carbon dioxide, hydrogen, and small amounts of methane, causing bloating, rumbling, and other symptoms.
In addition to soybeans, raffinose and stachyose are also present in other legumes such as lentils, peas, fava beans, mung beans, and peanuts. Research has shown that these gas-producing factors are heat-resistant but water-soluble. Soaking, steaming, or sprouting soybeans can significantly reduce their content.
Therefore, soaking beans for about an hour before cooking and then discarding the water can reduce their gas-producing effect. For people who are prone to gas, it's important to gradually increase the frequency and amount of beans consumed, not eating too much at once, so that the body can gradually adapt.
For those with weaker digestive systems, it may be better to opt for bean sprouts or processed bean products. During the sprouting process, beans break down these two substances. In the processing of bean products, the gas-producing factors dissolve in water and are mostly removed.