The color of new soybeans is light yellow.

The color of old soybeans is light yellow.

Step 2 look at your head

Fresh soybeans are bigger and full of grains.

Old soybeans are small and shriveled.

3. Look at the soaking time.

New soybeans only need to be soaked for 12 hours, and only a small part can't be soaked.

Old soybeans can't soak for 15 hours, but they will swell.