If the blanching time is too short it will leave the cowpeas with a pea-like odor and a hard texture.
If the blanching time is too long, the cowpeas will become soft and lose their crispness and yellow color.
Raw cowpeas contain "lectins" and "saponins" which are harmful to human body, these two toxins can be broken down and destroyed in high temperature, and if you eat half-raw cowpeas, it will cause food poisoning.