Canned cannellini beans
Why Canned Beans Come Out As Foamy After They're Rinsed
When using beans to make dishes like chili or humus, you might have noticed a familiar yet intriguing phenomenon: the bubbly foam that appears when you rinse canned beans in water.
The foam is a mix of proteins, starches, and saponins that are present in beans and infuse any surrounding liquid. When agitated, these elements whip into a foamy lather.
Saponins, in particular, have soap-like foaming qualities and appear in many other foods. They are perfectly safe to consume, with some studies even claiming health benefits.
Rinsing canned beans is recommended because it reduces sodium content and prevents dishes tasting too salty. Skipping this step may also lead to a bitter flavor from the foam.