Why dried legumes take so long to cook

Dried legumes such as kabuli chana (chickpeas), rajma (kidney beans) and kala chana (black chickpeas) are seeds dried to a low moisture content so they keep for a long time. To make them tender, that water has to go back in, and the starches and proteins have to cook through.

Soaking

Home cooks usually soak whole legumes in plenty of water for several hours or overnight (often 8–12 hours for chickpeas and kidney beans). Soaking rehydrates the seed, shortens cooking time and helps the beans cook evenly. Soaked beans are drained and rinsed before cooking.

Cooking

Even after soaking, whole legumes need a long simmer or a pressure cooker to soften fully. The exact time depends on the variety, age and size of the beans.

Raw kidney beans need a proper boil

Raw or undercooked red kidney beans contain a natural lectin, phytohaemagglutinin, which can cause stomach upset. Food-safety agencies such as the UK Food Standards Agency advise soaking dried kidney beans and then boiling them vigorously for at least 10 minutes before simmering until fully cooked. Slow cookers alone may not get hot enough.

Where pre-cooked legumes fit

Pre-cooked legumes have already been soaked and cooked before packing, so the soaking and boiling steps are done for you. Freshcon describes its range as “pre-cooked & do not require overnight soaking, boiling or pressure cooking”: you add your tadka, gravy or dressing and cook for a few minutes.

See Kabuli Chana, Rajma and Kala Chana.

General explainer. Statements attributed to Freshcon are quoted from its own published pages.