Beans still tough

Why they will not soften

In order of likelihood.

• They are old. Dried beans deteriorate on the shelf. After a couple of years the cell walls change and some beans simply will not soften however long they cook. There is no fix, and the packet rarely says when they were dried.
• Acid in the pot. Tomatoes, vinegar, wine and lemon all slow softening dramatically. Add them once the beans are already tender.
• Hard water. Calcium and magnesium strengthen the cell walls. A pinch of bicarbonate of soda counteracts it.
• Not enough water, or not simmered. Beans need to stay submerged and to be genuinely simmering, not held below it.
• Not soaked, and not given the extra time. Soaking is not compulsory and it shortens cooking substantially.
• Cooked with sugar or molasses from the start, which also slows softening — the reason traditional baked beans take so long.

The salt argument, resolved

The old advice was never to salt beans until they were tender, because salt was said to toughen the skins. That has been tested repeatedly and the opposite appears to be true.

Salt in the soaking water and the cooking water helps: the sodium displaces some of the calcium and magnesium in the cell walls, which makes them soften more readily rather than less. Salted beans generally cook faster and hold their shape better.

What genuinely does slow them down is acid and sugar. That is what the old advice was probably reacting to, in pots that contained tomato or molasses along with the salt.

Cooking them so they soften

1. Buy from somewhere with turnover, and use them within a year. This matters more than anything else on this page.
2. Soak overnight in plenty of salted water, or use a quick soak — boil for a minute, cover, and stand for an hour.
3. Drain the soaking water and cook in fresh salted water.
4. Cover generously. Beans absorb a great deal and must stay submerged.
5. Simmer gently. A hard boil breaks the skins and gives mushy outsides with hard centres.
6. Add nothing acidic or sweet until the beans are already tender. Tomatoes, vinegar and sugar all go in at the end.
7. If your water is hard, add a small pinch of bicarbonate of soda. Too much makes them slimy and soapy.
8. Test several beans, not one. They cook unevenly.

When to give up

Three hours and still hard

Almost certainly old beans. More time will not help.

Some soft, some hard

Uneven age or size in the packet. Common and normal.

Skins split, centres hard

Boiled too hard, or bicarbonate overdone.

Soft then went hard again

Acid was added while they were still finishing.

Salvage

Blend them into a soup, a dip or a purée where the texture is no longer the point.

Tinned beans

Already cooked and consistent. No shame in them at all.

Common questions