91色情片

What you need

Beans

Tahini

Garlic

Lemon juice Chilli flakes

Salt

Water

Red onion

Olive oil

Parsley

IF YOU are taking part in Veganuary or just cutting down on meat, beans are a valuable source of protein for anyone on a plant-based diet. They owe their high protein content to a symbiosis with Rhizobium bacteria, which the plants foster inside nodules in their roots. These bacteria can absorb nitrogen from the air and convert it into ammonia, which the plants can use to make protein-building amino acids.

Beans, peas and lentils 鈥� and peanuts 鈥� are the seeds of legume plants. They have a tough coat made up mostly of cell-wall carbohydrates. Inside the seed are two embryonic leaves called cotyledons, which store starch and protein to nourish a seedling. Some beans, such as kidney beans, contain phytohaemagglutinin, a toxin that causes red blood cells to clump, but it is destroyed with proper cooking.

Tinned beans are convenient, but their flavour is a poor relation to that of dried beans cooked at home. You can cook them without pre-soaking, but they cook more quickly and evenly after being soaked for at least 12 hours. The low permeability of the seed coat means they absorb water slowly, letting it in initially through the hilum or 鈥渆ye鈥� of a bean. After 12 hours, beans have typically doubled in weight.

Once a bean is hydrated, its gelatinisation of starch and solubilisation of pectin.

In the seed coat and the cotyledons, cells are held together tightly by pectin molecules, with calcium ions forming strong cross links between the pectin. The pectin molecules must break apart and dissolve for the beans to soften.

Hard water with a lot of calcium or magnesium in can reinforce the bean cell walls, increasing the time needed to cook them. Many people say you shouldn鈥檛 add salt when you soak and cook beans, but I found that beans soaked and cooked in salted (2 teaspoons per litre) water softened faster and tasted better than beans soaked in unsalted water. The sodium ions may weaken the bonds between pectin molecules.

You can cut the cooking time further by adding a teaspoon of bicarbonate of soda per litre to the salted water. This makes the water alkaline, helping to weaken pectin as well as unfolding proteins.

Acids, on the other hand, inhibit softening, which is why beans can be simmered for hours in tomato sauce without falling apart. It is best to cook beans alone before adding them to soups if you aren鈥檛 planning a lengthy cooking time.

The Turkish salad piyaz (pictured) is a delicious way to enjoy any bean. Mix tahini, garlic, lemon juice, chilli flakes and salt, adding water to make a smooth sauce. Use this to dress cold, cooked beans along with finely chopped red onion. Drizzle with olive oil and scatter over some parsley.

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