Pulse fiction: Swetha Sivakumar on dal as a toor de force

I am fascinated by dals. Maybe by the end of this piece, you will be too.

PREMIUM

This week, let’s talk a bit about my big four: toor, moong, urad and chana. First off, none of these is a lentil. Lentils, in their unhulled state, must have a double-convex shape (the word has the same Latin root, in fact, as “lens”).

Masoor is a lentil; Beluga lentils are too (so named because they look just like black caviar).

None of the big four has a double-convex shape. They can, instead, be called legumes (the term for the entire plant) or, more accurately, pulses (the term for the seed). In their hulled, split versions, though, these pulses look and behave very much like lentils, and that’s why they are so often mis-tagged.

So that’s what separates a pulse from a lentil. What really fascinates me is what separates pulses from grains.

Grains (and cereals) come from the grass family Poaceae; pulses, from the family Fabaceae or Leguminosae. They are both seeds that carry an embryo, along with the lunchbox the mother plant packed for that embryo.

Look closer and one sees that the lunchboxes are quite different. Pulses, on average, contain far less starch and two to three times more protein than grains do. They also contain more fibre. While this makes them a much healthier ingredient, it also means they must be cooked much longer before we can eat them. Here’s why.

Starch, the most prevalent ingredient in grains, gelatinises at about 68 to 78 degrees Celsius. So one can easily cook white rice on a stovetop. Pectin, which makes up 15% to 30% of the fibre in pulses, start dissolving only around 88 degrees Celsius, which means one must either use a pressure cooker or keep the pot on the boil in order for the dal to soften.

The differences extend to their texture after cooking. Cooked dal is often whisked while hot. The seeds, swollen with water, respond to the force of the whisking by bursting wide open, spilling their contents into the liquid, and absorbing the flavours of all the ingredients in the pot as a result.

One could whisk grains when cooked and liquidy too, but the resultant soup would be so rich in starch that it would have a milky appearance and would congeal as it cooled.

Now, not all pulses react in exactly the same way to heat, because they vary widely in protein, fibre and carbohydrate content. That’s part of what makes the big four so interesting to me.

In traditional Indian recipes, we can still see how our ancestors recognised different pulses’ characteristics and began to capitalise on them, centuries ago. Take toor dal, for instance. It is the seed of the pigeon pea, a drought-resistant crop with very deep tap roots. In Malawi, the largest producer of this pulse in Africa, it is called “desperation food” and 90% is exported (with a major buyer being India); because the local cuisine there does not include recipes that make it palatable.

Perhaps, traditionally, the region did not have the plentiful water required to treat it correctly; and toor must be treated exactly right, if one is to enjoy it.

The pigeon pea seed coat is extremely tough, even when compared with other pulses. The coat is bound firmly to the cotyledons within by gums and mucilage. In traditional south Indian recipes, toor dal is soaked in water, coated with red earth, and sun-dried, to loosen the coat; then dehulled using a manual grinder. This reduced cooking time considerably, which was vital because fuel was scarce and labour-intensive to gather. The prize that toor offers in exchange for all the time and effort is a bounty of protein. That is one reason it is so highly prized in India.

If toor is a well-concealed treasure, moong is a nostalgia ride; chana is designed to be versatile; and urad has a secret superpower. But more on these three next week. See you then.

(To reach Swetha Sivakumar with questions or feedback, email [email protected])