Different Dals used in Indian cooking

How to differentiate various indian pulses/dals ?
When to use which pulse ?

Some of the most common forms of dahl or dal include:

Masoor and Masoor Dal

Masoor dahl - red lentils

If you've ever been in an organic store where they have bulk foods you might have seen bins full of small, flattish round, red or reddish orange legumes. This is a type of dahl called masoor dahl in India.It is brown skinned lentil that is orange on the inside. Masoor dal has a pleasant earthy flavor and is very common in Northern India. It is commonly used to make dal, soups and stews.

Chana dahl - split garbanzos

Channa Dahl:

This is a smaller type of garbanzo than the stuff we find on the grocery store shelves here. It can be very difficult at first to tell the difference between chana dal and Toor dal - they're about the same size and about the same color. However, chana dal is slightly irregular in shape (a little bit lumpy looking of you look closely) and a bit thicker than toor dal. The whole bean is closer to round in shape than whole toor dal (pigeon peas). So if you can compare them side by side, chana is slightly larger, thicker, bumpier. Toor dal is flatter, slightly smaller, more regular in shape.

Toor dahl - split pigeon peas

Note the greater symmetry and more flattish shape of this compared to Chana dahl. 

Mung or moong dal - split mung beans

Mung dal (also called green gram when it is whole) and urad dahl (see below) can also be difficult to differentiate. In general, urad dahl will be chalkier and nearly white, while mung dahl will be more of a creamy yellow. Whole mung is a small oblong bean with a black eye and a green skin. The whole, unhulled mung bean is used to grow the bean sprouts we see in a lot of Chinese dishes.
They are eaten whole, sprouted, split with the skins on and split with the skins removed.

Mung beans with their skins on have a flavor reminiscent of green leafy vegetables but the mung dal with the skins removed has a mild sweet flavor and is often used for desserts.

Urad Dahl

Urad is very similar in appearance to mung dal, urad being whiter compared to creamy yellow for mung. The whole bean is very dark, nearly black, small and oblong. The whole bean is easily differentiated from whole mung.
Urad has an earthy flavor and an unusual mucousy texture (it’s a good thing!) when it’s cooked. The popular, and amazing, dal makhani is made with urad. Papad (or poppadums) are usually made with urad dal as well.

Rajma dal - red kidney beans

Rajma dal is simply whole red kidney beans. Generally the varieties used in India are smaller than some of the varieties you will find on grocery store shelves in the US. If you have a choice when buying kidney beans for use in a recipe calling for rajma dal, buy the smaller size bean when available.

Black Eyed Peas and Azuki beans

 Black-eyed peas have a distinctive flavor and are an all around pulse in Indian cuisine. They’re used to make curries, dals, papads and fritters.Azuki beans have a sweet nutty flavor and are another all around pulse. They are used very much like black-eyed peas.

There are many other types of dal but these are the most common types. Dals are used whole, hulled and split, or ground into flour. Besan, for instance, is ground urad dal. Some dals are wet-ground (you soak them and then grind them in special grinders to make a paste) and then fermented to make dosai (sort of like a crepe) or idli (a steamed rice-dal patty frequently served with sambar).

 Cooking time for various dals and pulses

Bean	Cook Time	Pressure Cooker Time	Whistles	Slow Cooker	Soak
Mung, whole	60 to 70 minutes	8 to 10 minutes	5	low 5 to 6 hours	4 hours (optional)
Mung, split	20 minutes	6 to 7 minutes	3	low 3 to 4 hours	optional
Urad, whole	60 to 70 minutes	10 to 12 minutes	6	low 5 to 6 hours	4 hours (optional)
Urad, split	30 minutes	8 to 9 minutes	4	low 4 to 5 hours	30 minutes (optional)
Garbanzo, white/brown	70 to 90 minutes	20 minutes	8	low 8 to 9 hours	8 hours to overnight
Garbanzo, split (channa dal)	60 to 70 minutes	15 minutes	7	low 7 to 8 hours	optional
Masoor, whole	40 to 45 minutes	7 to 9 minutes	7	low 7 to 8 hours	optional
Pigeon Pea, whole	70 to 90 minutes	15 to 20 minutes	8	low 8 to 9 hours	8 hours to overnight
Pigeon Pea, split (tuver dal)	30 to 40 minutes	7 to 9 minutes	5	low 5 to 6 hours	30 minutes (optional)
Black-eyed Pea/Adzuki, whole	60 to 70 minutes	15 to 20 minutes	6	low 6 to 7 hours	optional
Black-eyed Pea, split	30 to 40 minutes	8 to 9 minutes	4	low 4 to 5 hours	optional
Dry green Pea, whole	60 to 70 minutes	15 to 17 minutes	6	low 6 to 7 hours	8 hours to overnight
Kidney Beans, whole	Boil for 30 minutes then simmer for 30 to 60 more minutes.	12 to 15 minutes	6	Toxic. Do not cook in slow cooker.	8 hours to overnight

Cooking Notes:

• Before you cook the pulses, sift through them to take out any pebbles or debris. Then rinse them a few times.
• Pulses taste best when they are cooked slowly. When cooking pulses on the stove top, bring to a boil and lower heat to medium low and let simmer. Start counting the cooking time once the pot has come to a boil and not before. In the case of kidney beans, boil for 30 minutes before lowering heat to simmer.
• If your pulses are old, they can take double the time to cook. If they haven’t softened in the time indicated, don’t worry. Just cook until soft. Make sure to add more water as needed.
• When cooking pulses, hold off adding salt or acids (such as lemon or vinegar) until the end, or the they will not soften.
• Water: If you are cooking on the stovetop or slow cooker, use about 3 to 4 times the water. In the pressure cooker, two times the water will do. Always keep an eye on the stove and add more water if it starts to look dry.
• Indian pressure cookers are a little different from the ones available in the West. They usually release steam regularly in what is referred to as “whistles.” These whistles are counted to determine cook time. They are not always accurate and can vary from cooker to cooker. So use these whistle counts as a guide and figure out what works best for your cooker.
• Soaking: In the cases where soaking is optional, if you soak the pulses, it will reduce the cooking time. The cooking time I’ve mentioned is for unsoaked pulses.
• Slow cookers can be a great, convenient way to prepare pulses, just throw everything in in the morning and when you get home from work your food is ready. But some beans are toxic until they are boiled (for at least 30 minutes), and slow cookers can actually make them more toxic. If you want to use the slow cooker on these beans, boil them for 30 minutes before adding them to the mixture, or use canned beans which are already boiled.