I bought a bag of toor dal (split pigeon peas) at a local Indian market. The brand is Santos, which appears to be a local Bay Area brand of beans and such.
On cooking the dal for the first time, I was a bit put off by the smell. It smells sweet - somewhere between maple syrup and WD-40, and this is also a bit perceptible in the taste of the dal. Afterward, I did some googling and found that toor dal is sometimes coated in castor oil for preservative purposes. So before I cooked another batch tonight, I followed the recommendation for oiled dal and soaked it in multiple changes of water for about 24 hours to get rid of any oil.
It does not appear that this dal is oiled - there was no obvious oil slick in the soaking water when I discarded it, and it had no smell before cooking. So I boiled it again and yep, it’s releasing that same sweet smell again.
Is this just how dried pigeon peas are supposed to smell when cooked, or is something else going on to cause this odor?