Mustard Seeds

As an aside, I've taken to toasting mustard seed before using it. I love the flavor that a brief toasting adds to a dish. Just use a dry skillet over medium high heat until they start to pop and become fragrant.

I too have been using brown/black and yellow/white and find the black ones to be much more flavorful.

Yes, just to confuse matters even more, black mustard is brown. Outside -- and yellow within.

Thanks all! I have been using yellow/white and brown/black that are all the same size with very good results. Just picked up some smaller sized brown-black today. I'll try them in my next batch.
The woman (from India) that I bought them from told me that there really isn't a black seed. The smaller seeds are the same variety as the larger brown ones. She added that the smaller one grow in southern India while the larger one grow in the north.

In theory, the black species should be somewhat more pungent than the brown. Personal opinion: I wouldn't think twice about subbing brown for black.

nothing much in terms of flavor, the brown ones are much smaller.

I have been using brown mustard seeds for quite a while when recipes call for black. I finally got seeds labeled 'black' from an Indian grocery. They are visually identical to what I already had. So, ?

The names for different mustard seeds are often confused and misused. White is commonly referred to as yellow, brown sometimes mistaken for black. But, yes, there are three; black being rare commercially.