[QUOTE=taxlady;1353260]Well, it was in the food section.
The brand I got is from the UK. It's KTC. It says it's for external use only, but I found this interesting letter: Mustard Oil | External Use Only
"The effects of erucic acid
from edible oils on human health are controversial. However no negative health effects have ever been documented in humans."
So what is a food grade mustard oil?[/
Well, I haven't seen it in my local supermarket but, then, I haven't looked. I would think that if you buy it in a grocery shop, a health food store or specialist Indian food store and it's with the usual cooking oils it should be "food grade". If in doubt I'd probably ask.
I suppose it's "food grade" because it's "clean" and isn't contaminated by noxious chemicals or foreign bodies and is safe for human consumption.