Definitely mustard oil. It is the authentic oil to use for tikka. That said I wouldn't eat it if you turned it brown and called it beer, it's bad stuff. I have a friend who moved from South Africa at an early age and she has family all over the place there. One of her uncles went to the doctor with various ailments, mostly heart related, and the doctor told him to stop his wife using mustard oil and particularly to stop using fried mustard seeds.
The moral of this story:
South Africa is where Britain was in the 50's, only women cook?

Don't eat mustard oil ever, and only fry mustard seeds occasionally.