A take-away near where I use to live ran by British Pakistanis had been found out that they wanking their load in to the Garlic sauce and Mayo sauce.
They were closed down, but reopened a few months after.
I was, but never had sauces on my food apart from BBQ. I really don't want to know if I was a victim, but I only heard them cumming in Garlic and mayo. So I think I got away with it.