Did Abraham or Noah keep kosher?
I believe they knew the clean and unclean food designations and didn't eat unclean. For example:
Gen 7:2 Of every clean beast thou shalt take to thee by sevens, the male and his female: and of beasts that are not clean by two, the male and his female.
If by "kosher" you mean the traditions and rules built up by the Jewish religion over time then probably not.