score:5
There's no literal indication. Apparently (correct me if I'm wrong on this), the humans knew which animals were pure and which weren't even before of the flood. You can observe this when God tells Noah to take the animals into the ark:
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. Gen 7:2
In the following verses Noah doesn't question this order, neither asks God for which animals were pure or not. So, this is an indicator that humans knew some of Moses' Laws (probably all). About this, some people believe that God engraved the Moses' Laws onto the hearts of the humans, but this is just a theory.
About the meat: The biblical text doesn't say God forbid to eat meat before the flood explicitly, according to Gen 1:29-30 (KJV) he gave like herbs and seeds for the human to eat:
29 And God said, Behold, I have given you every herb bearing seed, which is upon the face of all the earth, and every tree, in the which is the fruit of a tree yielding seed; to you it shall be for meat.
30 And to every beast of the earth, and to every fowl of the air, and to every thing that creepeth upon the earth, wherein there is life, I have given every green herb for meat: and it was so.
He didn't forbid it, neither allowed it. But later, after the flood, He gave the humans authority to eat animals' meat.
Cheers
Upvote:2
We can tell what "clean" means by what Noah did with them. They were not "clean" for eating, because God granted Noah permission to eat any moving thing (Gen 9:3). They were "clean" for sacrifice, because that is what Noah did with them (Gen 8:20).
Sacrifice to cover sin was instituted by God when He clothed Adam and Eve with skins (Gen 3:21). It was taught to Cain and Abel (Gen 4:4). So we must assume that God clarified it to Noah either directly or through his forefathers so that Noah understood the animals to be used for that purpose. Extra pairs were included on the ark because they would be used later for both food and sacrifice (not just food) so that the world would need plenty of them.