The ruins of a "high production" brewery have been unearthed in Egypt. . .

 or rather rediscovered. British archeologist discovered it earlier, but apparently didn't appreciate what it was.

And what it was, was a brewery that was capable of producing 22.400 liters of beer at a time.

22,400 liters at a time.

That's quite a lot.

The significant thing, moreover, is that the brewery dates to 3,000 BC, some 5,000 years ago. So this means that Egypt was mass producing beer, at least from this facility, 5,000 years ago.

What would it have been like? Well, that's a big guess.  There's been some efforts to brew it, but that involves a lot of guessing in and of itself. All we can say for sure is that they brewed it, and apparently quite a lot of it.