I know its a trivial detail, but I'm genuinely curious and struggling to find the answer.
Screenshot from in-game:
Fandom page's image:
The Fandom page had a better, larger picture, but I still couldn't tell what it said. However, the description of the item says:
The empty milk bottle is a cylindrical, white glass bottle with the company's logo built in to the bottle's shape.
So I thought, "Great, all I need to do is look at the company's logo. Where do I find the company logo, though? Aha! From the vending machine!"
So I then looked at the Fandom page for the milk vending machine. However, this was less enlightening than I had hoped. The company named on the vending machine is "Little Cobb Creamery", which, as far as I can tell, doesn't seem to match the embossed text on the bottle.
Alright, so that didn't work. Maybe if I search for Little Cobb Creamery I'll learn something? From the company's Fandom page I only learned this:
They owned many milk vending machines across the streets, as well as at least one creamery, which provided milk for the Medford area.
Fortunately, "creamery" was a link to the Fandom page for Parsons Creamery. However, the page was not terribly informative.
Comparing the text to the name "Parsons Creamery", I thought I was on to something at first: I could see an argument for the letters "P-A-R" (depending on the typeface), but when it came to the supposed "S", the embossment looks a lot more like a "T" to me. So I don't think it says Parsons Creamery, either.
For me, this is where the trail runs cold. What does the embossed text say?