Quote Originally Posted by Bob-D659 View Post
Unbreakable plastic PET type plastic ones are as good as glass, Usually found in the beverage aisle complete with water or soda type drinks in them.

They are way better than concertina type bottles.
Common PET bottles, even for carbonated beverages, are oxygen permeable over time. So they may be perfectly adequate - but not as good as glass (at least in theory).

Some PET bottles have better oxygen barriers than others - I think those are used more for drugs/medicines and similar uses (rather than food). I do use PET bottles for working solutions.