Aluminum bottled water. Straw-less lids. Reusable cup systems. As concern about plastic waste grows, the search for sustainable packaging has gone mainstream.

Nicole Doucet and Jess Page were met with skepticism when they first tried to persuade retailers to sell their brand of bottled water. Consumers, the young entrepreneurs were told during those early sales calls five years ago, would not pay more for water packaged in aluminum containers instead of plastic.

It turns out their Chicago-based startup, Open Water, was just a bit early to the party. Food and beverage companies that cater to on-the-go consumers are rethinking their packaging amid growing concern about single-use plastics clogging up swaths of ocean...