Picture it: you’re picking up a six pack of beer, and you may not even realize: do you prefer beer in a can, or beer in a bottle? While cans are becoming far and away more common than bottles, here’s something you may not know: the material used to package your beer could actually have an effect on your beer’s shelf life, depending on the kind of beer.
A team of researchers at Colorado State University, in partnership with New Belgium Brewing, set out to explore the ways in which cans versus bottles affect the flavor (and therefore freshness) of beer. Their findings weren’t as clear cut as they might have expected, noting that different kinds of beer seem to respond differently to packaging technologies. The team’s work is described in a recent issue of ACS Food Science & Technology.
Specifically, researchers concluded that for amber ale beer, bottles appeared to keep them fresher longer. For India Pale Ales (IPAs), the type of packaging material used made less of a difference.
But why?
It all has to do with chemical reactions that occur in the beer itself, as the water, ethanol, and myriad flavor compounds in a beer interact with the packaging material. When all of these things interact together, the chemical reactions that occur can cause certain flavor compounds to break down, negatively impacting flavor. These chemical reactions can also lead to the creation of new, unexpected compounds that were not intended by brewers, leading to unintentional, sometimes unpleasant, changes in flavor. Some work has been done on how beer ages in different packaging, but these studies have been limited to only one type of beer and to studying a small range of compounds and reactions.
To test how packaging material affect beer, researchers looked at both cans and bottles of amber ales in chilled environments for about a month, followed by a roughly five-month period at room temperature (simulating how beer is often stored).
Overall, researchers found that amber ale was the beer most affected by changes in packaging material. The fact that IPAs saw less change in their flavor profile could likely be chalked up to the higher amounts of polyphenols present in the beer due to higher hop volumes, which can help minimize oxidation that occurs in a can or bottle.
These findings could help brewers make more informed decisions about the best ways to package and store their beer.
Sources: Science Daily; ACS Food Science and Technology
