Most aluminum cans have a plastic lining inside of the can. Assuming the lining was undamaged and applied properly, it should prevent the beer from reacting wit

Most aluminum cans have a plastic lining inside of the can. Assuming the lining was undamaged and applied properly, it should prevent the beer from reacting with the can for a long while. Usually, the oxidization is with the oxygen which was already dissolved in the beer during brewing (important to have some for fermentation) but depending on ingredients oxidization can happen without the presence of molecular oxygen.