Does cider require refridgeration

Apple cider does require refrigeration after it has been opened. Commercial cider undergoes a pasteurization process that kills most bacteria that would cause it to spoil. Once you open the cap and expose it to air, it can start bacterial growth. Even though Apple cider is acidic, it is not acidic enough to retard bacterial growth. In addition, it contains high amounts of sugar, which promotes the growth of certain bacteria, such as mold.