Post-mix refers to the system in which a flavored syrup (concentrate) of the soft drink is shipped to the retailer, usually in a returnable tank or a disposable bag-in-box container.
At the point of sale, the soft drink is mixed to order from the post-mix syrup, chilled and purified water, and carbon dioxide (from a gas cylinder), and usually dispensed from a soda fountain or soda gun.
A post-mix dispenser is a more sophisticated device than a premix dispenser.
The post-mix system is suitable for outlets that serve large amounts of soft drinks quickly, such as a sports stadium or a busy fast-food restaurant.
Bag-in-box packaging provides an efficient and convenient distribution format for post-mix syrups.