FAQ: How Do Beverage Dispensers Work?

There are two basic types of carbonated beverage dispensers: pre-mix dispensers with canisters of already-mixed drinks and post-mix or bag-in-box (BIB) systems. Post-mix beverage dispensers are used in fast food restaurants, bars, hotels and convenience stores. Usually, pre-mix beverage dispensers serve up the drinks at carnivals, fairgrounds and smaller stores.

Q: How do post-mix beverage dispensers work?

A: Post-mix systems come with syrup pumps, CO2 tanks and carbonators. Carbonators combine cold tap water with CO2 gas to make soda water or seltzer. The CO2 powers the syrup pumps. Dispensing systems have cold plates in the bottom of ice bins. Electronic valves control the amount of soda water and syrup that are dispensed. Push buttons or metal tabs, against which cups are pressed, activate the process for soda water and syrup to flow together into the cups.

Q: Which type of beverage system dispenses better-tasting drinks?

A: Post-mix systems are the preferred and most commonly used beverage dispensers. Pre-mix dispensers come with carbonators, CO2 tanks and pre-mixed syrup in stainless canisters. Soda is dispensed via dip tubes as CO2 pushes down from above the soda, which passes through cold plates into ice bins and out of simple spouts. Often called glorified soda in a bottle, passing through faucets, pre-mixed soda is considered a quick-fix drink and is not known to taste as good as post-mix soda.

Q: How do beverage carbonators work?

A: Carbonators are at the heart of beverage dispensers. They are in tanks, typically 20 pounds each, which mix CO2 with water. An attached pump pressurizes water above the CO2 gas pressure, forming soda water. Some commercial establishments add water filtration systems for better tasting soda, which also preserves the life of beverage dispensers. Beverage dispensers must stay at temperatures no greater than 38-40 degrees, or the carbonated product tastes flat.