Post-Mix Dispensers 101

When it comes to post-mix carbonated beverage dispensers, not all maintenance steps are as easy as they might seem. So says Scott Hester, co-owner of Mesquite, Texas-based Refrigerated Specialist and a 31-year service veteran who’s
well versed in post-mix equipment. Hester once arrived for a dispenser service call and found that the wrong-sized water filter had been stuffed into a filter housing that was too small for it.

“The staff didn’t know better, and when they installed the filter the carbon spilled out and clogged the filter,” Hester recalls. A good filter was ruined, and the unit had to be flushed and cleaned.

This is one of several areas where faulty post-mix equipment maintenance can make your drinks–and by extension, your profits-go flat. Keeping carbonated beverages crisp and perfectly balanced is a matter of making sure all its components–air, syrup and water–come together as designed.

What To Do Every Day
For advice on daily upkeep for post-mix dispensers, we spoke with Hester and Roger Reif, a Manitowoc Foodservice Group service manager based in Sellersburg, Ind. To start, both pros say that removing and cleaning spray nozzles is an essential daily task. Nozzles should be unscrewed and soaked in warm soapy water at day’s end and re-installed the next day.

The reason? In a machine that’s running sugary syrups, it doesn’t take much to restrict the flow through nozzles, says Reif. Adds Hester: “[If operators] go a week without dropping the nozzles you can tell.” Syrupy blockages can build up quickly. Reif adds that maintaining clean nozzles is so important, some of his
customers keep two sets of them handy to swap out, if necessary.

Next, your staffers should be cleaning the drain troughs that catch the overflows and drips of your sugary drinks. Troughs also attract debris, such as stir sticks, that can quickly clog drain lines. Debris can also find its way into other places; on units with refillable ice bins, your staffers should check for twist ties from ice bags
that can accidently fall in, says Reif.

Reif also recommends using hot, but not scalding, water to flush out plastic troughs. The water must be hot enough to melt the syrup sugars but moderate enough to not crack the plastics. While cleaning the drain troughs, staffers should use warm water and a cloth to wipe down splash guards and other surfaces.

The Ice Component
Ice is a critical component of post-mix dispensers, regardless of whether they have built-in ice makers or a refillable bin. Hester says all the basics of ice machine maintenance apply to beverage machines, though sometimes they are overlooked.
In addition to using proper water filters for your location’s water quality, Hester says managers must insist on a regular cleaning schedule that includes emptying ice bins, scrubbing the interior with scale-removing solution and using a sanitizing rinse. Be sure staffers always refill ice bins to keep the cold plate cold, he adds.

If you’re baking anything on site, your post-mix equipment maintenance will be more involved. Baking releases airborne yeast spores that can quickly find their way into ice bins, according to Hester, who says his post-mix equipment service calls to bakery locations occur at twice the rate of non-baking operations.
The cleaning steps above can reduce ice contamination and service calls.

What To Check Throughout The Month
Several other dispenser components should be monitored throughout the month, says Hester.

For example, syrup lines are largely maintenance free, but that doesn’t mean you should ignore them. One area in particular can present challenges: the lines for slower-selling product. Slow lines can dry out between servings, which then can lead to off-tasting flavors for the next serving a customer or server draws. One way to reduce issues is to pump cleaner through the lines, says Reif, and there are several brands to choose from.

Another potential problem, though less common, is the buildup of mold in areas where syrup is left exposed. Hester says regular inspection and wiping of lines, connectors and surrounding areas should keep this buildup to a minimum.

Items to check on a monthly basis also include bag-in-box connectors. These should be removed and soaked in a 5% bleach solution and rinsed in warm tap water, says Reif.

However, keep in mind that removing connectors can alter the mixture of carbonated water to syrup, which is the basis of each drink’s taste. Hester advises operators who perform these cleaning duties to also learn how to adjust their product’s brix to ensure the desired flavor.

“Everyone says you should clean out your syrup valves leading from the box and to the fountainhead, but few people do it,” says Hester. Just as important, “you should be checking your brix periodically, based on your volumes, to make sure you’re not wasting money on the syrup you’re selling.”

Pressurized CO2 lines should also be periodically checked for leakage. Reif says you can use soapy water applied to connection points to detect tell-tale air bubbles. Hester adds that sometimes a leak can be detected audibly when the beverage is drawn. Neglecting the lines or connections can negatively impact product
flavors, Hester says.