How come sometimes sodas on tap faintly taste like other sodas?

How does this happen? I mean, I get it if a soda flavor is changed and that particular tap tastes like the previous soda temporarily, but I’ve seen cases where soda taps remain, uh, infected for shockingly long periods of time, i.e., months or years. Why doesn’t the prior soda’s residue get washed out for good? Is there some sort of nefarious crossing of soda lines going on here? What’s the straight dope?

Soda fountains are not as well-calibrated as the machines making soda at the bottling factory. The mix of water, flavour syrup and CO2 is often a little bit off, so your Sprite can taste a little bit like 7-Up. But this wouldn’t make your Coke taste like Orange Crush, though.

I’ve noticed the3 variability in flavor too, like most people, but it now occurs to me: the vendor wants to cut corners and say, “water down” his syrup from Coke, do the suppliers have inspectors of some sort? Or is the problem just his, and he loses money cause his Coke tastes like shit?

If I were a brand-owner I wouldn’t tolerate that.

I’m not sure how you’d water down your Coca-Cola syrup. Doesn’t that stuff come in a sealed bag?

Yeah, but the guy at the store adds the bubbly water. Store means diner, etc.

You’re assuming the fountains are properly cleaned or even cleaned at all. I can’t remember where, but I’ve read horror stories of mold and worse in the fountains and ice bins. I suspect the health inspectors don’t always (if ever) open up the back/front of the fountain for inspection. I’ve seen workers just switch the tubing from a non-working flavor to working one, especially if it’s a popular flavor.

If my soda has a hint of another flavor, I toss it because I don’t know what could be causing the mixup.

Edit: I’ve been in restaurants at closing and the most I’ve ever seen anyone do is wipe down the outside of the fountain and empty the overflow tray. Maybe the morning crew does a more through cleaning, but that means it’s been left uncleaned overnight.

I’ve seen people put their almost full cup directly up to the spout (i.e. covering the spout) to make sure they get a full cup. Sometimes after taking a drink or doing a refill.

Ewww…I’ve just convinced myself not use soda fountains! :eek:

BTW, I used to know a Health Inspector and while he never gave specifics, the would recommend not eating at certain McDonalds’ for awhile. If a McDonalds was questionable, imagine the conditions of mom and pop places.

Since the owners of Sprite and 7-Up are competing companies, you’re not going to get both out of the same machine.

When I worked at Burger King, we disassembled the nozzles and cleaned them, every single night.

I’d get a drink from that location!

Here’s the cleaning instructions from Coca Cola:

"Dispenser cleaning is quick and easy – the process takes less than 15 minutes to complete. Just follow the protocol established by the equipment manufacturer, which The Coca-Cola Company endorses: wash your hands, mix the cleaning solution; remove nozzles and diffusers and soak them in the sanitizing solution; brush nozzles and diffusers and then air dry; wipe down the machine. And you’re done!

The following steps, coupled with Coca-Cola products, deliver a great-tasting drink on a consistent basis:

Daily: Clean the dispensing valves

Wash hands
Remove nozzles and diffusers from the dispensing valves and clean them with a special nozzle brush and chlorine-based sanitizer solution; soak nozzles and diffusers in the sanitizer solution for about 3 minutes; replace after they dry
Clean underneath dispensing valves with the sanitizer solution and a dedicated brush; dry with a clean towel
Wash the drip pan
Wipe down the entire surface of the dispenser
Empty the ice bin and clean the sides of its interior
Clean the ice chute
Weekly: Clean the syrup connectors

Wash hands
Disconnect the syrup line from bag-in-box (BIB) units; shake out any remaining liquid
Soak the connectors in the sanitizer solution for about a minute
Shake BIB connector to remove any excess sanitizer and reconnect each connector to the corresponding BIB
Monthly: Clean the inside of the ice bins

Wash hands
Unplug the ice maker; scrub the inside of the ice bin and chute with a nylon brush and the sanitizer solution
Wash the condenser fins with a dedicated hard brush; clean the air filters, if they are used
Check the water filters to make sure they are current
Maintain the valve and syrup line product labels:"

I’ve never seen any of this done, but maybe the magic gnomes do it in the morning! :slight_smile:

I think the poster was comparing the taste, not that they were mixed. However, Costco and Amazon sell soda fountains and syrups, so if you roll your own, it’s possible.

I frequently just get water from the fountain. This is usually a side control on one of the flavored taps. I hold it down to let it run for a bit before filling my cup, but often I can still detect a trace of the flavor in it. Enough is left in the mixer valve to be tasted.

In the case of bag-in-box dispensers there are two adjustment screws at the dispenser that determine the proportion of the mix, so you can indeed dilute the product if you wanted to.

I can’t speak about the newer machines, but back in the 1980’s I worked at a theme park. My job was working on the soda machines, we had hundreds on site. At that time, the syrup came in five gallon tanks that were hooked up in the back of the stand and ran through stainless steel lines to the machine. A water line ran to a filter, then a carbonator and then to the machine. I carried a “brix cup” to check the ratio of syrup and water. I would remove the normal nozzle, twist on my brix nozzle and then dispense it into my cup. The cup had two chambers, one for the water and one for the syrup. There were markings on the cup to make sure the ratio was right. I had a rotation set up to where every machine was calibrated at least three times a week. While it was rare for them to get wildly out of calibration, the soda company was a sponsor in the park and they were adamant about quality. The crews in each stand were responsible for cleaning the nozzles and the rest of the machine nightly. It was my job to sanitize the lines from the tank to the machine monthly, as well as change the water filters.
Most of the time, all of this was enough to keep everything tasting like it should…except for root beer. Root beer was the bane of my existence. If a crew would accidently hook up a root beer can to anything other than the root beer line, it would alter the taste of that line forever, even after sanitizing multiple times. I never understood why, I would just go to the stand and replace the entire line and tell them to never do it again. Hook up cola to the orange by mistake or any other flavor? No problem, switch it back, let the soda run for a while and we were back in business. Root beer though, and the line was toast.