Imagine the following machine: it looks like a cross between a soda bottle recycling machine, and a soda can vending machine.
The user puts into it an empty two liter bottle, the machine scans the barcode, weighs the bottle to be sure that it's empty, and displays to the user the cost of refilling.
After user then puts in his money, the machine sprays hot steam at the cap and neck of the bottle to sterilize it, grabs it and takes the cap off, sprays a more steam on the inside of the bottle, and then fills the bottle up with soda made from syrup (soda concentrate) and carbonated water (just like a soda fountain does), recaps the bottle, and returns it to the user.
The cost (for the vending machine owner) of the syrup, carbon dioxide, and water used to make the soda is very very little -- probably pennies. Thus, the machine could charge the user much less for a refill than the local supermarket charges for a new full bottle.
Plus, the user is saved from the effort of recycling his empty bottles, and doesn't need to spend money on the soda bottle deposit.
For those who don't like the idea of reusing bottles repeatedly, it would be almost as cheap to have a machine that doesn't use the user's empties, but instead was loaded with clean, new, empty, bottles and brand name labels, and filled the bottles from the syrup on demand.-- goldbb, Mar 29 2009 The idea is good but quality control will be hard to maintain. When I worked for a cola distributor we would have to check the pre-mix machines' sugar content with a refractometer and then adjust the carbonation to get the flavor right.
If either one is off...gahk.-- 2 fries shy of a happy meal, Mar 29 2009 I saw this baked in my local supermarket but with bottled water. You could bring any sized bottle from one gallon all the way up to 5-gallons. The machine would fill your bottle and then cap it off for only 39 cents.-- Jscotty, Mar 29 2009 In some parts of the US the water is so terrible that there are actually shops dedicated to purchasing filtered water. You can buy the jugs from the shop or you can bring your own. They make good money too!-- Jscotty, Mar 29 2009 Probably 21 Quest, it's been awhile.-- 2 fries shy of a happy meal, Mar 29 2009 My dad (a coin-op vending company owner) often said that a good cup-vend soda was superior to can vend. The key word was "good" and, as 2 fries pointed out, the adjustment could be rather...subtle.
The real issue I see is the one people are already having in refiling water bottles: microbial contamination. If there are problems with water bottles, what happens when you add food (sugar... er, high fructose corn syrup) to the system? I don't know that steam will cover it.
I did just see a 1 gallon water vendor at Meijer yesterday that had a UV sterilizer.-- cindik, Mar 29 2009 With plastic bottles, which are vulnerable to getting scratches (which can provide a safe harbor for microbes), steam might not suffice.
(Well, not scratches, precicely, since noone's putting sharp pointy things in their bottles... but if you dent a bottle inwards, and straighten the bottle, there will be damage to the bottle where the dent had been, on both inside and outside.)
Perhaps steam + UV would be enough? You might then need bottles which won't be harmed by UV :)
Glass bottles might be a good alternative.
Or, as, I said at the very end of the idea, the machine could keep it's own supply of sterile bottles.
It would need to be a bigger machine, but it would still be able to store more (empty) bottles (all the bottles in a single hopper) and more soda (syrup) than is possible with pre-filled bottles.
It could also still be cheaper than pre-filled bottles, since the machine's owner avoids the cost of shipping water.
Regarding quality control: Couldn't the machine have a built-in refractometer, and do it's own adjusting of the carbonation? And as for water quality, the machine could also have it's own filter.-- goldbb, Mar 30 2009 i like the glass bottle idea. you can use a very small CIP nozzle to pressure wash the interior and you can fill and cap them in a die. Plastic is simply too flimsy for the kind of re-use that we are talking about. As for the mixing valve, a more effective (read "expensive") design could be used because it wouldn't be exposed to the abuse that a public cup vend suffers. Since we are producing a fixed volume you could use dosimeters and a blending chamber for the liquid ingredients and a direct liquid CO2 squirt into the bottle right before the cap is crimped on.-- WcW, Mar 30 2009 After thinking it through I suspect that the economics of a conventional vending machine that also gives you credit, even pays you cash for returning the deposit containers that it utilizes, are far more viable. Such a machine would process and refill containers but with a functional surplus to allow for impulse and first time purchasing. It would need to be considerably larger than a conventional machine and IMHO would need to vend multiple products to pay for itself.-- WcW, Mar 30 2009 Really were talking about re-inventing the deposit bottle system that was the mainstay of beer, soda and dairy until the invention of the pull tab aluminum can and the onset of LDPE for food. 100 years ago people would have laughed at the thought that this was an "invention".-- WcW, Mar 30 2009 Yes please. I used to try to do this the hard way with an empty 2-liter bottle, a local gas station soda fountain, and a funnel. It was so annoying I gave up and switched to tea. [+]-- gisho, Mar 30 2009 random, halfbakery