I visited Japan in early November and I was at a airport VIP lounge where there is an automatic beer filling machine. It's called a "reverse beer tap". I took a quick video and uploaded it to youtube. Here is the link:

[youtu.be]

It used a special glass with an inlet at the bottom that seems to be spring loaded. You then push the glass down and it opens the seal and fill the glass with beer from the bottom. When done you pull the glass off the machine. So I am guessing the glass pushing down opens the valve, makes a seal, then there is a solenoid that dispenses a fixed amount of beer to the glass, then the glass is removed. As I removed it I tried to see if any beer is spilled from the seal being opened...I didn't see any.

I was also told there is a version of this machine, where you are presented with say half a dozen choices of beer and you make the selection and push the glass in. Since there is only one valve, which is shared by say six different beer supply lines, then when you filled a glass of Guinness, then a glass of Coors, will the glass of Coors not contain some residual of the Guinness from the last fill?



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We have had that kind of beer filler at a local (25 minutes away in the small town of Orland, Calif) upscale restaurant here for many years.

I've never been a fan of it and prefer regular glasses. I believe the reason for them is "less beer waste when pouring."

I hadn't thought of your excellent question and next time there (about once every 6 months) I'll definitely ask them. One bartender there said he wasn't a fan of it however I didn't ask him why.

Here is a link to one mfr:

[www.bottomsupbeer.com]

These have been around for a while but never really caught on. To your question about residual beer from previous fills, it's no different then the beverage guns that bartenders use to dispense soda water, Coke and tonic. The cross contamination between selections is so slight as to be not noticable.