Yesterday, I bought a SodaStream home soda-maker.

[MiddleFingerMom]

74. Maybe, but I can't see why they wouldn't just say "you don't wanna contaminate the system"...

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... and by not being specific about that point, they might leave themselves open to
lawsuits by anyone AFFECTED by a contaminated system -- I DEFINITELY don't see
them doing THAT.
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Plus, I've seen anecdotal testimonies in several areas about the mess caused by
carbonating a substance other than plain water.
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AH!!!!! Your keg is a closed system, I'm assuming. And when you pour a beer from
it, a certain amount of head is produced -- which you can normally pretty much
control (though from my bartending days, I think a freshly-tapped keg puts out a
LOT of initial foam). You have to "open" the freshly-carbonated bottle immediately
with no way to control the outrush of gases and fluids.
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I know I added flavoring too quickly to a JUST-made bottle of carbonated water
and it actually bubbled over very quickly, though not too badly. Something tells
me the effect would be MUCH worse if the flavoring had been in the water at the
time of carbonation.
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