It won't eat the plastic away, but unless it's food-grade plastic it might pick up (i) chemicals left over from the manufacturing process (ii) tates or flavours left from previous contents. Also, plastic is slightly porous, so small quantities of gas can pass through, so it may oxidize over time (or in the case of beer, may oxidize and go flat). This process will be fairly slow though.
I did Swish in PET some 20 years ago, it was all good, and I am still her
Dogger
"Listening to someone who brews their own beer is like listening to a religous fanatic talk about the day he saw the light" Ross Murray, Montreal Gazette
For about $3 you can buy 1125ml plastic bottles from many Homebrew shops. Not only do these hold as much as a Still Spirits flavour bottle makes, but they look pretty cool as well
Of course my friend, i was just clarifying because at the cost of essences ( still cheaper than buying) some ppl would be turned off if they only got 1.125L out of 1 essence, my recomendation if you like bourbon or scotch is to try the Tennesse, gobblers and Kentucky oak chips, they are bloody fantastic ( or so im told )
My favourite is the Blueberry Schnapps More expensive than the whiskey/rum but is definately worth it. The Still Spirits Whiskey is pretty sweet as well, very caramel-ly
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