inspector gadget wrote:Thanks for the welcome guys, yes I have had a Megahome airstill for a while now and recently finished my first wash and am pleasantly surprised with the results. Needing to find out more I did some searching and am glad I found the airstill guide pdf, will be putting that to good use over the coming weeks. Wash was a turbo48 8kg mix and the technique i was using was to throw the first 50ml then keep 750ml and bin the remainder of the wash, A visit to a brewshop threw me a bit when the guy said no... keep the first 800ml then save the next 350ml and add to the next batch of wash and so on... time to delve a bit more and here I am... hopefully able to input as well as output IYKWIM...
regards and I'll update my profile as soon as I can...
Gadget..
The dump the foreshots (first 25-50 mls) technique is good/correct, as that's where any methanol produced by the ferment (all ferments produce some - but that's enough of a safety margin) will appear and come out.
The then collect the next 800 mls is the basic method suggested by the still makers for a nice, easy, straight forward method that anyone can follow - but it is a bit wasteful. There is still some alcohol left in the rest that you'd routinely dump.
Part of your learning will be about "making cuts". While that's not so necessary for sugar wash, as the sugar is already refined before use and while any alcohol taken after the initial 800 mls won't have much of a different flavour, it's a waste just to flush it.
I routinely just start my smart still, remove the foreshots (into the screenwash bottle of my car) and then let it run until it's distilled out about 2 litres - I then put that into a container of some sort. I do that to all of the batch of 25 litres of wash.
Once it's all been through once, then I measure it and make sure it's less than 40% ABV (if it's higher, then I water it down with reverse osmosis water from the local aquarium shop - as locally water is very hard), then re-distill it. You get about 80% or so ABV. I don't have to bother dumping foreshots as you will have already removed any methanol the first time (all fermentation will produce small amounts of methanol but it boils lower than ethanol, hence dumping the foreshots as that's where any will be).
Then I take the 800mls, but I leave the still running and anything that comes out later, right down to between 20 and 10% will go back into the rest that's waiting to be distilled a second time.
I let the distillate down with RO water as above, but to as close to exactly 40% ABV as I can (that's the regular drinking strength and the level that any flavouring essences you might use will taste correct at)
I always carbon filter (I have an older style "Z" filter but anything you can use should help remove any possible off notes in the distillate). The carbon filter does a better job at a lower strength - though you can filter at high strength if you want, just that you'd end up changing the carbon more often..........