abv calculation

[moobli]

am i doing this right

og =1.048
fg=1.021

og -fg=1.027 x 1.05=1.078

1.078 divided by 1.027=1.049=4.9%abv

just my ipa is down at 1.021 after 8 days although the room temp had dropped to 18 c
just roused it and padded it with pillows round ill check again tomorrow just thought 1.021 was a bit high for a brewers choice ipa

[jubby]

Your ABV calculation is a little high there moobli. OG-FG then divide by 7.8 will give you an approximate figure. In this case about 3.5%.

[moobli]

thanks wanted to check i was doing it the right way

thanks again for the correction
ill see what happens after the rowse

[jubby]

Don't get too hung up on final gravity figures, it will still be good beer. Most of the kits I brewed never reached a decent gravity figure, but they still turned out well.

[moobli]

i dont usually bother with it at all
just expected the brewmaster choice ipa to get down a bit lower than that
i usually do three readings over three days and if it stays the same then bottle the following day

[pdc]

A Quick search on the HMRC website give a sliding scale fudge factor.

but it is: fall in gravity times fudge factor.
The higher the fall the higher the FF

(1048-1021)x0.129=3.482%

Round down to 3.4%

[vacant]

After taking your FG reading, if you use around 85g of priming sugar in 23 litres you can add another 0.2%.

[Lillywhite]

Most 40 pints kits come out in the range 4- 4.5 %ABV and there appears to be 101 different versions of the calculation available. Just do a google search to see.

Don't get hung up on the %ABV, as long as it tastes OK then that's all you should concern yourself with.

[trucker5774]

I have used several different calculations to work out ABV.............I reckon the Customs and excise must have a good idea of what's going on, so I go for the easiest to remember in the middle of their range..........................gravity drop X 0.13 = ABV........."thimples"

[moobli]

cheers all just checked again and after a gentle rouse (rowse) its down to 1.018 at 20%c
just wanted to get the most out of a £20 kit and a drink i have never had before that i can recall
being a lager drinker and trying this ipa with the light spraymalt i wanted something more than a lager but nothing too bitter in a drink, not taste way like a boddingtons

got some realy nice st peters ipa bottles all ready to go
and a ready drinking date of oct 31st

[Lillywhite]

cheers all just checked again and after a gentle rouse (rowse) its down to 1.018 at 20%c

Leave it longer to see if you get it down to at least 1.014.

[moobli]

instructions said 7 days but im at day 9 now and it is moving down was hoping for 1.012ish
it got a little froth head again after it being roused so i will leave it till sunday then do the readings again

dont know if im expecting too much from the kit or the ipa

[Lillywhite]

instructions said 7 days but im at day 9 now

Ignore the instructions. Primary fermentation period depends on many factors, not the least the ambient temperature.

Oh and ignore the reference to 'your brew will be ready to drink after 14 days'.

[moobli]

its going to be at least a month before it is drunk after bottleing
learnt my lesson with that one
bottle it
in the warm for 10 days then out into the shed for the rest of its life only to be brought in to drink
building up a stock pile for SWMBO halloween party

[moobli]

now down to 1.016 at 18%C
so its getting there