hey, had a brewday at the weekend, really just to test some new kit, and it was a definite learning curve.. !
ended up well overshooting the OG due mainly to a much larger loss during the boil than expected. gravity in FV was 1.061, moving me towards the big beer kinda area (that i soon intend to spend all my time in :p). i collected only 16.5 L in the FV.
i wasn't so prepared with yeast for it, so i chucked in one pack of US-05 rehydrated, then thinking of the gravity sent another half pack in dry.
as i say, not experienced with gravities over 1.060, but all i've read says to make sure you don't underpitch or it wont ferment fully. right now there's a decent 10mm head on it, but just wondering if anyone had any thoughts as to whether that was a sufficient amount of yeast as it is a smaller brewlength, whether/when it's too late to add more?
pitched enough yeast in high(ish) gravity beer?
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jaroporter
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eclipse
Re: pitched enough yeast in high(ish) gravity beer?
You'll be fine, I made a 10% beer with one packet recently. The yeast grows inside the fv anyway.
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jaroporter
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Re: pitched enough yeast in high(ish) gravity beer?
that does reassure me. cheers. 
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Kev888
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Re: pitched enough yeast in high(ish) gravity beer?
Mr Malty's pitching rate calculator can help with this - I don't know the date of your yeast but as an example (using the defaults) it says you need about 10g of dry yeast. You are correct that you need more for higher gravities, but in this case thats largely offset by it being a smaller batch. (BTW, if this happens again, you can top up the boiler towards the end of the boil to re-dilute it down to the desired OG).
Eclipse is correct that the yeast will grow in the FV; when you under-pitch they spend more time than normal in this propogation stage - which can slow things down or hinder the FG and affect the flavours produced, such as producing more by-products like diacetyl, esters and fusel alcohol. Similarly for over-pitching, there is less of a growth stage which can make things more rapid, but it can again affect flavours and body. There is also more chance of flavour problems from the yeast themselves (like autolysis flavours) as there are fewer younger/healthy cells created; more of them are older ones.
Happily, in practice I find that you don't have to be very precise though, which is good as very few of us home brewers can verify the number of viable cells in our yeast. Provided the pitching rate is 'about' right things don't seem to change wildly.
Cheers
Kev
Eclipse is correct that the yeast will grow in the FV; when you under-pitch they spend more time than normal in this propogation stage - which can slow things down or hinder the FG and affect the flavours produced, such as producing more by-products like diacetyl, esters and fusel alcohol. Similarly for over-pitching, there is less of a growth stage which can make things more rapid, but it can again affect flavours and body. There is also more chance of flavour problems from the yeast themselves (like autolysis flavours) as there are fewer younger/healthy cells created; more of them are older ones.
Happily, in practice I find that you don't have to be very precise though, which is good as very few of us home brewers can verify the number of viable cells in our yeast. Provided the pitching rate is 'about' right things don't seem to change wildly.
Cheers
Kev
Kev