Well, I've had problems towards the end of the "secondary" below 70F with
the fermentation slowing to the point of looking stuck. I warmed it to about
76F and it resumed, still slow because this as below 1.000 SG, but moving.
This isn't an attempt to start another fementation, just to make sure it
keeps going. My guess is that there is so little CO2 being produced at this
stage that it will have little effect on the volatiles even if it is warmer.

"Don S" > wrote in message
om...
> > No, the idea is to get it off the main body of the settled yeast and
into a
> > carboy for secondary fermentation which will take it down to full
dryness.
> > Keeping some sugar and raising the temp in the secondary fementation is
to
> > make sure it really does go to dryness. I'm doing a cool primary
> > fermentation to try to keep as many volatiles as possible.
>
> There is no real primary and secondary fermentation unless you
> think of the first day or so during the reproductive phase of
> the yeast and the subsequent anaerobic phase as everything else.
> The name primary and secondary was invented by the kit makers
> to separate the explosive first fermentation when the kit could
> be in air contact from the later slower fermentation when air
> contact was not desireable and was thus done under an airlock
> in a carboy.
>
> Thus, there's no real need to boost the temperature after the
> rack into the carboy to start "secondary" fermentation. If it
> was fermenting in the primary it should ferment in the carboy.
> If it gets stuck that's a different story. Keeping some sugar
> to make sure it goes to dryness almost sounds at odds with itself
> but I understand what your aiming at.
>
> Don