The better and safer way would be to measure the free SO2 before
racking and do the addition based on that. If you want to ballpark it,
then I'd suggest 20-40ppm at the 2nd racking, probably closer to the
end of the range to be safe. I'd definitely do the free SO2 check on
the next racking if you're planning to bottle right after, aiming for
30ppm or so at bottling.

Pp

On Jan 9, 5:11 pm, "Trav77" > wrote:
> I've got a batch of Carignane wine aging in the carboy right now and
> have a question about how much sulphite to add at each racking. Here's
> what I've done so far:
>
> 50 ppm sulphite at crush, 50 ppm sulphite at the first racking (after
> ML fermentation was finished in November). My plan is to do a 2nd
> racking, adding oak chips, then leave it till the Fall - do a 3rd
> racking then bottle a week or so later.
>
> Given the sulphite I've already added, how much should I add at the 2nd
> and 3rd rackings? pH is 3.55-3.60.
>
> Thanks!