wrote:

Jack Keller says, buried somewhere on his website, that the SO2 gas
released inhibits pectic enzyme. And like Droopy says, yeast use must
proteins to grow, and the pectic enzyme you added works just fine as
yeast food.


This question pops up on a somewhat regular basis - if you do a search
on the archive, there is a post from a guy from Scott Labs who said
that's true only at free SO2 levels of 200ppm and more, so there is no
issue in sulfiting and adding pectic enzyme around the same time.

Pp