What Giggliato posted was as follows:The dead yeast cells covering ADY interact in an unknown way with the gluten in the dough.
The problem I have with the glutathione thesis is that its effect on protein is well known. In fact, the very first post I entered on this forum, at Reply 8 at http://www.pizzamaking.com/forum/index.php/topic,484.msg4159.html#msg4159
, was about glutathione. That was back in July, 2004. I have been paying attention to articles about glutathione ever since. Usually, the problem with glutathione is most pronounced when freezing fresh yeast. But it can also exist with frozen doughs. One can even purchase dead yeast to use to replicate the softening effects on glutathione, as well as contributing to a yeasty flavor in the finished crust. Tom Lehmann has written often on this subject. See, for example, Tom's PMQ Think Tank posts at http://thinktank.pmq.com/viewtopic.php?p=15803#p15803
I have made many frozen doughs and while I use more yeast (dry yeast) than normal to make such doughs, because of the damaging effects of freezing on the yeast, I can't say that I have ever experienced a softening of the dough because of glutathione. There may be some glutathione in such doughs but, like Craig, I would guess that it is there in very small amounts.
Hopefully, Giggliato will return to elaborate further on what he had in mind.