A while ago I said something like; Every hop addition at different times has influences on beer other than the bitterness vs flavor/aroma debate. For instance 60 minutes favors isomerization which maximizes bitterness stability. 30 minute favors polyphenols. (ref Colin Kaminski ), etc. etc. And everyone gave me a cookie and I went home. Anyway: The main effect of polyphenols on flavour stability is probably situated in the mashing and wort boiling steps (Liegeois et al., 2000; Mikyska et al., 2002). In particular, polyphenols extracted from hop during wort boiling significantly contribute to the reducing power and effectively diminish the nonenal potential of wort (Lermusieau, Liegeois, & Collin, 2001). Sensory experiments (Mikyska et al., 2002) also confirm the positive effects of hop polyphenols, during brewing, on flavour stability. I know that (E)-2-nonenal leads to oxidation. And of course I might be missing the forest for one tree. For instance typically HB isn't shipped, is not normally cellared, etc. And I'll admit that most of this is beyond me. But I hope that it's food for thought. p. 374 http://nfscfaculty.tamu.edu/talcott/Food%20Chem%20605/Spring%202011%20Class/2011%20Papers%20and%20Class%20Presentations/Review-Beer%20Ageing.pdf
thanks for posting...definitely interesting. What I'm trying to figure out is what are the 30-min hops going to add that the 60-min hops wouldn't? Wouldn't the polyphenols from the 60-min addition bind to the nonenals. You also get plenty of polyphenols from the mash. There are i believe thousands of polyphenol compounds and each behave differently so...uh, ultimately I remain unconvinced that I personally need it.
On the first part, I don't know. Colin didn't give any reasons. On polyphenols, somewhere in there I believe that its states that it's a 70/30 malt/hops contribution. But I wonder if that's style dependent. Or is there a point of diminishing returns? Yes, polyphenols is a large group. So how different are the malt vs hop polyphenols? Listening to Palmer polyphenols need to be a balanced with the style/recipe. So maximizing them isn't always good or needed. But no 60 or 30 minute does cause me to question pure hop bursting. Anyway I do think that this is a good exercise in examining what hops will do for you based upon when they are added. Well at least for one time frame. Also, I do remember Colin talking about at times a hop molecule will bind to a sugar molecule. When this happens the molecule survives the boil and is released by the yeast during fermentation. sorry, I'm babbling.
