Sometimes I need to take a break during a brew day, so I get the situation where I might have tossed the first wort hops into my kettles around 10 am, then sparged on top of that to hit my preboil volume, then I leave that sitting for maybe 2-3 hours, and only get around to firing up the boil around 12:30 or 1pm. Is that too long? I’ve done it a couple times before and the beers have been fine, but just wondering what the accepted best practice is.
FWH helps to solublize the aromatic hop oils. More hop oils remain in your beer.
If you added your normal late-addition hops (low AA, yet desirable aromatic oils) as your FWH addition, you should be fine, even with a long steep. It may even be more “efficient” from a hop oil solubilization standpoint. Giving the oils time to sit around in the warm wort gives the volatile, yet normally insoluble, oils and resins time to oxidize into more soluble compounds that can be retained in the boil. Otherwise, the boiling process (and fermentation process) will drive off the volatile oil compounds.
I’m not sure what the chemical reactions are, but I agree that there probably is some sort of binding reaction or conversion of those volatile components into less volatile components that resist boil-off.