Hop Boiling.

[SHIELDS EXILE]

If I were to hold a wort at say95 degree,sC, for,95 minutes, would I get the same hop extraction as I would get froma100c boil for 90 minutes. In both cases I would have used9000 degree minutes of heat ? Or is there something special about the boiling point.

[john luc]

Yes you will extract hop oil but the main reasons for boiling are,
To sterilize the wort
To stop the enzymatic activity of the mash
To concentrate the wort
To boil off unpleasant aroma compounds
To coagulate proteins so they will drop out
To extract bitterness from the hops
To adjust wort color and flavor

 

[orlando]

As violent a boil as you can manage is better than a simmer, for al the reasons above, particularly proteins and tannin coagulation.

[Jocky]

As violent a boil as you can manage is better than a simmer, for al the reasons above, particularly proteins and tannin coagulation.

Not sure I agree with that. Movement of the surface of the liquid is sufficient for mixing purposes, you don't need a volcanic boil.

[orlando]

It's not about mixing it's about the collisions.

[TheSumOfAllBeers]

I believe Stella Artois / ABInbev have a process where they bubble CO2 through the wort at sub boiling temperatures that achieves the same objectives.

In their case it’s about being a good ecological citizen and using less energy/smaller carbon footprint.

It would imply that wort agitation is the key factor. I would have some concerns about hot break formation, but a macro lager producer has alternative ways of dealing with those problems than homebrewers

[SHIELDS EXILE]

I think John Luc, explains int very well,many brewing books tend to state things as law, but do not say why.He sums it up well.

[Dave S]

I believe Stella Artois / ABInbev have a process where they bubble CO2 through the wort at sub boiling temperatures that achieves the same objectives.

In their case it’s about being a good ecological citizen and using less energy/smaller carbon footprint.

It would imply that wort agitation is the key factor. I would have some concerns about hot break formation, but a macro lager producer has alternative ways of dealing with those problems than homebrewers

Not sure bubbling extra CO2 through the wort is a sound approach to reducing carbon footprint.

[f00b4r]

I believe Stella Artois / ABInbev have a process where they bubble CO2 through the wort at sub boiling temperatures that achieves the same objectives.

In their case it’s about being a good ecological citizen and using less energy/smaller carbon footprint.

It would imply that wort agitation is the key factor. I would have some concerns about hot break formation, but a macro lager producer has alternative ways of dealing with those problems than homebrewers

Not sure bubbling extra CO2 through the wort is a sound approach to reducing carbon footprint.

It might be stuff they have captured from a previous fermentation.

[Kev888]

As with so many things, one could do it but it introduces more problems so there would need to be a reason that justified it. Often industry has such reasons of course, but I doubt many homebrew situations would.

If I were to hold a wort at say95 degree,sC, for,95 minutes, would I get the same hop extraction as I would get froma100c boil for 90 minutes. In both cases I would have used9000 degree minutes of heat ? Or is there something special about the boiling point.

Extraction isn't even linear with time, so it wouldn't be quite as simple as that. For example a 60minute boil doesn't have half the extraction of a 120min boil. I believe temperature to be similar. IMO it would work, with some significant side effects such as mentioned above, but it wouldn't be a linear extrapolation.

[TheSumOfAllBeers]

I believe Stella Artois / ABInbev have a process where they bubble CO2 through the wort at sub boiling temperatures that achieves the same objectives.

In their case it’s about being a good ecological citizen and using less energy/smaller carbon footprint.

It would imply that wort agitation is the key factor. I would have some concerns about hot break formation, but a macro lager producer has alternative ways of dealing with those problems than homebrewers

Not sure bubbling extra CO2 through the wort is a sound approach to reducing carbon footprint.

It’s probably captured co2 from fermentation and they can recapture that co2 if they choose to.

The big guys for all their asshattery , are actually pretty good on green matters