Whats the point of the Boil Times?

[Burndog]

Hello,
Seems like a dumb question but I understand the various time intervals regarding adding components and how they can relate to the end product.

But, I'm brewing this today:
Irish Stout, BIAB...
https://www.homebrewtalk.com/showthread.php?t=28239

And there are NO additions other than the hops added at the end of the boil.

So what is the purpose of boiling for 60 minutes if the arrest of sugar conversion is attained at 180. Whats happening in those added minutes after the wort reaches boiling temp?

 

[Qhrumphf]

1. DMS
2. Hop isomerization
3. Wort concentration
4. Flavor/darkening

1. DMS reduction is the big one, although the boil time needed varies based on the malt (and level of precursors) present. Some malts will allow less than 60 minutes. Pilsner malt according to common knowledge needs 90. However, that has been disputed and may not need as long. May be better expressed in percentage boil-off, and 90 mins may be a result of commercial brewing where boiloff rates are far, far lower than homebrew setups (5-8% or less per hour instead of 15-20% or more). With extracts it'd be a non-issue as the SMM/DMS is driven off during manufacture of the extract.

2. Most all recipes get bitterness from boiling hops. Some (low bitterness beers) could be flameout and later only, but that's not the norm. I believe it's above 185F that isomerization occurs, but it's most rapid boiling. You'll get *some* bitterness from flameout hops, especially if there's a long whirlpool, but not as much as boiling.

3. Concentration is a matter of the gravity you want. If you're fine with higher volume and lower gravity, that's fine. If you simply collect to your target volume instead of collecting more and boiling it down, that's fine, but you'll lose efficiency doing so. Also a non-issue for extract.

4. The last, unboiled wort will be paler than boiled wort, proportionate to boil length and will get a slight flavor difference. This is a subtle difference that may or may not be beneficial to the beer at hand and would need to be accounted for. This is actually why adding extract late in the boil is recommended.

And regardless, in this recipe the hops are added at the beginning of the boil, not the end. 60 mins means boiled for 60.

 

[Smellyglove]

For a stout I'd say Maillard reactions.

 

[Yooper]

The link is wonky, so I can't see the recipe, but I'd be really surprised at a stout recipe that only had late hops. Most stout recipes will have hops added at 60 minutes (at the beginning of the boil).

 

[Smellyglove]

The link is wonky, so I can't see the recipe, but I'd be really surprised at a stout recipe that only had late hops. Most stout recipes will have hops added at 60 minutes (at the beginning of the boil).

You have to scroll down past that wonky stuff. The recipe is solid, OP is has the boil times reversed.

 

[Burndog]

You have to scroll down past that wonky stuff. The recipe is solid, OP is has the boil times reversed.

What do you mean about confusing boil times?

 

[Yooper]

Oh, yes, I know that recipe well.

The hops are added at 60 minutes- which means you start the timer for 60 minutes and add the hops. When the timer hits 0, the boil is over.

That means that the hops are boiled for 60 minutes, and not added at the end. That makes a lot more sense!

When I add my bittering hops, I always bring the wort to a boil, and let the hot break happen. After that (about 10 minutes after reaching a boil), the foaming stops and then I add my hops and start the timer for 60 minutes. I assume that everybody does it that way, but I thought I would mention the "hot break" if you're not familiar with that.

 

[Jtk78]

What do you mean about confusing boil times?

When recipes show hop additions, the minutes are how long the boil is after the addition, not before. The recipe you linked has a hop addition that is boiled 60 minutes, not at the end of a 60 minute boil.

I've done a couple 30 minute boil when my hop additions are shorter than that. At this point in my brewing career (very short), I wouldn't boil for under 30 minutes. Other, more experienced members may disagree.

 

[Qhrumphf]

Ahh, hot break. That's another reason to boil. Although that one doesn't take long.

 

[Burndog]

Crap! put the hops in at the wrong end of the boil....

Any remedies to solve this?

 

[Smellyglove]

Crap! put the hops in at the wrong end of the boil....

Any remedies to solve this?

You will get some flavor which wasn't planned for with that addition. You can google "hop tea bitterness", and start there.

For a classic hop-confusion you did good, you could have added late hops at the start, luckily you just need to add bitterness, not remove it

 

[seatazzz]

I will also suggest reading John Palmer's How to Brew...available online for free and on Amazon or possibly your local library or bookseller. Fortunately homebrewing is one of those hobbies that have TONS of books, websites, and forums. Read read read!!! Palmer even takes you through a typical brew day (whether it be extract, partial mash, or all grain) step by step so you can get a good idea of how to proceed. I've got his Hydrometer appendix permanently bookmarked.