90 min brew question-

[Jeff20578]

I’m brewing a beer that has a 90 min boil. The 1st hop addition is at 30 - other then boiling off excess liquid, what’s the purpose of a 90 min if you don’t have hop additions close to the start?

 

[Velnerj]

There's a belief out there that pilsner malt will produce DMS. Which is a precursor to diacetyl and a 90 min boil will get rid of all DMS avoiding the dreaded diacetyl in the finished product.

Many brewers these days don't find this to be true with modern modified malts.

I've never done a 90 min boil and I haven't had any issues (there's my anecdotal experience).

 

[shoengine]

Maillard reactions. Changes the flavor and color.

 

[Beernik]

Grain bills with a lot of Pilsen malt can develop DMS off flavors of you don’t give them a long enough boil. Another 30 minutes on the boil is cheap insurance against a beer that tastes like creamed sweet corn.

 

[doug293cz]

There's a belief out there that pilsner malt will produce DMS. Which is a precursor to diacetyl and a 90 min boil will get rid of all DMS avoiding the dreaded diacetyl in the finished product.

Many brewers these days don't find this to be true with modern modified malts.

I've never done a 90 min boil and I haven't had any issues (there's my anecdotal experience).

DMS and diacetyl are unrelated. You are correct that 90 minute boils have traditionally been recommended to minimize DMS in beer, which causes a "cooked corn" or "cooked vegetable" off flavor. Boiling wort slowly converts preexisting SMM into DMS. It takes 30 - 40 minutes to convert half of the remaining SMM to DMS (depending on wort pH.) The DMS formed evaporates rapidly, as it's boiling point is about 100°F. Residual SMM can convert to DMS during slow cooling or other storage conditions, so getting rid of as much SMM as possible during the boil reduces the potential for formation of DMS in the beer after the boil.

Traditionally, low kilned malts (Pilsner being the lowest kilned) have more SMM content than higher kilned malts, so have the potential to create more DMS, or leave more residual SMM in the beer, if not enough is converted during the boil. So, historically, brewers have tended to boil high Pilsner content worts longer. It is often claimed that more modern Pilsner malts have less SMM than historical malts, so the need for an extended boil is reduced.

Brew on

 

[Spikybits]

other reason for 90 min boil is to enhance the maillard reaction which darkens the wort - i believe 90 min boil will also enhance some caramel favors but this is anecdotal

 

[doug293cz]

other reason for 90 min boil is to enhance the maillard reaction which darkens the wort - i believe 90 min boil will also enhance some caramel favors but this is anecdotal

Yes, longer boils do darken the wort, but this is usually undesired in Pilsners and other light colored beers.

Brew on

 

[Kickass]

Op, what style is the beer you’re brewing?

 

[Jeff20578]

Thanks!

 

[Spikybits]

Yes, longer boils do darken the wort, but this is usually undesired in Pilsners and other light colored beers.

Brew on

Yep, agreed but OP just said a beer!

 

[shoengine]

Did this thread just get merged? Otherwise there is a in the Matrix...

 

[shoengine]

There's a belief out there that pilsner malt will produce DMS. Which is a precursor to diacetyl and a 90 min boil will get rid of all DMS avoiding the dreaded diacetyl in the finished product.

Many brewers these days don't find this to be true with modern modified malts.

I've never done a 90 min boil and I haven't had any issues (there's my anecdotal experience).

I've gotten that confused before too. Diacetyl causes the butter flavor in beers.

 

[doug293cz]

Did this thread just get merged? Otherwise there is a in the Matrix...

Yes. Duplicate threads.

doug293cz
HBT Moderator

 

[Gusso]

90 minutes? I've been doing 30 since my rebirth to brewing last year. Even with lagers, I don't see an issue. It's all I've been doing.

 

[Gusso]

I do compensate with hop additions, though...

 

[cactusgarrett]

other reason for 90 min boil is to enhance the maillard reaction which darkens the wort

Pretty sure there's something else going on (like concentration) besides the oft cited Maillard Reaction, since that needs temps of 280F+ to occur.

 

[doug293cz]

Pretty sure there's something else going on (like concentration) besides the oft cited Maillard Reaction, since that needs temps of 280F+ to occur.

I think you are referring to "caramelization", which does require temps hotter than boiling, but different sugars have different onset temps for caramelization. Caramelization is driven strictly by temperature.

Maillard reactions are reactions between an amino acid and a starch or sugar. They can occur in boiling wort, whereas caramelization cannot.

Both caramelization and Maillard reactions result in darkening.

Brew on

 

[cactusgarrett]

[Maillard reactions] can occur in boiling wort... result in darkening

I used to just blindly accept when people suggested that Maillard was at play until, in one of the plethora of podcasts I spend too much time listening too, I vaguely remember a pro brewer suggesting this isn't the case because the temps weren't hot enough. The reason I looked into it closer and saw (you quoted the same reference I did) " The reaction is a form of non-enzymatic browning which typically proceeds rapidly from around 140 to 165 °C (280 to 330 °F)"

What am I missing?

 

[doug293cz]

I used to just blindly accept when people suggested that Maillard was at play until, in one of the plethora of podcasts I spend too much time listening too, I vaguely remember a pro brewer suggesting this isn't the case because the temps weren't hot enough. The reason I looked into it closer and saw (you quoted the same reference I did) " The reaction is a form of non-enzymatic browning which typically proceeds rapidly from around 140 to 165 °C (280 to 330 °F)"

What am I missing?

"proceeds rapidly" is the important qualifier. Most chemical reactions follow what's known as Arrhenius temperature rate behavior. In summary, the rate of reactions increases exponentially as the inverse of the absolute temperature decreases. This means that there is not a specific temperature at which the reaction starts to occur, but rather that it pretty much occurs to some degree at all temperatures, just significantly slower at lower temps. You get more reaction at lower temps with low activation energy processes than with high activation energy processes. In the context of "proceeds rapidly" for Maillard reactions, I would take that to mean that you see visible results in just a few minutes. With boiling wort we are talking about a time frame of an hour +/-, and less dramatic darkening than the browning of a loaf of bread.

Brew on

 

[cactusgarrett]

I'll buy that - good enough for me to go back to considering that (and caramelization) to be the case in the kettle.

 

[BrewnWKopperKat]

What am I missing?

Have you seen the "Wort and Malt Extract Color Development" presentation [link to PDF] that's at Briess's Resource Library?

It has charts that show how much wort darkens during the boil.

 

[dmtaylor]

The reason recipes are written for 90 minute boils though is for fear of DMS. Fortunately, this fear is mostly no big deal for homebrewers in the 21st century. Safe for us to shorten to 60 minutes, or even a little less.

If I wanted darkening and serious Maillard reactions in my beer, I'd be boiling way longer than 90 minutes. Back in the 1800s, a lot of breweries were boiling for 3-8 hours. Beer must have tasted much much different then.

 

[Spikybits]

Pretty sure there's something else going on (like concentration) besides the oft cited Maillard Reaction, since that needs temps of 280F+ to occur.

Sources? Alot if not most sources do cite maillard reaction as occuring with a longer boil. Concentration is an affect of boil off. Most brewers account for boil off rates and will start with a certain amount of liquid prior to boil to achieve a specific amount going into the fermentor.

 

[BrewnWKopperKat]

Concentration is an affect of boil off.

There is also the idea of a "concentrated" boil - where the boil SG is much higher than the target OG in the fermentation vessel.

With DME/LME, one can add half the water and all the extract at the start of the boil. This results in a boil SG that's roughly 2x the recipe OG. It apparently also leads to wort that is "darker" than expected and has "unexpected" flavors.

One could also do this (concentrated boil) with an "all grain" wort: mash a SG 88 wort, then dilute it to OG 44 in the fermentation vessel. FWIW, I did a "one-off" BIAB Red Ale (OG 42-ish) using an OG 75 wort. The beer "came out fine". The color was "to style". No "unexpected" flavors.

 

[dmtaylor]

One could also do this (concentrated boil) with an "all grain" wort: mash a SG 88 wort, then dilute it to OG 44 in the fermentation vessel. FWIW, I did a "one-off" BIAB Red Ale (OG 42-ish) using an OG 75 wort. The beer "came out fine". The color was "to style". No "unexpected" flavors.

I've actually done this on my last two batches. Usually I am a small batch brewer of about 2 gallons average batch size, and I've always brewed on my stove top, I don't use a big propane burner, etc. But for these two batches, I needed to make 6 gallons for two big events. So I decided to aim for about 1.080 (and I succeeded) with about a 3-gallon batch each, then added distilled water to the fermenter to hit around 1.040. Worked like a charm. Both beers were the best I've made in recent history. Neither had significant darkening or caramel flavor effects, not at all.

 

[cactusgarrett]

Sources? Alot if not most sources do cite maillard reaction as occuring with a longer boil.

It's right there in the link I included and further quoted. However, Doug did a good job of explaining that despite boiling wort being below the temp cited, it's a rate of reaction thing. Since I've been brewing for longer than I care to mention, I'm trying force myself to give some critical thinking behind the info that people pass down. Previously, a lot if not most sources also said to transfer to a secondary...

 

[doug293cz]

There is also the idea of a "concentrated" boil - where the boil SG is much higher than the target OG in the fermentation vessel.

With DME/LME, one can add half the water and all the extract at the start of the boil. This results in a boil SG that's roughly 2x the recipe OG. It apparently also leads to wort that is "darker" than expected and has "unexpected" flavors.

One could also do this (concentrated boil) with an "all grain" wort: mash a SG 88 wort, then dilute it to OG 44 in the fermentation vessel. FWIW, I did a "one-off" BIAB Red Ale (OG 42-ish) using an OG 75 wort. The beer "came out fine". The color was "to style". No "unexpected" flavors.

You can certainly do a concentrated wort boil when doing all grain, but your lauter efficiency, and therefore both mash and brewhouse efficiency, will take a hit. Not an issue for extract brewing because there is no lauter step involved.

Brew on

 

[BrewnWKopperKat]

Not an issue for extract brewing

With "extract", there is a observation in How To Brew, 4e (chapter 9) that concentrated boils lead to "wort darkening and the development of off flavors". I didn't see any additional details.

Obviously, wort darkens when boiling. How much? The numbers from the presentation (above) suggest "not much".

Hard to have a discussion about "off flavors" that don't have specific names.

 

[Steveruch]

With "extract", there is a observation in How To Brew, 4e (chapter 9) that concentrated boils lead to "wort darkening and the development of off flavors". I didn't see any additional details.

That can be countered by boiling for a shorter time. Or not at all; extract doesn't have to be boiled.

 

[BrewnWKopperKat]

With "extract", there is a observation in How To Brew, 4e (chapter 9) that concentrated boils lead to "wort darkening and the development of off flavors". I didn't see any additional details.

That can be countered by boiling for a shorter time. Or not at all; extract doesn't have to be boiled.

Understood. I've seen your "no boil (pasteurized)" recipes in Zymurgy.

eta: my curiousity/questions are about understanding concentrated boils (boil SG 88-ish, target OG 44-ish). If a concentrated 60 min boil (the Amber Ale I mentioned) works with 'all-grain' wort, would it also work with fresh DME/LME?