How useful is the boil ?

[TheArmada]

I'm asking as a beginning brewer.

After the mash it seems like I've got perfectly fine wort just waiting to be fermented. I mean havn't I extracted most of the sugars from the grain, into my water, during the mash ? Why should I boil for an extra hour ?

Seems to me like I am losing a lot of valuable wort to evaporation during the boil.

 

[mdabbles]

Boil is critical - you need to break down proteins in the wort so that it can convert sugars to alcohol.

 

[Yooper]

I'm asking as a beginning brewer.

After the mash it seems like I've got perfectly fine wort just waiting to be fermented. I mean havn't I extracted most of the sugars from the grain, into my water, during the mash ? Why should I boil for an extra hour ?

Seems to me like I am losing a lot of valuable wort to evaporation during the boil.

The boil is crucial. First, the grain itself is loaded with lactobacillus and the wort will sour within about 24 hours without a boil. Secondly, you want to evaporate off the DMS precursors, called SMMs, so you shouldn't cover the boil pot. Also, hops utilization requires a boil and a good time line to extract the majority of the hops ability to isomerize is about 60 minutes. You could boil longer, and get a few more IBUs out of the hops, but 60 minutes is a good compromise between maximum IBU contribution and fuel and time consumption.

There are a couple of no-boil beers- Berliner Weiss is sometimes one. That's because it's a sour beer, so it doesn't need to have the lactobacillus killed.

 

[finsfan]

You dont use any wort from evaporation, you actually increase the amount of sugar concentration because only the water evaporates. First of all, the boil is necessary to sterilize the wort from any contaminants and prepare it for fermentation. Also, the boil is required when adding hops to the beer. I wouldn't skip this step at all, its pretty important

 

[RonPopeil]

the boil is where the magic happens. the boil sanitizes your wort for starters. without that your chances of getting clean beer are greatly reduced.

the boil also evaporates a lot of compounds that don't taste good. i believe a few of them are sulfur based so without a boil you'll get something that smells of rotten eggs.

the boil clarifies your beer. proteins extracted in the mash end up clumping together and falling to the bottom.

at the very least the boil will allow you to layer hop flavors and add other seasonings to a brew.

boiling is crucial. i'm giving you a massive redux on what's going on. if you want your mind blown post this in the brewing science sub forum.

 

[GrogNerd]

want to know what beer from unboiled wort would smell like?

forget to clean the grains out of your closed tun. after a day & a 1/2, stick your face down into it and take a big ol' whiff.

 

[emjay]

Check out no-boil Berliner Weiss

 

[TyTanium]

The boil is also useful for

1) cleaning your mash tun
2) prepping your fermenter(s)
3) relaxing with a homebrew

 

[ghack]

Huge number of chemical changes occur in the wort during the boil that make it beer. As has been mentioned, protein extraction, blow off of volatile and undesirable compounds (DMS or the cooked corn flavor for one), sterilization. But also the Mailliard reaction occurs, darkening the wort and producing complex flavor compounds. And then we get to the hops, getting the Alpha Acid and bittering compounds out takes a good boil. Extremely important step.

 

[JeepDiver]

Boil is critical - you need to break down proteins in the wort so that it can convert sugars to alcohol.

There are lots of reasons for the boil but this isnt one of them. Conversion happens during the mash

 

[HopSong]

BUT, do you actually HAVE to bring it to a boil or would, say, 200* work? The reason I ask this is that new Kickstart brewing device does not bring the wort to a boil and they say it is controlled to less than a boil but enough to boil off the DMS

 

[kh54s10]

BUT, do you actually HAVE to bring it to a boil or would, say, 200* work? The reason I ask this is that new Kickstart brewing device does not bring the wort to a boil and they say it is controlled to less than a boil but enough to boil off the DMS

That is a controlled system that most homebrewers cannot achieve. It also will cost $1500 and only do 3 gallons.

 

[GrogNerd]

There are lots of reasons for the boil but this isnt one of them. Conversion happens during the mash

you're both correct. there's conversion going on all over the place

the mash converts complex starches into simple sugars

yeast convert those simple sugars into alcohol

 

[JeepDiver]

you're both correct. there's conversion going on all over the place

the mash converts complex starches into simple sugars

yeast convert those simple sugars into alcohol

And the boil has nothing to do with conversion into sugars

 

[PseudoChef]

Boil is critical - you need to break down proteins in the wort so that it can convert sugars to alcohol.

Proteins have nothing to do with starches converting to sugars and neither does the boil.

 

[PseudoChef]

Back in the old BJCP test format, one of the popular essay questions was to list and explain 5 reasons why we boil wort - Yooper did a pretty great job getting to the nitty gritty.

Boil is critical - you need to break down proteins in the wort so that it can convert sugars to alcohol.

Proteins have nothing to do with starches converting to sugars and neither does the boil.

 

[Yooper]

Back in the old BJCP test format, one of the popular essay questions was to list and explain 5 reasons why we boil wort - Yooper did a pretty great job getting to the nitty gritty.

Damn! I didn't name five though!

 

[Ramitt]

BUT, do you actually HAVE to bring it to a boil or would, say, 200* work? The reason I ask this is that new Kickstart brewing device does not bring the wort to a boil and they say it is controlled to less than a boil but enough to boil off the DMS

That is an interesting question I would like to see solid research on. I would guess it would only be very useful for people with fairly automated systems.

 

[GrogNerd]

Boil is critical - you need to break down proteins in the wort so that the yeast can convert sugars to alcohol.

There are lots of reasons for the boil but this isnt one of them. Conversion happens during the mash

And the boil has nothing to do with conversion into sugars

Proteins have nothing to do with starches converting to sugars and neither does the boil.

I fixed where he went wrong (underlined) but otherwise, he's NOT talking about starches to sugar. which, AGREED, is done in the mash and has nothing to do with the boil

he says "sugars to alcohol"

 

[JeepDiver]

I fixed where he went wrong (underlined) but otherwise, he's NOT talking about starches to sugar. which, AGREED, is done in the mash and has nothing to do with the boil

he says "sugars to alcohol"

Well he was saying that protiens (which is wrong it is starches) are broken down in the boil (remember the OP was talking about the boil, not the yeast)

So he was wrong using protien instead of startch and wrong for saying it happens in the boil instead of the mash.

The comment about yeast was in realation to what they do with the products of the boil and not the main subject of the sentence.

Reading comprehension 101

 

[Facinerous]

Here you go dude. A link that describes why you boil.

Hops and boiling

 

[GrogNerd]

you've never seen a hot break in the boil?

that's proteins. maybe not "breaking down", though that's a good way to describe it, but coagulating. in the boil

not starches, not unicorn farts, not someone's pointed little head

proteins. in the boil

with me so far? going too fast? I'll use smaller words if I'm getting too technical for you

reading comprehension 001