All-Grain Mashing: Add hot water to grain, or add grain to cold water and heat slowly?

I am no chemist, but I am a former chef and total tight ass when it comes to designing an "ultimate method" for everything.

One thing that has always bothered me about home brewing is the idea that for the dough in step of mashing, everyone over-heats their strike water, knowing that it will cool off some once it hits the cooler grains. I'm not too concerned about hitting the right temperature in the end. I am concerned about what is happening for the few seconds that the 170-180 degree water is reacting with the cracked malt.
Does the hot water not kill or destroy... something... in the grain that we'd want to keep? My mind immediately goes back to bread making. Yeast is killed by any temperature above 105-110 degrees F. But yeast also goes dormant and doesn't really do it's job below 40 degrees F. So... when making bread, you don't want to use HOT water, but you also don't want to use ice cold water. (there is a whole thing about delayed fermentation in bread that says to use really cold water and let the dough chill in the fridge for 3 days... but that is a whole different post). So what people sometimes do, is they want the dough temp to be 105-110 degrees, so they add 125 degree water to the flours/salt/yeast mix and the whole thing ends up at 110. But... this is terrible, because for the 5-10 seconds that your water is cooling down 10-15 degrees, the very fragile yeast is dying. It usually ends up "working out in the end" because there is enough yeast left to do the job. But... to me it is an imperfect concept.
Same with beer. Would it not be better to add the grain to cold (or room temp) strike water, and then raise the temperature slowly over a low flame until you reach your target temp without the thermal shock to the grain?
I know that some complex recipes call for letting the mash rest at specific temps for specific times, raising the temp mid-mash. This bring in one additional question that must be asked then...
Is it okay to stir a mash right in the middle of the mash time. Or better yet... continuously stir throughout the mash. If you do not use the insulated cooler method, but instead opts to mash in your boil kettle over a bottom-heat-source... is it okay to stir the mash to distribute the water heat throughout the mash, or will this agitation have a negative effect on the outcome.

These are some pretty chemistry centric questions, so please only comment if you had read or seen something that addresses these questions. I know "it will work" by adding hot water to cold grains, etc. I am interested in, as I said before, "the ultimate method. Ha ha ha... Please don't laugh. I know it's goofy.

 

There is a separate forum for all grain, with a lot of info on mash. Here is my over simplified explanation.

You are steeping the grain to extract flavor and make a conversion starch to sugar.
There is no yeast in the grain, save for wild.
Sugar plus yeast plus fermentation yields the kick.
You pitch/temper the yeast to the wort post boil.
In the end do what makes you happy, keep notes and let your taste buds guide you.

Hoe this helps
Eric
cia 4/90

 

It takes a while for the hot water to convert the starches in grain to fermentable sugars. Cold water would do this even slower. This is a process (adding hot water to colder grain calculated to end up at a certain temperature) that has been used for centuries...

As said there is no yeast already in the grains, so no concerns there.

Heating cool water with grains in it creates more problems than it solves (for most brewing systems). You have to stir constantly to get the temperature consistent throughout the mash. You don't want to scorch the grain. And you don't want to miss your mash temperature.

For most brews you have a target mash temperature for the style of beer you are making. You want the mash close to this temperature for as long as possible. By slowly heating the mash you don't really know what your mash temperature was.

I think you are really over analyzing this.

 

This phrase is DEFFINITELY not new to me. Lol!!! Yeah. I am certainly an avid over-thinker. But... it's not because I simply like to make my life miserable. It all kind of stems from scratching that deep mental itch of, "why is this done this way?" This is something that I think any Homebrewer is familiar with. I don't think anyone gets into home brewing because they actually thought they'd save money over buying craft brews. Although now, at $12+ per six (or 4) pack, the scales have definitely tipped towards homebrewing to save cash.

To clarify, I am not concerned about killing yeast. I used the bread analogy just to show that "something" can be harmed by doughing in at temperatures higher than you intend the final mash temp to be. I imagine it is a conversation that I'm not going to really be able to have in an online forum, because the reality is, no one really knows. You'd probably need to do several dozen tests using a $500k gas chromatograph to analyze what all gets dissolved into the wort at X temperature, and X2 temp, and X3 temp... Where as most people are just going to fall back on the, "It's been done like this for centuries," mindset.

To address the scorched grain, and continuous stirring to heat cold water... I didn't mean to add the grain to ice-cold water and slowly bring up 10 gallons of cold porridge to 150+ degrees over a period of 4 hours. I was talking about taking 120 degree water, doughing-in, and then raising the whole mix up to 155 (or whatever) rather than starting out at 170 (too hot) and dumping grain into this over-heated water and bringing that temp down. I imagine the first few cups of grain are being affected/harmed in some way. I'm mostly thinking that you are dissolving harsh compound that are only soluble at higher temps.

But... like I said, I don't think the cost to benefit ratio is there for doing any real experimenting. I was just wondering if I'd find a fellow over-thinking brother at arms who knows what I'm talking about and has a knowledge bomb for me.

 

I like the idea of thinking "what if?" and avoiding the ""It's been done like this for centuries," mindset.", but I think this route is flawed.

To further clarify my ideas on this: When mashing you are often targeting a very narrow temperature range for a particular style. For instance to get a dry beer you might be targeting 149 - 150 degrees. For a heavy stout you might target 154-155 degrees. If you start at 120 and increase the temperature until you hit even 149 degrees how long would that take? Many recent exbeeriments have led to the idea that conversion might be complete in as little as 20 minutes. So if it takes 20 minutes to stabilize your temperature?? What was your mash temperature?? Somewhere between 120 and 149. Even worse would be the stout. To get a sweeter fuller flavor you would mash hotter. Given the longer time to raise the temperature of the mash you would actually be getting a drier beer than you wanted. Even if you tried to account for that, it would be very inaccurate.

 

As for your second question, it is ok to stir your mash. Recirculating mash systems where the wort is drained from the bottom and returned to the top of the kettle are just another variation on this theme. Having the wort circulate repeatedly through the grain has much the same effect as stirring the grain. I usually stir a little at the beginning of the recirculating processs.

 

Preheating the mash tun helps lower the strike water temp, though this depends on your specific mash tun.

The strike water probably denatures some of the available enzymes in a given grain bill but not to an extent that is significant, at least from my brewing experience. Nor does it seem to be evident that there is any significant impact from what I gather from other homebrewers, they hit their target OG and variance from that tends to be more obvious efficiency issues.

Its not a matter of "its been done like this for centuries," its a practical matter, mainly one of actually producing beer without going to lengths that would require an expensive GC-MS and other lab equipment along with significant hours. And of course, $$$$.

Big beer producers look to maximize efficiency and lower costs, so perhaps there is some research out there on it.

 

You are not completely over thinking this.

I have seen a few references to 'shocking' the grains when mashing in at a temp higher than what the target is. I can not say where or when, or what/who my source is, but i am sure that it is in here somewhere.

From what i remember, it is nothing detrimental, but it can lead to a loss of a few efficiency points in the end.

That would seem to make sense since the enzymes that covert the starch in the grains into fermentable sugars have some pretty specific ranges that they work in. Just try playing with that mash temp and you find that a jump from 148 to 152 will net you subtlety different beer in the end.

Anyway i have no sources to cite, nor am i an expert on the subject. Keep digging and let us kniw what you find.

Cheers

 

For those of us that mash in a plastic cooler adding the grain to pre heated water is the only way.

 

I pre-heat my cooler with hot tap water and use an on line strike water calculator, so my strike water isn't over-heated, it is at the proper temperature for what I'm tying to accomplish. Enzymes take a while to react to water temperature, the mixing of hot water and grain doesn't seem to cause any harm.
Sure you can stir your mash, but if you use a cooler, you don't have to, just add the hot water and the grain, put the lid on and go do something else for an hour or so.
Mashing in a kettle, constantly stirring and adding bottom heat is Total PITA and you'll get constant temperature swings.

 

When you put yeast into hot water (like 150F or above) they die, pretty much instantly. The enzymes that do the conversion are not living creatures and it takes some time to destroy them from heating. If you look at the term "mash out" you will see that the grain bed has to be heated to ~170F and held there for 10 minutes to completely denature the enzymes. Thus, adding your grain to water that is above the mash temp, then quickly adding the grains to bring the temperature to the mash temp probably doesn't destroy any enzyme needed for conversion. With my mash, I usually have all the grain added and the mash at the proper temperature within a couple minutes which doesn't give the enzymes much time to denauture.

 

Another way to handle this would be to warm your grain to your mash temperature, then your strike water would also be at mash temperature. It is just, IMO, an unnecessary step to take. And equipment (to heat the grain) that you don't need to buy.

 

This... right here... is that lightning bolt response post that reminds me why and how much I love the internet and home brewers! Thank you @kh54s10. My brain is one that gets stuck on "a question," and until I have a good rock solid, "Because..." to answer that question, I will always feel kinda like my beer isn't as 100% good as I can physically get it. It's a weird character trait, and I'm sure I need Adderall or something. But here we are. So thanks for squashing this one!

 

Good question and interesting answers. Cheers!

 

It's called free thinking and is what advanced mankind out of the caves. It's not anal, it's admirable.

TomVA

 

I believe all human progress is due to the lazy and dissatisfied. The lazy, because they say "this is too hard, I'll find an easier way", and the dissatisfied, because they say "this isn't good enough, I'll find a better way". Congratulations on being more human than most.

 

@Dolmetscher007 , I too am a classic over-thinker and pondered this same question years ago. As already stated above, the detrimental effect of "shocking the grain" to enzymatic activity is minimal. Our hobby is one of constant exploration and adjustment. There are so many ways to skin a cat, so here are a few things to consider:

1) Step Mashing: has also been used for centuries. More specifically decoction mashing was the primary method used where percentages of the mash where boiled and then added back to achieve step mashes. They had no thermometers back then. If your concern is avoiding shock then try step mashing (protein rest to saccharification rest). Efficiency may improve a few points and some may argue this approach leads to more well rounded wort. To me step mashing is unnecessary with most of today's highly modified malts but it does provide you with more control and certain styles of beers or ingredients benefit from it.

2) Equipment will dictate approach: It's difficult to step mash a traditional cooler style MLT. Before my current eHERMs rig I used a 8 Gal Gott cooler. For my bigger beers I never had enough room to add more liquid to step the mash and decoctions are a PITA. Over time I really understood my system and added some predictable factors in like MLT pre-Heat Temp (120*F), and grain temp (78*F) Having brewed enough on the system, I was able to dough in within 3 minutes or less and consistently hit my target temp +/- 1*F. The only variables I had to worry about were target mash temp and affect of environmental temp. Now with a eHERMs system it's WAY easier to hit temps and even step mash.

3) RDWHAHB

 

If you are concerned about denaturing enzymes, add any adjunct grains first, such as unmalted wheat, oats, barley, corn, caramel or roasted malts, rice hulls, etc. These grains will absorb their share of the heat, lowering the temperature to some degree prior to adding the enzyme containing base malts. If your recipe consists of 100% base malts then there is no concern as these contain far more enzymes than needed for efficient conversion. For example, if your recipe contains a high percentage of unmalted grains, such as a witbier which may be 50% unmalted wheat, it would be wise to add the wheat (and rice hulls if using) first, mix these well to ensure they have absorbed their share of the water and heat, then add the malted barley. I have no evidence that this is beneficial, but having been homebrewing for 18 years, I have had similar worries about denaturing enzymes during dough in and I have developed these habits. It requires no extra work except that when I mill my grain, I mill the adjuncts into one bucket and base malts into another.

 

To your concern about what happens adding the grain to the "over heated" water, the answer is not much. The temperature stabilizes quickly. The process of mashing is used to allow enzymes to convert compounds in the grain to other compounds. The most important part of the mashing process is allowing enzymes to convert starches to sugars. There are other parts that can be done, such as breaking down proteins to get a lighter bodied, clearer beer. Each of these parts is done at a specific temperature. It takes time for enzymes to denature when above their optimal temperature range. The temperature of the water and grain will stabilize before any significant amount of the enzymes for starch to sugar conversion are denatured. Any loss of those enzymes can be accomodated by increasing the mash duration. Further, you can determine if there are unconverted starches using an iodine test.

As for why it's so common to heat strike water to a higher temp and add your cooler grain to reach some target mash temp like 152F, part of this has to do with equipment and part of it has to do with the desired final product. Not everyone has a system for significantly raising the temperature of the mash (e.g. RIMS or HERMS). Hence, they have to pick a single mash temperature, then use a given volume of water at a given temperature to reach that target temperature when mixed with a given weight of grain at a given temperature.

As for why you pick that exact temperature, there are essentially two enzymes of importance when it comes to converting starch to sugar. One enzyme operates at the lower end of a temperature range and breaks the starches down entirely into fermentable sugars, the other enzyme operates at the higher end of a temperature range and breaks starches down into a mix of fermentable and non-fermentable sugars. The amount of non-fermentable sugar in your wort after mashing will impact how sweet or dry your finished beer is as well as affecting how full or light bodied it will be.

As stated by another poster, if you start cold and slowly warm the entire mash, you'll generally end up with a very light bodied beer. That is not an appropriate technique when you want to brew a full bodied beer.

So to answer your question, it is of little concern to put cool grains into over heated water, and the style of beer you intend to brew will dictate the technique you use for mashing.

The way you control temperature is dictated by what you intend to brew.

 

fwiw, I underlet the strike volume as fast as my pump can handle with the temperature set to whatever BS2 says will hit the initial mash temp. I've actually never had a problem with FG on any batch so even assuming some enzymes are lost (say, the bottom most inch of the grain bed that takes the direct hit from the hot liquor rising up through the FB) there's always been enough to handle the grain bills, even the 120 point beast that is my imperial stout. 'Course, that one is like 18 inches deep in the MLT so there's a hella lot of grain on top of the "strike zone"

Cheers!

 

It sounds like by controlling the ramp up temp to mash, you create a separate variable of mash time. If you neglect the stabilization period of a traditional mash, then time is no longer constant. You may need to mash for 75 minutes to get the same effect of a 60 min mash. The total mash time would be a function of starting temp and deg/sec of the heat source. Your logic makes sense, but it sounds like a trade of of variables. This gets me thinking though, if i had a pan large enough, i could mash in the oven. (My oven goes down to 150F).

 

Thanks, it's good to hear from a fellow chef. But let me warn you, don't rock the boat too much. Much of what is posted on brewing forums is copied and pasted verbatim hundreds of thousands of times with no one questioning the legitimacy of the content or researching beyond a casual Google search to find more of the same copy and paste. One other thing I've noticed is the The Mr Kool-Aid brew method; extreme use of extracts, flavorings, and kits. Open some packs, pour it in, stir, and brag about their newest brew. Many home brewers are threatened by all grain brewing and will be quick to direct you elsewhere if you mention it. It's a generational thing. If they can't cook a gourmet meal they can't brew traditional quality beer. But... then again, some people think peanut butter or maple bacon flavored beer is really good stuff. LOL

 

Welcome to HBT Barry. Don't hold back.

 

I keep forgetting about all those baby boomers starting up breweries nowadays.

 

Here's another different way of thinking... mash temperatures don't make as big a difference as we think. So I mash everything around 150°+-. Therefore I never have strike water as high as 170-180°. My strike temps are right around the upper limit of what has always been thought of as the upper limit for mashing. So even if there is some reaction at dough-in it should be negligible at 160° vs 180°... right?

 

You seem to be trying to solve a problem that isn't there. Most strike temps may not be in the optimal range of alpha and beta-amylase, but they will not be denatured at those temperatures. A few seconds at a higher temp won't hurt them. It could be too high for beta, but I don't think I've ever heard of conversion issues related to strike water if it's properly dialed in. I'm doubtful that a few seconds above 160 degrees F is enough to denature much, if any beta.

I'd also bet if you did this using fully modified grain it will be detrimental to your beer. You'll hit beta-glucanase and protease temperatures on your way to your mash temperature, and these enzymes have already been activated and allowed to work to the desirable level during modification. You want some proteins and beta-glucans in your wort for body and foam, and you could get rid of too much. Anecdotally, I once mashed in and left the house for several hours to do some errands, and the temperature went from around 150 to 136 when I got back. Protease wouldn't have completely denatured at 150 and 136 is in the optimal range. The beer had very, very little body. No proof that the lower temps caused it, but it was the only thing different about my process for that beer.

 

yeah but, consider that baby boomers have a history of decades of available good beer, and they can afford the best, so they would/should attain for quality in their brewing.

 

Are you trying to say that only baby boomers know good beer and all the younger generations are idiots lacking fine tastes who can’t cook or brew and only brew extract? I’m confused as to why this is in this thread.

 

Gen Xers and millennials make up most of the active brewing community nowadays (professional and homebrew). There's no generational thing about using extracts and brewing kits, and I'm really unsure of where this idea came from. Everyone I've met who has dabbled in homebrew has moved on from extract, or has just started.

Also, the brewing industry is trendy and there's a lot of weird stuff going on, but classic styles are far from dead. I say that as a millennial who loves classic styles more than anything.

 

This thread is “all grain mashing”. In speaking directly to Dolmetscher007 I was making a contrast of all-grain enthusiasts to the average kit brewers. I’ve seen legitimate questions on here get shot down by those who are either just a know-it-all, rude, or threatened by any thinking outside the box/kit. Just wanted to warn him that some are overly sensitive. Are you a moderator, did I break a rule?

 

Well said. I should have put the "it's a generational thing" in quotes. It was what my granddad said when he was perplexed by 'the younger generation", who at the time was my generation. Some of the best beer I've had in recent years was made by brewery owners in their late twenties and thirties. BTW, I didn't use labels such as "Gen Xers and millennials". Nor did I say "all" or "only". Sorry if anyone took what I said to heart as a personal attack.

 

No worries. I guess it seemed like the implication was that millennial brewers weren't creating quality beer, I always get irked at people making sweeping criticisms of millennials, or really any sort of generational criticism. They're all not as different as some people make them out to be.

 

No, I’m not a moderator and I’m pretty sure no rules were broken. I was just a bit confused by your comments and how they fit into an 8 month old thread about strike temps. Actually I’m honestly still not clear what your point was with the generational comment. I’ve seen the youngest to the eldest brewing both extract and all grain. Some never touched extract, some never plan to go to all grain. Different strokes for different folks, at the end of the day it’s all beer right?

 

Old thread, but I also use the "underlet" method in my mash tun. I really hate having to hold a heavy bucket steady with one hand and shoulder and stir with the other, so I dump the (room temp) grain in the tun and add the strike water from the bottom. Once it's at a level where it's over the grain, I start stirring, and keep on until I'm at the level I need to be. Strike water has to be a little hotter (around 170) for it to work right, but it always does and my old shoulders thank me.

 

I get more or less the same results, the other way around. I put the 168-170 degree water in the mash tun, dump in all the grain then stir. Easy peasy.