Controlling Attenuation Through Mash Times

[ArcLight]

Where did he say that it was beneficial to introduce O2 during the mash?

>>In fact, some argue that upstream oxidation is actually beneficial to beer flavor stability because the oxidized compounds are created earlier (rather than later) and removed as part of the hot/cold break and any remaining compounds are consumed by the yeast.

For the "oxidized compounds" (whatever that means) to be removed by the hot break, they have to be created either during the mash (adding Oxygen) or right after mashing, while heating to boiling.

Also - the upstream Oxuidation example the original poster cited by Bud

>>Consider Budweiser - they force sterile air through the wort after the boil is complete to remove undesirable volatile compounds (e.g., DMS, SMM, etc.). Clearly, this creates oxidation.

Its normal (necessary ) to Oxygenate wort after boiling because it's deoxygenated and the Oxygen is needed by the yeast initially to strengthen their cell walls in preparation for budding. Do they first cool teh wort down? (I assume so)

So my original question remains -
Can someone provide links to research that shows its a good idea to Oxygenate hot wort, or Oxygenate the mash?

The reason I ask is based on what I have read it's not desirable to introduce Oxygen at any time prior to the wort being cooled.

 

[TheZymurgist]

I have a couple questions. First is there any down sides to doing a longer mash and having the mash temp drop below 148 F?

Secondly,



I see how these would affect the beer in the ways you stated, but how could you achieve the same O.G. with both these methods? I feel like you will always have a greater O.G. with the thick mash. Would you have to boil the thin mash longer to achieve the O.G., but wouldnt this also affect the fermentability?

Thanks,
Chad

If you adjust the amount of sparge water, you'll end up with the same boil volume, and therefore the same OG. With a thick mash, you use more sparge water since there is less water in the mash, with a thin mash, you use less sparge water. No need to boil longer to achieve the OG since the volumes are the same.

Many people do see an increase in efficiency (sugar extraction) with higher sparge volumes, so this would cause an increase in your OG, but not because of the boil volumes.

 

[chad_]

If you adjust the amount of sparge water, you'll end up with the same boil volume, and therefore the same OG. With a thick mash, you use more sparge water since there is less water in the mash, with a thin mash, you use less sparge water. No need to boil longer to achieve the OG since the volumes are the same.

Many people do see an increase in efficiency (sugar extraction) with higher sparge volumes, so this would cause an increase in your OG, but not because of the boil volumes.

Thank you, that is exactly what I was looking for!

 

[Genuine]

From my own personal experience, most of my beers have finished pretty low and I usually do a mash of 1.25 Quarts/lb of grain and I batch sparge using 190 degree water to get the mash to 170 degrees. Since getting a refractometer to keep watch on my pre-boil gravity, I can check during the boil and end up hitting my OG. I'll be checking on my FG for my amber ale tonight so I can report back on this current batch did.

 

[LovesIPA]

Don't you risk tannin extraction from sparging with water that hot?

 

[dantodd]

Don't you risk tannin extraction from sparging with water that hot?

You won't get tannin extraction just by sparging at 170 though it is at the top of the recommended range. IMO over sparging is a much greater risk than hotter water.

 

[babski]

Wow! I'm ready to start doing AG batches, or so I thought, but after reading this thread I'm really confused! Subscribed because I don't know half of what I thought I knew. Can anyone reccommend a good book that explains all this in detal?

 

[dantodd]

"How to Brew" by John Palmer is the best resource in one place for all your basic brewing info. You can read the first edition on his website but you should definitely buy the book as it is much easier to read, it is updated and it won't short out if you splash a little wort on it.

As for All Grain brewing. Just do it.

Pick a recipe that is pretty flexible if you miss your OG. Be sure to calculate your efficiency so that you can get closer on your next batch. When you change things change one thing at a time so you can tell what caused any change you see.

It's just like homebrewing the biggest thing holding you back is fear of doing something wrong. But, just like extract, if you keep things clean and keep your fermentation temp under control you'll end up with good beer.

 

[TheZymurgist]

Wow! I'm ready to start doing AG batches, or so I thought, but after reading this thread I'm really confused! Subscribed because I don't know half of what I thought I knew. Can anyone reccommend a good book that explains all this in detal?

A lot of this is good to know in theory, but isn't necessary or essential for all-grain brewing. Many people (I would assume most) will do a 60 minute mash regardless of the temperature. I'll usually extend my mashes under 152 or so for 30 minutes, unless I'm pressed for time or just feeling lazy. Can't say I've ever really noticed a difference, or one that I can pinpoint to mash time.

I just brewed a porter on Saturday where a one hour mash turned into three hours because I couldn't get my burner working. This is one that regularly finishes at 1.018 to 1.020, with an OG of 1.055. I'll be curious to see if the extra time helps attenuation at all.

 

[vereto]

>>In fact, some argue that upstream oxidation is actually beneficial to beer flavor stability because the oxidized compounds are created earlier (rather than later) and removed as part of the hot/cold break and any remaining compounds are consumed by the yeast.

For the "oxidized compounds" (whatever that means) to be removed by the hot break, they have to be created either during the mash (adding Oxygen) or right after mashing, while heating to boiling.

Also - the upstream Oxuidation example the original poster cited by Bud

>>Consider Budweiser - they force sterile air through the wort after the boil is complete to remove undesirable volatile compounds (e.g., DMS, SMM, etc.). Clearly, this creates oxidation.

Its normal (necessary ) to Oxygenate wort after boiling because it's deoxygenated and the Oxygen is needed by the yeast initially to strengthen their cell walls in preparation for budding. Do they first cool teh wort down? (I assume so)

So my original question remains -
Can someone provide links to research that shows its a good idea to Oxygenate hot wort, or Oxygenate the mash?

The reason I ask is based on what I have read it's not desirable to introduce Oxygen at any time prior to the wort being cooled.

Quoting for attention. I am also very interested in an answer to your question.

 

[Jablestein]

Learning new things everyday and I'm glad I found this thread. Just wanted to clarify a few things for my understanding...

I've only recently started AG brewing with 4-5 under my belt but I've not been extremely happy with the results. I have some kinks to work out in my mashing process, specifically related to controlling temps.

A friend of mine just recently introduced me to the concept of drier/sweeter brews based on target mashing temps, but based on what I'm reading here mash times also play into this as well. So if I understand it correctly higher temps and shorter mash times equate to more un-fermentable sugars and therefore a sweeter tasting beer (less attenuation if I'm using the lingo correctly), where lower temperatures and longer mash times equate to more fermentable sugars and therefore a drier tasting beer (more attenuation?).

Is this just an advanced technique? I assume someone like myself should focus on hitting the proper temps before worrying about extending/decreasing mash time.

Lower attenuation also sounds like a potentially bad thing if you're not careful. Couldn't you end up with a bad batch that fails to ferment at all?

I'm curious how this plays into recipes and processes for brewing stronger IPAs. As I understand it stronger hop bills require higher grain bills to balance bitter flavors with maltier ones. Should these beers be brewed at shorter length and higher temps as well?

 

[pjj2ba]

........... So if I understand it correctly higher temps and shorter mash times equate to more un-fermentable sugars and therefore a sweeter tasting beer (less attenuation if I'm using the lingo correctly), where lower temperatures and longer mash times equate to more fermentable sugars and therefore a drier tasting beer (more attenuation?).

Is this just an advanced technique? I assume someone like myself should focus on hitting the proper temps before worrying about extending/decreasing mash time.
................

Sweetness is mostly dependent on the grain bill, not the mashing regime. The mashing regime affects the body. A hotter, short mash will result in a beer with more BODY. Sweetness in a beer is largely from the grains themselves. During the kilning process the maillard reaction is occurring. This results in a darkening of the malt and also produces unfermentable compounds that taste sweet. Generally the darker the malt the more sweetness it provides - roasting is something else altogether. Body and sweetness often do go hand in hand (and body contributes to perceived sweetness), but it is possible to brew a rich, full bodied, high FG beer, that is not sweet at all.

Balance is complicated. There is the BU:GU guidelines for beer styles (bittering unit/gravity unit ratio). This is very simplified though but is still a good starting off point. It gets more complicated.

Bitter and sweet need to be balanced - these are perceived on your tongue by the taste buds. Body perception is much more complex, and also helps to offset bitterness (but not like sweet does). The higher the FG, the better it will offset the bitterness, but you can achieve a similar bitterness offset in a beer with a lower FG by including some ingredients that provide sweetness.

And then there are some funky Belgian yeasts out there that I would swear make some kind of compound that tastes sweet. I know there are certain proteins that taste sweet, and of course more simpler natural products like stevia. I like the White labs Saison II yeast. It is a monster and will chew through anything. I routinely have beers around a FG of 1.005 with this yeast, yet they taste quite sweet - even in a grain bill that is almost all pils malt with just a little wheat added to it. There is some byproduct of fermentation that is responsible for this. I use a similar grain bill for my Kolsch, which tastes and feels nothing like my saison

 

[tootal]

After reading this whole thread I noticed one factor that's missing and that's how well your malt is milled. If you mill the malt to where the endosperm is in 4 pieces and the hulls are left whole you will likely not stick your mash and is good for home brewing. HOWEVER, you will need longer mash times to convert these large pieces of starch to sugars. Since Budweiser was mentioned, they use a three roller system and the endosperm is like talcum powder. They also must use rakes in the lautertuns to keep the "vorlauf", or recirculation, going. This allows shorter mash times which helps save money since you can do more brews per day. So basically, the finer the mill the quicker the mash but for a homebrewer it's much safer to be a bit coarse and just use longer mash times.

Now as far as Budweiser forcing sterile air through the hot wort after the boil causing oxidation well that's not exactly what happens. What they do is they have a tank that's full of tubes. The wort raises up to the height of the tubes and starts running down the sides of the tubes. This unit is called the stripper. The hot air blowing up the tubes "strips" out the DMS etc. It does not however, oxidate the wort. You would think it would but since it's sliding down the sides of the tube it doesn't pick up oxygen but only gives up the volatils.

 

[LovesIPA]

So basically, the finer the mill the quicker the mash but for a homebrewer it's much safer to be a bit coarse and just use longer mash times.

Is this statement about efficiency or about attenuation?

Now as far as Budweiser forcing sterile air through the hot wort after the boil causing oxidation well that's not exactly what happens. What they do is they have a tank that's full of tubes. The wort raises up to the height of the tubes and starts running down the sides of the tubes. This unit is called the stripper. The hot air blowing up the tubes "strips" out the DMS etc. It does not however, oxidate the wort. You would think it would but since it's sliding down the sides of the tube it doesn't pick up oxygen but only gives up the volatils.

The brewing nerd in me wants to know a lot more about this process.

I googled for "budweiser stripper" but couldn't quite find what I was looking for.

 

[tootal]

Efficiency.

As far as the "stripper", only Anheuser Busch and Kirin uses it. When AB started making Kirin beer in LA the Japanese came over to taste it and see the process. They liked it better than theirs. During the process they saw the stripper so AB had one made for them so Kirin uses it in Japan now too.
We use to use a Drop Receiver too. It splashed the wort in a large tank that drained quickly and had sterile CO2 flowing through it to get even more of the volatiles out but the cost and loss of CO2 made it too expensive for Inbev to continue to use.

 

[gometz]

Many people do see an increase in efficiency (sugar extraction) with higher sparge volumes, so this would cause an increase in your OG, but not because of the boil volumes.

I know this is an old post, but this is what I immediately noticed during my last brew. I did a pretty thick mash (about 1 qt/lb) but sparged with enough to get 7 gallons for a 90 minute boil. My OG ended up being 1.060 when I was targeting 1.053. Hopefully the 150*F 60 minute mash means it will dry out a bit more.

 

[gometz]

Sorry to bring this thread back to life, but I figured it would be better to post here than to start a new thread.

I am wondering just how low of a FG you can get by mashing low and long. So for instance a 2 hour mash at 145*F for an imperial IPA or something like that. Could you get a beer with an OG of 1.080 down to 1.010 without using sugar and only using "normal" yeasts?

Another idea I had was to actually start off mashing higher and then drop the temperature. This comes from the fact that the alpha amylase will digest the bigger proteins into sugar which the beta amylase will then convert to fermentable sugars. So my idea would be to do a 30-60 minute rest at 156*F, then drop the temperature down to 145*F for 1-2 hours. If the enzymes cannot survive the higher temperature, could you just add some 6-row since it is rich in enzymes to kick start the beta conversion again?

I am only on my 7th all-grain, but there is so much interesting information and so many tactics that I doubt I will ever learn it all.

 

[grathan]

Good questions. I unfortunately don't have answers because I also wonder the same things. I think picking a particular yeast strain would make the conversation more useful as there are some yeast strains that will take 1.080 down to 1.010 and some that will not.

I like you idea about dropping the temperature. It doesn't get discussed much. I even asked about a few posts earlier in this thread and got no reply. I like the 6-row idea. ALso perhaps splitting the mash into 2 smaller mashes and then combining to let the beta finish off.

Some thoughts on wort fermentability:
You need an accurate thermometer and accurate ph meter.
Thin mash for fermentability. What can your system handle?
Mash ph that favors beta
malster information. You probably don't get a copy of the malsters grain data when you buy grain at lhbs. All grain is different.
yeast nutrients and aeration technique. general yeast health when added to the wort. Amount of yeast pitched.
accurate fermentation temperature controls. Using techniques like rising temperature and ferementing at higher temps.

There was a podcast or something by Mitch Steele? some guy that worked at Budweiser and Sierra Nevada. He talks about getting IPAs fermented down low.


You also need to understand Why you want to get that low. And also how it effects things like mouthfeel and flavor and possibly exposing flaws in your beer as well.

 

[gometz]

Good questions. I unfortunately don't have answers because I also wonder the same things. I think picking a particular yeast strain would make the conversation more useful as there are some yeast strains that will take 1.080 down to 1.010 and some that will not.

I was thinking WLP007 or WLP090 might do the trick, but mashing would be important to get the correct amount of fermentables into the wort.

This is something I am thinking about while I wait for my fermenters to open up again (4 more weeks! not sure how I am going to make it!). I have some "fresh"* hops that I want to use to finish an imperial IPA.

*vacuum sealed and frozen 1 day after harvest. 6 oz of Mosaic and Cascade

 

[pjj2ba]

..........
Another idea I had was to actually start off mashing higher and then drop the temperature. This comes from the fact that the alpha amylase will digest the bigger proteins into sugar which the beta amylase will then convert to fermentable sugars. So my idea would be to do a 30-60 minute rest at 156*F, then drop the temperature down to 145*F for 1-2 hours. If the enzymes cannot survive the higher temperature, could you just add some 6-row since it is rich in enzymes to kick start the beta conversion again?

The temperature drop doesn't work. Once you heat up above where beta-amylase is happy it denatures. For most proteins, this is the end of the road and cooling back down does not restore activity, that would be like making a hard boiled egg back into an un-boiled egg.

If you want a low FG, then mashing cooler and longer will do that. If you want a low FG, but don't want it too thin tasting there are a couple of things you can do. Split the mash and mash most of it at 145-147, and have another small portion that you mash high. Combine the two at the boil stage. You also could just hold back some of the malt and add it toward the end of the mash - this is tricky as it could result in starch haze. If you don't care about that, then it is a good technique to use. If you want it thin, then you can add some crushed up beano, typically to cooled wort. The enzymes in beano will break down the last of the dextrins that the amylases cannot attack.

 

[grathan]

I wonder if starting at 152* instead of 156* would allow much more of the beta to survive? Any information on denaturing amounts at specific temperatures?

 

[d_striker]

I got a pump for my system and now have a direct fire RIMS setup. I did a step mash with a 30 minute rest at 133. It took 15 minutes to step up to 151 which is when I then started the clock for a 60 minute sach rest. Total mash time was 105 minutes.

My efficiency was through the roof at 93%! My mash efficiency is typically VERY consistent at about 80% prior to the new RIMS process. Grain bill was about 94% 2-row, 5% honey malt, and 1% flaked barley.

This beer was supposed to be a Blonde ale but I overshot my OG beyond what I was anticipating. OG was 1.057 after a 60 minute boil. Pitched an estimated 250B cells of WLP090 via multi-step starter. Gravity was 1.020 after 2 days, 1.010 after 5 days, and 1.008 after 8 days. The crazy thing is that it's still going! It's slowed down noticeably but it's still emitting CO2 and doing the yeast blob rise thing.

I ferment in a temperature controlled chamber. First two days were at 65-66F. Then let free rise to 68F. After I took the reading at 1.010, I let free rise to 69-70F. Temp has dropped to about 68F as active fermentation is for the most part done.

So far, it's attenuated 86%. I usually get about 80% attenuation with my process for this style. I was initially planning on cold crashing by now but I'm letting this thing ride as I want a drier beer. The sample I took tonight still had a noticeable sweet malt flavor which surprised me. It may be the honey malt. I think that it will drop another point or two over the next few days.

 

[brewmcq]

Any update on this, d_striker?

 

[d_striker]

Any update on this, d_striker?

I finally pulled the plug on fermentation after gravity hit 1.007. Beer tastes dry up front with a slight malt finish.

 

[Robar]

I just want to say thanks for this thread. This has really shed a lot of light on an area where my brewing knowledge was pretty scant.

Thanks to BierMuncher and all other contributors. Even those asking questions have helped a lot because it brings forth the wisdom being shared here. nestar:nestar:nestar:

 

[joety]

I got a pump for my system and now have a direct fire RIMS setup. I did a step mash with a 30 minute rest at 133. It took 15 minutes to step up to 151 which is when I then started the clock for a 60 minute sach rest. Total mash time was 105 minutes.

My efficiency was through the roof at 93%! My mash efficiency is typically VERY consistent at about 80% prior to the new RIMS process.

I was getting very high efficiencies on my new RIMS at first as well but I had bad issues with tannin extraction. I made a number of changes, each one improved the beers and eventually eliminated the tannin off-flavor.

1.) Reduced volume of sparge water (with smaller beers I add fresh water to the boil to hit my volumes now) and monitor runoff every minute with a refractometer
2.) Slowed down the speed of the recirculation. You will find this makes controlling the temp more difficult but I believe it was one of my biggest contributors to tannins.
3.) Use RO water from local grocer. I have three 7 gallon water containers I will up for about 30 cents/gallon.

My efficiency is no longer ~ 90%, it has dropped to about 80 to 85, but the beer tastes so much better. I am sure I could still tweak it to get higher efficiencies without tannins, but grain is cheap and my time isn't.

 

[grathan]

Did you mess with sparge ph at all?

 

[d_striker]

Did you mess with sparge ph at all?

I personally acidify my sparge water with lactic acid. I do not have any problems with tannin extraction whatsoever.

 

[d_striker]

I was getting very high efficiencies on my new RIMS at first as well but I had bad issues with tannin extraction. I made a number of changes, each one improved the beers and eventually eliminated the tannin off-flavor.

1.) Reduced volume of sparge water (with smaller beers I add fresh water to the boil to hit my volumes now) and monitor runoff every minute with a refractometer
2.) Slowed down the speed of the recirculation. You will find this makes controlling the temp more difficult but I believe it was one of my biggest contributors to tannins.
3.) Use RO water from local grocer. I have three 7 gallon water containers I will up for about 30 cents/gallon.

My efficiency is no longer ~ 90%, it has dropped to about 80 to 85, but the beer tastes so much better. I am sure I could still tweak it to get higher efficiencies without tannins, but grain is cheap and my time isn't.

My sparge process is still the same as it has been for years. Nothing has changed in that regard.

 

[joety]

My sparge process is still the same as it has been for years. Nothing has changed in that regard.

Understood, I was just inquiring as the RIMS process is so efficient in extracting sugars that is it much easier to oversparge creating ph issue and tannin extraction.