Extra 15 minutes of mash?

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jpsloan

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Ok, so. I've done three AG brews so far. The first and third were Biermuncher's Centennial Blonde ale. Both times, I ended up with a final gravity of 1.032, which is about 16 points less than what Brewsmith says it ought to be (1.048). The recipe is 8-3/4lbs of grain, with a 11 qt mash at 150degrees, and a 4.5 gallon sparge @ 180degrees, split in half.

Forgiving the crush that I get from AHS, I pretty much follow the double batch sparge method with no mash out. I went through my settings in Brewsmith, and I found one key, salient point that I had missed both times.

The program asks for a 75 minute mash. I've only been giving it a solid hour before vorlauf.

So, here's my question: is that last 15 minutes of mash enough to make up for at least most of my final gravity sucktitude? Or is it only a minor thing, and I really need to contend with the crush (somehow), or adjust the sparge?
 
Are you talking about final gravities after fermentation, or original gravity before fermentation?

I am thinking it is OG. So essentially you are not reaching the same efficiency that BM has his recipes set to. I can get 70% eff. with the crush from AHS. How are sure of your thermometer calibration?
 
Do a starch test. Take some of the wort and add some iodine to it, in a separate container. If it turns black, let it go for another 10 minutes and repeat. I do a 90 minute mash with all my batches and my gravity is close (a couple points either way) to what is called for. How confident are you in the hydrometer reading? Are you correcting for temperature when you calculate the hydrometer reading?
 
It is really difficult to know what the problem is without seeing your method.
Generally, 15 extra minutes of mashing won't increase your efficiency. Actually, there is some debate as to whether a 60 minute mash is even required. I've had success with mashes shorter than 40min.

Here is a few factors that might be affecting you:
1. The recipe seems to assumes ~70% efficiency, which is pretty good, and only really achievable if you are continuously sparging. I personally prefer batch sparging, but have never gotten above 65% efficiency from a batch sparge.
But your efficiency seems to be more like 50%.
2. Maybe your crush isn't very good
3. Do you mix your mash well to assure that you have no dry pockets
4. Hydrometer readings could also be a bit off.
5. Does your final volume match what the program gives you?

It is still really surprising that you would be low by 16 gravity points, but maybe the combination of a few of these factors is getting you there.

Also, why are you using 180degree sparge water. With batch sparging you don't worry about extracting tannins, as much as in continuous sparging but at 180degrees you might actually extract some. Plus if you are not mashing out you aren't really denaturing that enzymes anyway, so why risk adding 180degree water to your grainbed.
 
Ack... yes. I mean Original Gravity after boil. I'm a dink.

I have never calibrated my thermometer, and I think that would be worthwhile. I appear to be achieving my temperatures as predicted by Brewsmith, so I haven't had any red flags that indicated I was missing them, but I will look into that.

I will also do a check on my hydrometer... I have an extra (came with the wine kit), which makes this easy.

I don't have any real control over crush. I haven't seen several thread screaming at Forrest to improve on his mill, so I figure others have done well with it so far. I do give the grist a thorough stirring at dough-in, and then again prior to the first vorlauf... and each time I add the sparge water. However, there is a possibility that I'm shying off the bottom of the MLT for fear of knocking loose my braid (it's just kind of sleeved onto the vinyl tube since I'm a dink, and can't figure a decent way to attach it to the barb with hose clamps). So, it's a possibility that there's sugars down there at the very bottom that could be stirred into suspension better.

So, the extra fifteen minutes might not be a significant factor? I did a Witbier for my second batch, but I was in a little stormcloud of chaos and managed to not check the gravity on that one.
 
What temperature are you taking your hydrometer reading at? And what is you hydrometer calibrated to 60degrees or perhaps 68? You can use a site like this:
http://www.myhomebrew.com/hc0.html
to correct it.
A scratch test may be useful. After three all grain batches the best approach is to try again. It can take a while to learn your system.
 
Unless you are working with poor mashing conditions, you should not need a 75 minute mash to reach your OG. The only difference you should see between a 65 and 70 minute mash there should be for fermentability.

That said, if you are working with poor mashing conditions, then you might need that other 15 minutes. The recipe probably says to go 75 minutes "just to be sure." Like avid said, the only way you know what is in your mash tun is to do an iodine test (you can use iodophor).


TL
 
Alrighty. Thanks for the replies, guys. I have some equipment calibration checking to do. And Sunday, I'll be doing another batch, and I'll do an iodine test to see if I'm converting. I'll also work towards measuring volumes and gravities as I go this time, in an effort to quantify what's happening more precisely.
 
1. The recipe seems to assumes ~70% efficiency, which is pretty good, and only really achievable if you are continuously sparging. I personally prefer batch sparging, but have never gotten above 65% efficiency from a batch sparge.
But your efficiency seems to be more like 50%.

I disagree with that. I have done two AG's and have gotten 82% and 78% while batch sparging. I would say that more sparge water, better mixing. Hitting strike and mash temps are all more important to look at. Your water-grain ratio looks to be ok, but I always shoot for ~ 1.5 quarts/lb of grain. But I don't know how much that would change your efficiency.
 
I would recommend checking for starch conversion. It is very easy to do and will prevent you from draining the mash before it is ready, which I would assume will increase efficiency.
Last time I mashed it took 75 minutes at 152 degrees for conversion (my spoon wasn't big enough to get a very good stir). If you don't have iodine (easy to find at drugstore/grocery store) make sure the wort has an iridium shine to it before draining.

My efficiency was 77% and I batch sparge in a 48 quart cooler with a double sparge.
 
1. The recipe seems to assumes ~70% efficiency, which is pretty good, and only really achievable if you are continuously sparging. I personally prefer batch sparging, but have never gotten above 65% efficiency from a batch sparge.

Simply not true. Since the purchase of my Barley crusher I have consistently hit 80%+. Before I was at a steady 65 to 70%, both with a split batch sparge.
 
Does everyone talk about mash efficiency or brewhouse?

I tend to calculate my efficiency from what I get into my fermenters, which I think would be my brewhouse. To get my mash efficiency I should take a pre-boil hydrometer sample and the amount of liquid in my boil pot right?
 
That is correct. You take those points from the reading and multiply by the gallons collected. You then divide that by the total possible points from your grain. (For your grain you multiply by the number of # you used.)

EX. You get at 1.046 @ 6 gallons. 46*6=276

Add your numbers up using the ppg for each grain. 11# 2-row at 1.036 11*36=396


You take 276/396=.69 or 69%
 
Thanks! I'll have to do that to see what sort of mash efficiency I'm getting as that seems to be what everyone uses as their reference point (I was feeling bad about my 69% brewhouse efficiency on the last brew)

As for the original post. I have always found Austin HomeBrew Supply's crush to be just fine for me. You may have issues with hitting your mash temps. Also when you sparge try using water near 180 degrees to make the sugars more soluble.
 
By the way, most brewing software will calculate it for you. Just check the box that says you took your reading from the brew pot.
 
I think the stirring may be your issue. I'm pretty new to AG myself and I just added 15 points to my brewhouse efficiency (70 to 85) by adding a mash out and stirring more throughly. I also used 5.2 stabilizer for the first time in this batch. That might have helped as well.

Just like you, I was stirring very gently toward the bottom of my cooler tun for fear of hooking and disconnecting my circular braid. What I do now is kind of scoop the more compacted grain with my long handle spoon from the bottom up to the top where I can stir it in.
 
I think the stirring may be your issue. I'm pretty new to AG myself and I just added 15 points to my brewhouse efficiency (70 to 85) by adding a mash out and stirring more throughly. I also used 5.2 stabilizer for the first time in this batch. That might have helped as well.

Just like you, I was stirring very gently toward the bottom of my cooler tun for fear of hooking and disconnecting my circular braid. What I do now is kind of scoop the more compacted grain with my long handle spoon from the bottom up to the top where I can stir it in.
I use 5.2PH Stabalizer and do a 2 hour mash. I routinely hit over 90%. This was even with my LHBS crushed grains. The process is detailed in my signature.

A 2 hour mash works for me, but I might be scaling back now that I have a Barley Crusher. It's a lot longer than most people go, but it ensures you get the most out of your grain.
 
I think the stirring may be your issue. I'm pretty new to AG myself and I just added 15 points to my brewhouse efficiency (70 to 85) by adding a mash out and stirring more throughly. I also used 5.2 stabilizer for the first time in this batch. That might have helped as well.

Just like you, I was stirring very gently toward the bottom of my cooler tun for fear of hooking and disconnecting my circular braid. What I do now is kind of scoop the more compacted grain with my long handle spoon from the bottom up to the top where I can stir it in.

You know, I have this nagging suspicion that you might be right. And if you are, then I would feel at the same time embarrassed and relieved. Right now, I have a circular braid setup, with the S.S. braid looping to a brass T fitting. Problem is, though, that the T simply sleeves around the short length of vinyl tubing going to the barb. This can be simply pulled off, which I do to clean it. But this makes me sheepish when stirring the bottom.

I'm wondering if I shouldn't try just pulling it off, reworking it into a straight braid that I can hose clamp down, and put a length of perforated vinyl tube inside the braid for rigidity. Perhaps if I feel more confident when stirring, I'll get more into suspension.

After I check the thermometers and the hydrometer, I'll give that a shot. Then... I might give that 5.2 Stabilizer a go.
 
I'm wondering if I shouldn't try just pulling it off, reworking it into a straight braid that I can hose clamp down, and put a length of perforated vinyl tube inside the braid for rigidity. Perhaps if I feel more confident when stirring, I'll get more into suspension.
A stainless braid can take a bit of abuse. Don't worry about hitting it a few times. I don't reinforce mine with vinyl. It seems fine after 4 AG batches.
 
My concern has more to do with pulling it off of the barb, really... and draining directly from grain bed into the valve. Which I suppose wouldn't be the end of the world, as long as I get a decent vorlauf (I vorlauf 2 quarts each time I drain).
 
The first step is to accept your current efficiency and factor that into your next batches…until you can start making improvements. In most cases, we’re only talking another pound or two of grain to get your desired OG.

I picked up about 8 points in efficiency when I moved from a standard (double) batch sparge to a hybrid fly sparge.

The process is very similar, but the results are quite different:

Do everything you normally do, up until it’s time to sparge.
  • Stir your mash thoroughly.
  • Go ahead and vorlauf several quarts to clear your wort (make sure to do this very slowly as to not create suction and develop a stuck sparge).
  • Heat your sparge water to 185 degrees.
  • Open your valve slightly and begin draining slowly to your kettle.
  • Begin ladling in your sparge water very slowly and gently to the top of your mash water.
  • Only ladle as much water as is required to keep 2-3 inches of water over the top of the grain bed.
(Many people will use a plate or something to prevent the water from disturbing the grain bed).
  • Continue slowly. If you need to pause to heat more water…simply shut off your valve.
  • Sparge until you hit your desired pre-boil volume.

See if this helps. The idea is that instead of stirring up your grain bed several times and re-suspending sugar throughout the bed…you are slowly adding hot water that acts as a squeegee and pushed the sugar water down through the grain bed…plunger style.
 
The idea is that instead of stirring up your grain bed several times and re-suspending sugar throughout the bed…you are slowly adding hot water that acts as a squeegee and pushed the sugar water down through the grain bed…plunger style.

In this case, if I understand correctly, the circular braid configuration would be preferrable? What I might do is to try this ladle-fly sparge on my next batch, and if it doesn't agree with me, I might then try reworking my braid and going back to batch sparging.

Also... thanks for all the recipes I've been brewing! They're all hits so far!
 
One other thing that might be affecting your effiency... and this might solve two problems for you is this. If your braid looks like this...

198340475397_0_0.jpg


... half of your grainbed is probably rinsing better than the other half because the liquid will naturally want to take the path of least resistance to the drain meaning that a lot of the liquid is running down the side of the mash tun that is closest to the drain. This is what I rigged up. You want to use some high temp hose to get you a little extension to get the braid into the center of the tun to allow for more even draining. This may give you two spots to get a good clamp as well.

5923-100_0404.jpg


These are not actually my images I found them in the "equipment gallery" (my god this forum is awesome). I used more conventional hose clamps on mine. This seems to use some kind of nut to fasten them. If you would like I can snap a quick pic of my setup when I get home from work later today.
 
In the way of update:

I brewed a new batch yesterday, and did an iodine test on the first runnings. I appear to have a full conversion.

I ended up swapping out my braid with a straight one, hose clamping it to the barb of the valve, and stirring the bottom of the MLT like an insane person.

This wasn't the same recipe, so the results aren't entirely analogous. According to Beersmith, this recipe's OG should have been around 1.065. I ended up with 1.052. That's pretty close to the same differential, despite being a higher gravity. Which could mean that I made modest improvements, or that there's something wrong with the way I'm measuring the gravity.

In any event, I feel good about my method, and until I can make major changes (like getting my own mill), I'm just going to start upping my base grains to improve on the gravity, and start R'ing, DW'in, and most of all, HAHB'ing. :ban:
 
If you are measuring the wort preboil then your OG will be different then what it will be after hops and boil occur. Remember you boil off water making it more concentrated, so a lower OG preboil means nothing. All you can do is calculate your efficiency off of that.
 
Uh... hold the phone...

I just double-checked BierMuncher's recipe post, and he's got it listed as an anticipated gravity of 1.051.

So...

Nevermind.

:rockin:
 
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