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colorolo

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I am in need of help with my efficiency. I've read previous threads, took the advice, but am still having nightmare-ish efficiency problems. So far, I have done 2 all grain batches after a dozen or so extract brews.

My equipment:
I have a five gallon circular cooler from Home Depot that I converted into a mash tun with a stainless steel braided hose.

The recipe:

3.5 lbs. 2-row
0.5 lbs. crystal 20L
0.75 lbs. vienna
0.25 lbs. cara-pils

My process:
Heat the water to the temperature indicated by BeerSmith (at 1.25qts/lb). My last batch, for example, was a two gallon batch that I mashed at 152 F. The strike water temp was 165F.

I poured in the water, let it sit for a few minutes to warm up the cooler, and then added the grains. I stirred, confirmed it was at the correct mash temp, and sealed. I mashed for 60 minutes, stirring every 15 minutes.

After 60 minutes, I stirred again, and drained (collecting first few pints and recirculating). The gravity of the first runnings was 1.060.

I then added the batch sparge water (168F), stirred again, and again collected the first few pints and recirculated. Then I drained. The pre-boil gravity of the whole batch was 1.032.

The expected OG after boiling was 1.065. I ended up with 1.040. BeerSmith calculated my efficiency at 48%.

The only thing I can think of is the grain crush at my LHBS is not good. But I inspected the grains and everything seemed to be properly crushed (but what do I know).

Any insight would be appreciated. Thanks!
 
Can you explain how you are taking gravity readings?

Hydrometer or refractometer? At what temperature?
 
Can you explain how you are taking gravity readings?

Hydrometer or refractometer? At what temperature?

I am taking gravity readings with a refractomerter. I placed the wort into a ceramic mug to cool down for 5 minutes to ambient temp (70 F) then took the readings.
 
I am taking gravity readings with a refractomerter. I placed the wort into a ceramic mug to cool down for 5 minutes to ambient temp (70 F) then took the readings.

Have you calibrated the refractometer in distilled water and verified it's readings with a hydrometer? There could likely be other issues but with very weird readings it's usually the first place to start.

LHBS crushes are notoriously "safe" (i.e. no stuck sparge) but not usually 50% safe. Maybe 60s.
 
Have you calibrated the refractometer in distilled water and verified it's readings with a hydrometer? There could likely be other issues but with very weird readings it's usually the first place to start.

LHBS crushes are notoriously "safe" (i.e. no stuck sparge) but not usually 50% safe. Maybe 60s.

I've never calibrated with distilled but have used tap and it shows a perfect1.00. I'll try distilled to see if that has any change.
 
When I do smaller batches my brew house efficiency drops just due to the fact the trub/kettle losses are a significant compared to the batch size. Doing a 2gal batch in a 5gal mash tun would not help either as the dead space loss would be more significant.

You had a huge empty space in your mashtun and most likely your temp dipped if you did not do something to keep the heat in the bottom. If the temp did drop it might take longer for the conversion to complete. If you stirred it every 15min that could have lowered the temp too making the conversion slower again.

I stir the mash just enough to get things mixed well then stop and let it sit for about 5min after adding sparge water before draining. When I drain right away my efficiency drops.

When I plugged your info into beersmith it looks like you might not have added in trub/ketttle losses. If I set the brewhouse efficiency to 75% and set the batch size to 2.5gal to account for trub/kettle loss I get an OG of 1.054, I get 1.067 if I set the batch size to 2gal. I get 75% brew house efficiency on 5gal batches, but my smaller 1-2gal batches get about 65% using a mini 2gal mashtun.

Did you do some trial runs with plain water to get data for boil off losses and temp losses in cooler? Getting that information is helpful in getting beersmith dialed in.
 
When I do smaller batches my brew house efficiency drops just due to the fact the trub/kettle losses are a significant compared to the batch size. Doing a 2gal batch in a 5gal mash tun would not help either as the dead space loss would be more significant.

You had a huge empty space in your mashtun and most likely your temp dipped if you did not do something to keep the heat in the bottom. If the temp did drop it might take longer for the conversion to complete. If you stirred it every 15min that could have lowered the temp too making the conversion slower again.

I stir the mash just enough to get things mixed well then stop and let it sit for about 5min after adding sparge water before draining. When I drain right away my efficiency drops.

When I plugged your info into beersmith it looks like you might not have added in trub/ketttle losses. If I set the brewhouse efficiency to 75% and set the batch size to 2.5gal to account for trub/kettle loss I get an OG of 1.054, I get 1.067 if I set the batch size to 2gal. I get 75% brew house efficiency on 5gal batches, but my smaller 1-2gal batches get about 65% using a mini 2gal mashtun.

Did you do some trial runs with plain water to get data for boil off losses and temp losses in cooler? Getting that information is helpful in getting beersmith dialed in.

Thanks for the thoughts. I did do trial runs and calculated 0.2 gal dead space loss and 0.5 gal/hour evap loss, both of which were plugged into BeerSmith.

I understand from Palmer that having too much "head space" in the mash tun decreases efficiency, but I don't really want to go smaller than a five gallon cooler.
 
How active was your boil to loose only .5gal? I struggle to keep my boil losses down to 1.25gal/hr and still have an active boil. If you are only loosing .5gal/per hour that will reduce the amount of water used to rinse the grain and may leave behind more sugar. I get better efficiency when I do 90min boils as I need to collect more water and get a little extra sugar.

I had the small cooler so it was cheap for me to make a mini mash tun. I store it inside my 5gal mash tun when not in use. You can add foil on top of your grain to keep the temp more stable.
 
How active was your boil to loose only .5gal? I struggle to keep my boil losses down to 1.25gal/hr and still have an active boil. If you are only loosing .5gal/per hour that will reduce the amount of water used to rinse the grain and may leave behind more sugar. I get better efficiency when I do 90min boils as I need to collect more water and get a little extra sugar.

I had the small cooler so it was cheap for me to make a mini mash tun. I store it inside my 5gal mash tun when not in use. You can add foil on top of your grain to keep the temp more stable.

It's a rolling but gentle boil. I think the design of the pot also helps (as it's tall and not a lot of exposed surface area).

I'll try the foil idea. Thanks!
 
You used 5 lbs of grain with a potential sugar yield of about 3.82 lb of sugar (based on generic grain types in the BeerSmith database.) You mashed in with 1.25 qt/lb * 5 lb / 4 qt/gal = 1.5625 gal of water. 1.5625 gal * 8.329 lb/gal = 13.014 lbs of strike water. So, if you converted all the available starch to sugar you would have first running wort that is 3.82/(3.82+13.014) = 22.69% sugar by wt = 22.69°Plato, which works out to about 1.096 SG. Your first running SG was only 1.060, so your starch conversion efficiency was about 60/96 = 62.5%. This is very low. You should be able to get conversion efficiencies of 98% or better. See this post for more information on the calculations.

The rest of your efficiency losses come from not being able to rinse all the sugar that you did create out of the grain, plus any wort volume losses in the MLT or transferring to the fermenter.

You need a combination of finer crush, longer mash, and more mash agitation to make sure you get complete starch conversion. You can't extract sugar that hasn't been created.

Brew on :mug:
 
I am in need of help with my efficiency. I've read previous threads, took the advice, but am still having nightmare-ish efficiency problems. So far, I have done 2 all grain batches after a dozen or so extract brews.

My equipment:
I have a five gallon circular cooler from Home Depot that I converted into a mash tun with a stainless steel braided hose.

The recipe:

3.5 lbs. 2-row
0.5 lbs. crystal 20L
0.75 lbs. vienna
0.25 lbs. cara-pils

My process:
Heat the water to the temperature indicated by BeerSmith (at 1.25qts/lb). My last batch, for example, was a two gallon batch that I mashed at 152 F. The strike water temp was 165F.

I poured in the water, let it sit for a few minutes to warm up the cooler, and then added the grains. I stirred, confirmed it was at the correct mash temp, and sealed. I mashed for 60 minutes, stirring every 15 minutes.

After 60 minutes, I stirred again, and drained (collecting first few pints and recirculating). The gravity of the first runnings was 1.060.

I then added the batch sparge water (168F), stirred again, and again collected the first few pints and recirculated. Then I drained. The pre-boil gravity of the whole batch was 1.032.

The expected OG after boiling was 1.065. I ended up with 1.040. BeerSmith calculated my efficiency at 48%.

The only thing I can think of is the grain crush at my LHBS is not good. But I inspected the grains and everything seemed to be properly crushed (but what do I know).

Any insight would be appreciated. Thanks!

Crush is always the first suspect. Stirring does nothing for you but lose heat from the mash.
 
You used 5 lbs of grain with a potential sugar yield of about 3.82 lb of sugar (based on generic grain types in the BeerSmith database.) You mashed in with 1.25 qt/lb * 5 lb / 4 qt/gal = 1.5625 gal of water. 1.5625 gal * 8.329 lb/gal = 13.014 lbs of strike water. So, if you converted all the available starch to sugar you would have first running wort that is 3.82/(3.82+13.014) = 22.69% sugar by wt = 22.69°Plato, which works out to about 1.096 SG. Your first running SG was only 1.060, so your starch conversion efficiency was about 60/96 = 62.5%. This is very low. You should be able to get conversion efficiencies of 98% or better. See this post for more information on the calculations.

The rest of your efficiency losses come from not being able to rinse all the sugar that you did create out of the grain, plus any wort volume losses in the MLT or transferring to the fermenter.

You need a combination of finer crush, longer mash, and more mash agitation to make sure you get complete starch conversion. You can't extract sugar that hasn't been created.

Brew on :mug:

This is great information. Thanks! I'm going to get the iodine tester to make sure I'm finished with conversion before I empty.
 
As you are being bombarded by well-meaning blobs of advice, here's another:

As you try to solve this problem; forget, as in totally disregard, any efficiency issues related to what happens after you collect your wort. As soon as the boil kettle flame goes on, your mash efficiency is done. That's where you should be looking. It's your crush, your mash, your sparging, your lautering. Those are the critical steps to focus on.

All of the post-boil losses are variable, and are process or equipment related. These contribute to brewhouse efficiency, which is the overall efficiency of your operation. IMHO it's less useful to a homebrewer to fixate on that number. Mash efficiency is where it's at. Converting and collecting sugars from your grain. Be careful when talking about efficiency with other brewers, and make sure people are referring to mash efficiency rather than brewhouse. It makes a huge difference.

Now back to the bombardment... :)
 
Crush is always the first suspect. Stirring does nothing for you but lose heat from the mash.

Agree that crush is number 1. However, stirring does more than just cause heat loss. In a still mash (no agitation), the different molecules move around by diffusion, which is driven by differences in concentration (concentration gradients) from one point to another. The larger the concentration gradients, the faster things diffuse, and things have to diffuse in order for the saccharification reactions to occur. With no agitation, the concentration gradients smooth out thru space, and diffusion slows down, thus slowing the overall rate of saccharification. Larger grain particles enhance this effect, and slow down saccharification even more. Agitation disturbs the natural concentration gradients, and makes them steeper, thus speeding up diffusion, and therefore saccharification. In a real mash process, there needs to be a balance between lots of different and competing parameters and processes. Sufficient agitation is just one thing that needs to be worked out for a specific set of process conditions.

Many people go to HERMS or RIMS type systems to get mash agitation along with temperature maintenance. It helps, but is by no means necessary.

Brew on :mug:
 
Agree that crush is number 1. However, stirring does more than just cause heat loss. In a still mash (no agitation), the different molecules move around by diffusion, which is driven by differences in concentration (concentration gradients) from one point to another. The larger the concentration gradients, the faster things diffuse, and things have to diffuse in order for the saccharification reactions to occur. With no agitation, the concentration gradients smooth out thru space, and diffusion slows down, thus slowing the overall rate of saccharification. Larger grain particles enhance this effect, and slow down saccharification even more. Agitation disturbs the natural concentration gradients, and makes them steeper, thus speeding up diffusion, and therefore saccharification. In a real mash process, there needs to be a balance between lots of different and competing parameters and processes. Sufficient agitation is just one thing that needs to be worked out for a specific set of process conditions.

Many people go to HERMS or RIMS type systems to get mash agitation along with temperature maintenance. It helps, but is by no means necessary.

Brew on :mug:

FWIW, I get around 83-85% efficiency without stirring. That says to me that stirring isn't necessary and if it is, it's to correct for poor process elsewhere.
 
FWIW, I get around 83-85% efficiency without stirring. That says to me that stirring isn't necessary and if it is, it's to correct for poor process elsewhere.

Are you saying that you don't even stir on mash in? :confused:

I never said stirring was necessary. I was responding to your statement that it had no beneficial effects. I just made a case that agitation could be beneficial in situations where diffusion limitations are causing slow conversion. So yeah, it can compensate for other process limitations.

For the record, I stir aggressively at mash in, and again before run off (bag lift actually), but not during the mash, and also get mid 80's efficiencies. But, I also crush at 0.016" to keep diffusion distances short, and mash thin, so have a lower viscosity mash that allows better diffusion.

Brew on :mug:
 
Are you saying that you don't even stir on mash in? :confused:

I never said stirring was necessary. I was responding to your statement that it had no beneficial effects. I just made a case that agitation could be beneficial in situations where diffusion limitations are causing slow conversion. So yeah, it can compensate for other process limitations.

For the record, I stir aggressively at mash in, and again before run off (bag lift actually), but not during the mash, and also get mid 80's efficiencies. But, I also crush at 0.016" to keep diffusion distances short, and mash thin, so have a lower viscosity mash that allows better diffusion.

Brew on :mug:

No, I stir when I nmash in and when I add sparge water.
 

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