Robobrew regrets?

[WesBrew]

This system boils off, what? .5 gallons in an hour. Are u doing an hour boil? did you set up your brew software with the robobrew profile? I’d think that filling the dead space at bottom+1,5 quarts water per lb of malt would put you at 5 gallons mash water. losing some to grain. Then sparging to a boil volume around 6 gallons would have you around 5.5 to fermenter. Losing some to trub and transfer would net 5 gallons. Rough figuring. There are calculators online to get this exact.

 

[Fidelity101]

I used the Brewfather‘s stock Brewzilla 35L settings for my first batch and ended up with just over 4 gallons of beer. I’ve been adjusting the measurements to try and lock down the exact numbers needed to hit 5 gallons. The last batch was sub 5 gallons when I started with 6.09 gallons of mash water and 1.92 gallons of sparge water. This round I think I went over the mark with 6.09 gallons of mash water and 2.50 gallons of sparge water.

It’s loosing water at the mash step as the mash is set for 60 minutes before even starting to raise the temp from 149F to 170F for mash out. The next mash will start at 154F because of the heat loss during the grain addition and that might be a partial reason for efficiency loss. The brewzilla is then set to 215F for boil and using the 1900 watt element only once boil is reached which keeps a really nice boil. There is more water loss after the boil as it’s taking approximately 20-30 minutes to chill all of that water down to sub 80F. There is not much loss from the transfer from brewzilla to fermzilla because I use the pump to transfer everything it can before dumping the rest in manually. The brew process utilizes a hop container so none of the hops are transferred into the fermzilla.

Because my efficiency is so incredibly low, I’m trying to make small changes to see how I can kick up the gravity readings. PH of the water is adjusted only with 5.2 Stabilizer which has never been tested with my water to see if it’s actually doing enough. My stock water is 7.3 as mentioned above which is definitely not ideal for mashing so I may need to purchase something else to fix that.

For the next batch, I’ll try 6 gallons in the brewzilla and 2 gallons of spare water. That’s 8 total gallons which will hopefully be enough to put 5.5 gallons into the fermzilla. I figure I’ll loose at least 1/2 gallon because of the two trub dumps and loss during the pressure transfer.

I would like to hear what others have used for their brewzilla 35L and fermzilla configuration in terms of total water usage and what efficiencies they’re seeing.

 

[Wayne1]

Lose the 5.2. It does NOTHING.

I use 8.35-8.5 total water. I do not sparge. I mash with the full volume. Boil off, I limit to about .7 gallons an hour. I get about 5.25 gallons into the fermenter. I mill my own grains. I am consistently getting 70%

 

[Fidelity101]

So I'm guessing you have a 65L vs. my 35L brewzilla, correct? Sparging is only needed on mine because it can't hold anymore than 6.09 gallons of water when using 13 pounds of grain.

I have a digiboil AND a brewzilla 35L so it occurred to me that I could be mashing with more than 6 gallons. Instead of 6 gallons in the brewzilla and 2.5 gallons in the digiboil, I could be cycling the water from the digiboil into the brewzilla and brewzilla into the digiboil...basically giving all 8.5 gallons of water a chance to flow through the grain instead of waiting until the end to sparge. Does that make sense and would that improve efficiency?

Also, thanks for the comments on the 5.2 PH stabilizer...I'll toss it. It was a recommendation from my LHBS but that's most likely because he was out of the acids he normally carries. What's the best product to purchase in order to kick the water PH down?

 

[Wayne1]

Email Ward Labs and get their test kit: Ward Labs Test Kit

That will tell you exactly what shape your water is in.

Then use Martin Brungard's Bru'nWater spread sheet to find out what needs to be added.

For lowering pH, I use phosphoric Acid 88%.

Recirculate the strike water within the BrewZilla. Raise the temperature to mash out, lift the mash pipe and then sparge, slowly with the water from the DigiBoil.

Be careful exactly how much water you use and how much you boil off. All of those numbers will come into play, along with your crush, to determine you efficiency.

 

[Fidelity101]

Thank you...I just ordered a kit for $42. I did some PH and mineral testing yesterday and today and I can't believe how different they are! I would have thought the water would be constant over time.

Today I'm getting 290 us/cm at 67F and 7.85PH
Yesterday my solid particle count was closer to 210 us/cm

Until I get the report and provide more accurate measurements, brewfather is telling me to add the following to my next mash:
1.41g Calcium Chloride
3.49g Epsom Salt
4.68g Gypsum
Plus add to Sparge water:
0.49g Calcium Chloride
1.21g Epsom Salt
1.62g Gypsum

I think I'll just try making all of this water in the Brewzilla and then transferring the sparge water over to the digiboil.

 

[Fidelity101]

My Hayburner clone IPA is almost done so I'm a day or two away from making another batch. This last batch used 6.09 gallons of water in the mash tun and 2.5 gallons of sparge water. That put just under 6 gallons of wort into my fermenter. I've dumped the fermzilla jar twice now to get rid of trub and added 2oz of dry hops. I'll loose one more jar after cold crashing as well as a slight amount at the bottom of the fermzilla because of the sediment remaining so that puts me right around 5 gallons of actual beer in my corny keg.

My final gravity was 1.007 so I'm just over 5% alcohol and the taste is exactly what I'm going for. I would really like to increase my efficiency so I'm going to 1.) increase mash in temperature to 154F to account for the loss of heat and then allow the mash temperature to drop to 149F after adding in the 13 pounds of grain. 2.) Ditch that 5.2PH stabilizer and use Phosphoric Acid to get my PH down closer to 5.4. Hopefully these two small adjustments will get my efficiency into the 70% territory.

 

[Fidelity101]

So I'm trying another round. I set water temp to 154F and added 1oz of Phosphoric acid (10%) which brought my mash PH (at the 20 minute mark is when I measured) to 5.5PH. I also added 1ml of Calcium Chloride, 2.3ml of Gypsum and 2.8ml of Epsom Salt to the 8.25 gallons of water before seperating out the sparge water.

After the mash water temp reached 154F, i dropped the temp to 152F and starting mashing in the grains. My mash is now done so I'm raising the temperature of the water to 172F slowly using the 500w element only. (should i be using both elements at this point?)

My plan is to hit 172F, then raise the grains and sparge in the 2.25 gallons of water I have that are sitting in a hot water tank at 172F. Hopefully this process works better than last time as I really want an efficiency north of the 58% I've been getting. I'm still a little confused on the sparge rate because the last few sparges have been fairly quick but I'm reading that it should take 25 minutes or so...much longer than it's taken me in the past. The water flows through the grains much faster and I always thought you were suppose to leave 1/2" of water on top of the grains as they were taking the sparge water. Maybe I'll go slower this time and sparge in the water slowly. The water won't be resting at the top but at least it will take longer and hopefully that translates into more sugar in my wort.

 

[Wayne1]

Did you change the grind on your grains?
That will have the largest effect on your efficiency.
It will need to be changed for the different grains you use.

 

[Fidelity101]

My efficiency this time was 59%. It's so crazy that I'm getting 59% no matter how much effort I put into this. Back when I just stirred in the grains at 149F for 60 minutes and then pulling them out and sparged with 172F water I was getting 59% efficiency. Now that I'm bringing the mash up to 154F before adding grains, dropping temp to 152, soaking for an hour, raising the temperature up to 172F, then raising the grains and sparging with 172F water I'm still getting 59% efficiency.

I did notice that the water (wort) coming out of the grains after I pulled the grains and set them aside, was 1.040. That means I probably still have a lot of sugar left in the grains and I need to figure out how to extract that better.

The grain grind was done by Brewermaster.com as they were milled grains. I did purchase a cereal grinder so maybe that will help me going forward but I'm starting to think the sparging process isn't working as well as it could.

So my wort is 1.041 SG and the small amount of wort left in the grains is 1.040.
Boiling now.

 

[Fidelity101]

I'd really like to see a video of someone actually getting higher efficiency on this brewzilla 35L. Video the entire process so I can see what the heck I'm doing wrong.

 

[Wayne1]

The problem is your pre-milled malt.
You cannot expect to get better efficiency unless you mill the grains yourself, for your system.
Buy a Cereal Killer mill and your efficiency troubles will be lessened.

 

[Fidelity101]

Thank you. When it does finally arrive, what spacing would you recommend for the brewzilla 35L?

Do different grains need to be grinder at a different thickness?

 

[Fidelity101]

So I just watched this video and I noticed that he had time to talk a minute or so and the water was STILL above the grain line when pulling the grain basket. That's 100% not the case for me and the grain milling may very well have something to do with it. When I'm picking out the grain basket, the water goes from being 1" over the grain to not visible within a matter of seconds. If I were to use 2.5 gallons of sparge water while keeping the water 1/2-1" over the grains then the water would be pushed through in about a minute or two. Since people say that process should take 25 minutes or so, I really need to figure out what can be done to keep the water from flowing through the grain so quickly.

 

[Wayne1]

Mill tighter.

I used the same recipe to calibrate my mill to my system. I started at .035". Reduced it to .030" the second batch and improved the efficiency. I am currently at .028" using Rahr Standard 2 row. You may need to use a different gap with a different malt.

A lauter and sparge with a standard lauter tun can take longer. With an all in one, after recirculating for the entire mash, the lauter may be faster.

 

[Fidelity101]

Round 6 and I just don't think it's possible to improve efficiency. I've attached the recipe if anyone wants to look it over.

I've adjusted the water chemistry by testing my water and adding as necessary to get mash PH at 5.4PH as well as adding Epsom Salt, Gypsum and Calcium Chloride. I've milled the grains at 0.030" which is about as small as I can get before it becomes stuck. I mash in at 156F and then lower the temp to 152F even though I want the mash temperature to be 149F. Mash is a solid 60 minutes before I raise the mash out temperature to 172F and sparge with 172F water to reach just under 7 gallons pre-boil. This puts 5.5 gallons of wort into my fermenter so I'll have right around 4.75-5 gallons of finished beer in a week. The beer is always tasty and refreshing but I just can't get the efficiency into the 60's...this last batch was 56%.

If anyone has ideas, I'd love to hear them. I do know that the SG in the mash water after pulling out the grains is still about 1.040. I cant figure out a better way to pull the sugar out without adding more water, which would mean a longer boil time.

If anyone wants to give this recipe a shot (please use the brewzilla 35L for an accurate comparison) and let me know if you get better results than I did

Pre-Sparge SG: 1.058 (I mashed with only 5.25 gallons)
Pre-boil SG: 1.042 (I sparged in until I had 6.9 gallons of wort...approximately 2.5 gallons)
OG: 1.048

 

[Fidelity101]

Round 7. I have no idea what I did differently this time but my efficiency went up a lot.

My OG using the exact same ingredients was 1.055 and I transferred almost 6 gallons into the fermenter. Same steps as above with mash in at 156F and mash temp at 152F for 60 minutes before I started ramping the temperature up to 168F for mash out. I started with 6.1 gallons of water in the mash tun and added 1.9 gallons of sparge water. Grain crush size was 0.030". I got a mash efficiency of 67% according to Brewfather. Huge improvement from the high 50's I've gotten on the last 6 batches.

I also noticed my mash PH was 4.85 about 45 minutes into the mash. Since I want it to be around 5.2, I'm not going to use the 1oz of Phosphoric acid for round 8.

 

[Jag75]

Round 7. I have no idea what I did differently this time but my efficiency went up a lot.

My OG using the exact same ingredients was 1.055 and I transferred almost 6 gallons into the fermenter. Same steps as above with mash in at 156F and mash temp at 152F for 60 minutes before I started ramping the temperature up to 168F for mash out. I started with 6.1 gallons of water in the mash tun and added 1.9 gallons of sparge water. Grain crush size was 0.030". I got a mash efficiency of 67% according to Brewfather. Huge improvement from the high 50's I've gotten on the last 6 batches.

I also noticed my mash PH was 4.85 about 45 minutes into the mash. Since I want it to be around 5.2, I'm not going to use the 1oz of Phosphoric acid for round 8.

Are you using a mash program ? If not you should look into one . I use Bru N Water and really like it . It has my mash ph on point .

 

[Fidelity101]

I used brewfather to create the recipe and set the water. It reported a PH of 5.39 but I used a full 1tsp LESS Gypsum (which shouldn't have made a difference). The PH at mash in was around 5.2 but towards the end it had dropped to 4.85.

I'm still scratching my head as to what caused the mash efficiency to improve so drastically. This is round 7 (67% efficiency) and 1-6 was around 56-58% efficiency. Hopefully I'll be able to figure it out and modify the recipe accordingly because the 58% efficiency was giving me great beer and the ABV was 5.3-5.6% which was perfect. This batch is going to be 6.4%. ABV which is still good but definitely on the high side.

 

[Jag75]

I used brewfather to create the recipe and set the water. It reported a PH of 5.39 but I used a full 1tsp LESS Gypsum (which shouldn't have made a difference). The PH at mash in was around 5.2 but towards the end it had dropped to 4.85.

I'm still scratching my head as to what caused the mash efficiency to improve so drastically. This is round 7 (67% efficiency) and 1-6 was around 56-58% efficiency. Hopefully I'll be able to figure it out and modify the recipe accordingly because the 58% efficiency was giving me great beer and the ABV was 5.3-5.6% which was perfect. This batch is going to be 6.4%. ABV which is still good but definitely on the high side.

It could be your crush . It also could be your process as well . Mixed the mash really good , had a nice sparge . You really should be getting higher efficiency then 67 though. Better efficiency saves you money .

 

[Fidelity101]

Improving the efficiency has been driving me crazy. I know it should be better but I'm just not getting the numbers and I'm getting pretty consistent with the process. I've watched the youtube reviews and brew days with the brewzilla 35L and 65L and I feel that I'm definitely putting more effort into it than they are. I'm adding a hand full of rice hulls to the grain to prevent it from getting stuck. After mashing in and stirring for 5-10 minutes and making sure the grain is completely mixed in, I let the mash sit for 20 minutes before starting the lautering. I'm letting the grain sit a full 60 minutes (more like 75 minutes). Water flow from the lauter is extremely slow. Mash in at 156F, let it drop to 152F with only the 500w element running to hold temp. Wait a full 60-75 minutes before bringing the water temperature up to 168-172F for mash out. Sparging with 172F water. Water chemistry is correct, grain crush is dialed in (0.030")...not sure what else I could be doing. I'm using a full 8 gallons of water and I usually put between 5.5-6 gallons into the fermenter. The liquid coming off the grains continues to drip in until I'm about 206F and then I remove the grains and feed them to my compost bin/chickens.

 

[jschein]

I used brewfather to create the recipe and set the water. It reported a PH of 5.39 but I used a full 1tsp LESS Gypsum (which shouldn't have made a difference). The PH at mash in was around 5.2 but towards the end it had dropped to 4.85.

I'm still scratching my head as to what caused the mash efficiency to improve so drastically. This is round 7 (67% efficiency) and 1-6 was around 56-58% efficiency. Hopefully I'll be able to figure it out and modify the recipe accordingly because the 58% efficiency was giving me great beer and the ABV was 5.3-5.6% which was perfect. This batch is going to be 6.4%. ABV which is still good but definitely on the high side.

In the pdf your mash temp is set to 149 and post boil at 6.41 gallon. this will cause a difference in your results

 

[Fidelity101]

Correct. Setting the mash temp to 149F causes the top of the mash tank to be in the 140-142F range so I've since kicked it up a bit to account for the delta. The post boil of 6.41 gallons has been reduced to 6 gallons (when boiling hot so the cool volume is always a bit less) because I'm not hitting the efficiency and therefor I figured I needed to cut water to make up for the loss of sugars during the conversion. The recipe calls for an OG of 1.070 and I've been routinely hitting 1.046-1.048 although this latest round I was 1.055-1.057. (Refractometer showed 1.057 but the TILT shows 1.055)

 

[Jag75]

I think the robobrew is very similar to the Grainfather that I use . I'm not sure what kind of crush .30 gives you . Do you have a pump that circulates your mash ? Heres what my process is . I use the Grainfather app which is 100% on the money when it comes to water amounts.

My pre boil amount is 1 gallon more then my batch amount . I'm not sure what my crush is because my LHBS does it for me and it's always great . I mash in and mix the grains really well to ensure no dough balls . Then I add the top screen , making sure not to compact it too much. Turn on the pump and recirculate and hold that temp for 60min.

After mash complete I lift up the basket and ramp temp up to boiling temp. I push the top screen down a bit to compact the grain bed so it doesnt channel. It takes me about 45 min to sparge . Once I'm done sparging it's almost to boiling temp .

This process has me in the 80's effeceincy wise 99% of the time

 

[Fidelity101]

Thanks Jag. I'm sure it's something painfully obvious that I'm missing but I'm just not able to figure it out yet. I would really like someone to take this recipe and make a batch and report results. With the brewzilla 35L, at least with mine, I'm getting about 8-10F delta between the reported temp on the bottom and the measured temperature on top. I'm sure this has something to do with efficiency which is why I've started sparging for 75 minutes and raising the temperature from 149F to 152F during the mash. That's helped a little. Crushing the grain at 0.030" has provided an improvement over whatever the LHBS was crushing at but it also required that I add rice hulls to prevent a stuck mash. Mashing out vs not mashing out has provided no noticeable change in efficiency but I'm still mashing out just to keep things consistent. I'm going to step down from 13 pounds of grain to 12 pounds on the next batch and maybe even 11 on the following batch if I can manage to kick up efficiency.

I'm also doing the iodine test to make sure I've fully converted all starch to sugar. After about 45-50 minutes, the starch test shows I'm fully converted. SG measurements taken from the mash provide very similar results from 45 minutes into mash all the way to 75 minutes so I'm not sure the extra time is required. I'm fairly confident it has something to do with the sparging step that is really not provided the sugars it should be. This round (round 7) was actually the first time I was able to get sparge water on top of the grain while the grain was still under water. All previous attempts had the water draining through the grain so fast that water would immediately drop below the grain top level when lifting the basket. I'm confident that this is what's improved the efficiency on this round but I'm still far from the mid 70's I should be getting.

If I ever win the lotto, I'm going to buy one of those 3 tank systems and try this exact same recipe.

 

[Jag75]

Thanks Jag. I'm sure it's something painfully obvious that I'm missing but I'm just not able to figure it out yet. I would really like someone to take this recipe and make a batch and report results. With the brewzilla 35L, at least with mine, I'm getting about 8-10F delta between the reported temp on the bottom and the measured temperature on top. I'm sure this has something to do with efficiency which is why I've started sparging for 75 minutes and raising the temperature from 149F to 152F during the mash. That's helped a little. Crushing the grain at 0.030" has provided an improvement over whatever the LHBS was crushing at but it also required that I add rice hulls to prevent a stuck mash. Mashing out vs not mashing out has provided no noticeable change in efficiency but I'm still mashing out just to keep things consistent. I'm going to step down from 13 pounds of grain to 12 pounds on the next batch and maybe even 11 on the following batch if I can manage to kick up efficiency.

I'm also doing the iodine test to make sure I've fully converted all starch to sugar. After about 45-50 minutes, the starch test shows I'm fully converted. SG measurements taken from the mash provide very similar results from 45 minutes into mash all the way to 75 minutes so I'm not sure the extra time is required. I'm fairly confident it has something to do with the sparging step that is really not provided the sugars it should be. This round (round 7) was actually the first time I was able to get sparge water on top of the grain while the grain was still under water. All previous attempts had the water draining through the grain so fast that water would immediately drop below the grain top level when lifting the basket. I'm confident that this is what's improved the efficiency on this round but I'm still far from the mid 70's I should be getting.

If I ever win the lotto, I'm going to buy one of those 3 tank systems and try this exact same recipe.

I punched in the recipe and a 6 gallon batch came out to 6.4 abv (OG 59)and a 5 gallon batch comes out to 7.5 abv (OG 70) . This is at 80% efficiency.

Does your system have a pump ? Does it have a top screen ? You may try stirring 3 times during your mash.

 

[kappy]

One thing that keeps coming to my mind is the possibility of sparge water leaking through the gap in the segmented recirculation pipe down the middle, instead of travelling through the whole grain bed. Perhaps someone with a better knowledge of hydrodynamics would know if this would actually happen. I’ve heard reports of people removing the recirc pipe and plugging the hole in the screen, and getting better efficiency. Could that be a factor?
-James

 

[Jag75]

One thing that keeps coming to my mind is the possibility of sparge water leaking through the gap in the segmented recirculation pipe down the middle, instead of travelling through the whole grain bed. Perhaps someone with a better knowledge of hydrodynamics would know if this would actually happen. I’ve heard reports of people removing the recirc pipe and plugging the hole in the screen, and getting better efficiency. Could that be a factor?
-James

Your sparge water shouldnt be as high as the recirc pipe . If the water level goes above that then yeah it will go down the pipe and hurt your efficiency.

 

[RePete]

I haven’t been trying to calculate efficiency. But I have the Robobrew profile set in the Beersmith app. It says 72%. I usually hit OG, sometimes higher. Yesterday I brew a SNPA recipe. The target OG was 1.054 and I hit 1.058. So I think it’s doing ok. But I nearly had a stuck sparge. The draining was very slow.

One thing you are doing differently is mashing with more water initially. I start with 4 gallons. Then sparge with 4-5. I try to fill to about 6.5 gallons to boil. It’s hard to tell how much water is in the kettle, since the basket is in the way. Sometimes I over or under shoot. I don’t try to measure how much I’m adding, just watch to see how full is the kettle.

 

[kappy]

I just mean the crack underneath the telescoping part of the recirc pipe. It’s not sealed from top to bottom, so even if your sparge water isn’t entering through the top, it may be seeping through in the middle. Or that’s my theory...
-James

Your sparge water shouldnt be as high as the recirc pipe . If the water level goes above that then yeah it will go down the pipe and hurt your efficiency.