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.
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.
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 resultsI 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.
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.
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.
I did try to mash in with 4 gallons of water and 13 pounds of grain but that didn't go well. I ended up adding another 1.25 gallons (5.25 total) in order to get all the grain wet. It was also a huge PITA to get the water to circulate so I went back to 6.09 gallons in the mash tun.
That makes sense that halfway down that mash pipe, we're loosing liquid that didn't have a chance to push to the bottom. I'd be curious to see just how much liquid works it's way out that way.
I think efficiency can really be dropped if/when you constantly stir vs. allowing the grain bed to set. I noticed on this latest round that the grain bed dropped a good 3" from start to finish.
I also noticed in the instructions that we're suppose to push the pipe as far down as possible so the metal fitting at the top sits flush with the top metal cover. I've never actually tried that as I leave the malt pipe in the locked position (where the indent is on the lower pipe) so to kappy's point, I wonder if that opening is causing liquid to flow through the pipe vs. the grain.
What is the heaviest grain bill you have done? I've done 16lbs, and thought that might be about the limit. Haven't tried extending the center pipe with tubing though. I have plans to brew a Russian Imperial Stout, and the grain bill is around 20lbs total. I may need to scale down the recipe for 4 gallons instead of 5.I’m tracking with that although not sure I reach 80% too often, maybe range 72-75% - most of my beers are 13-16 lb grain though. I have no issues with leaks. I always use a hop spider...
I've done up to 16.5 lbs but am most comfortable at 16. I tried a 4 gallon yield once, now I sub DME for some of the base malt on my highest gravity recipes. I just brewed a Barleywine with 16 lb grain and 2 lb DME plus I've done a hop slam clone with similar ratio. Besides extending the center tube I also duct tape the mash handle holes. I hate to let grain float into the kettle! I'm still debating the imperial stout, will probably try one after I do a lower gravity oatmeal stout.What is the heaviest grain bill you have done? I've done 16lbs, and thought that might be about the limit. Haven't tried extending the center pipe with tubing though. I have plans to brew a Russian Imperial Stout, and the grain bill is around 20lbs total. I may need to scale down the recipe for 4 gallons instead of 5.
Yeah, hence the 65L version (came long after I bought my unit). I'm pleased with the DME on the hop slam clone, will do it again for sure. My barleywine is still aging...Yeah. I may go the DME route. Or, I still have my old cooler mash tun. I’ve just been using it to hold sparge water. But I could mash in that and then drain into the Robobrew to boil.
At any rate, this is one of the limitations of the unit. It’s difficult to do big beers. At least 5 gallon batches.
Also dial in your pre boil volume. For me, Beersmith calculates my pre-boil and I’m learning that I need to hit that number spot on: too little and I don’t fill my keg, too much and my pre boil SG drops. That’s what I use a sight tube to set that level as you can’t see your volume with the RB setup.
My mill has markings at .050 and .025. I tried one batch set with a credit card, and had a stuck large. I have set it half way between those recently, but think I will back it off some more. It will drain, but is dreadfully slow. Personally, I think people are too concerned about efficiency. I would rather just add a little more grain, and enjoy the process. We aren’t doing this to make a living. This is a hobby after all...Hi guys, I did my first brew last week and I almost had a stuck sparge in my 35L. It took a long time for it to drain. I wonder if I milled my grain too fine. I set the mill a hair under .5. I used a credit card to set the gap so the card was held, but the roller would still move with it. Think it was still too fine of a mill, should I make it a little courser?
Thanks
I have the evil twin mill and it goes .05 to .025. I tried to get the cereal killer, but getting what you want seems to be a thing of the past. I actually wanted to get the anvil foundry, but once again, getting what you want appears to be a relic of a simpler time.My mill has markings at .050 and .025. I tried one batch set with a credit card, and had a stuck large. I have set it half way between those recently, but think I will back it off some more. It will drain, but is dreadfully slow. Personally, I think people are too concerned about efficiency. I would rather just add a little more grain, and enjoy the process. We aren’t doing this to make a living. This is a hobby after all...
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