Brewzilla very low efficiency

[rhett]

Hello,

I recently bought a Brewzilla 65 L and I have been getting terrible efficiencies. The best I have had was around 62%. Yesterday I got just 42%. Previously using home-make kit I was getting in the high 70s. I am fairly confident the water chemistry and pH are fine. I measured the pH using a paper strip and got 5.4.

Two things I have changed are that I am now milling my own grains (but the crush looks fine) and that I am using the Brewzilla. I am wondering if the sparge step is the problem. The wort drains out very quickly from the grain bed as I raise the mash tun and then the sparge still takes only about 20-30 mins (17 L yesterday). I was thinking of blocking some of the holes in the bottom of the tun to slow down the rate it drains. On the mill, I do not have any tool to measure the width (getting supplies is a challenge here), but it seems ok. Currently I have it on the max which breaks all the grains but does not produce too much powder.

Rhett

 

[Minbari]

Efficiency is all about crush and water. Sounds like your ph is ok, so I would look at your crush. Considering your sparge takes no time, that would also point towards too large a crush.

Also look at mash time. Are you testing your mash to make sure it is done or just timing it?

Edit: also also, what temp are you mashing at?

 

[soccerdad]

I don't know enough about Brewzilla to offer advice, but from what I have seen and read it is similar to BIAB. In that vein, BIAB efficiency can often be improved with 2 simple things: 1) crush grain a little finer, and 2) mash a little longer.
Some folks say to set a mill gap using an old credit card. Use that as your measure. Or try it anyway.
Don't think that 60 minutes is a magic mash time. 90 or even 120 minutes is not out of the question.

 

[Minbari]

I don't know enough about Brewzilla to offer advice, but from what I have seen and read it is similar to BIAB. In that vein, BIAB efficiency can often be improved with 2 simple things: 1) crush grain a little finer, and 2) mash a little longer.
Some folks say to set a mill gap using an old credit card. Use that as your measure. Or try it anyway.
Don't think that 60 minutes is a magic mash time. 90 or even 120 minutes is not out of the question.

This exactly! Diastatic power of the grain, ph and temp will determine the time it takes. It's done when it's done

 

[HighVoltageMan!]

Yesterday I got just 42%.

That's crazy low. It seems to me you're leaving a lot of sugar behind or you have a severe conversion problem. Are you circulating the entire time? Did you perform an iodine test? Fast sparging can take some efficiencies away, but no that much. Mashing longer can improve conversions, but it mostly effects fermentablity and final gravity. Efficiencies are less affected by mash length.

Recheck your system, make sure the recirculation is not being short cut from a channel or hole in the grain bed. Sparge slower, it can take an hour or more to do a decent lauter/sparge.

Good luck.

 

[GFHomebrew]

Alright I'm new to the grain mill but not new to reading forums and garnering little gems of brewing how to information and trying it out for myself to back up the results.

Grab your key card or lesser important card.
Insert this into your rollers untill you can run it back and forth through without it pinching too much.
I BIAB I've found this crush has increased my mash efficiency and that's after 100+batches milling with thermomix.

I'm thinking your maybe removing the husk but not crushing the grain/kernel and when your doing your hour mash or so your amelayse enzymes just can't access the starches.

If my efficiency is down first thing I'll always address is the crush it is a BIG player when it comes to efficiency.

Then check the actual grian bed temp with thermometer them all in ones as well as mine can be out a few degrees from set point.
So say you've mashed in at 66c and it's out by 4 or more degrees you may actually be mashing at the bottom end of the saccrification range like 60c.
You'll convert but in theory you wanna add more time as the beta take their merry time in the mash.
Photo of crush too please .
Good luck on the next batch teething problems is all we all get them on new equipment.

 

[Donoroto]

How are you measuring efficiency? At what temperature do you mash? What grains are being used? The previous posts covered likely causes, but perhaps it is something else.

I regularly get 78% with my Brewzilla 35. A 2 gallon sparge takes me 8-12 minutes.

 

[Coaltaine]

The above looks terribly helpful. Am having the same efficiency issue after my first two all-grain brews in the zilla. Thanks for posting and the replies. My current plan is to set the mash temp just a bit higher so any variation doesn’t dip down too low, and I will add time to the mash. Eventually, I will keep either time or temp constant to seek a solution based on one variable.