Questions about methodology and efficiency

[Labradork]

Hello All,

I am new to all-grain brewing, and seem to be having problems with my efficiency. Even though I am controlling my temperatures well during the mash (using a Rubbermaid, 10 gallon water cooler), my last two batches were too high on the OG the first time and too low the last. The first time this happened I simply diluted the batch slightly and that brought me pretty close to my target. That batch is kicking back in secondary and is looking fine.

This last time, mindful of the difficulty of the previous batch, I took the precaution of checking the gravity before the boil, so I could correct it through dilution or boil-off. I used a pre-boil gravity/volume calculator to see what my gravity should be to make a 5.5 gallon batch from the 6.7 gallons I was starting with after sparging. My pre-boil gravity was much lower than it should have been, so I continued to recirculate the sparge water for quite a while until the system clogged up. The gravity was still too low. The only way I could see to raise the pre-boil gravity was to reduce the volume by boiling it down to about 4.5 gallons, then start with the hop additions and a 60 minute boil. The result is about 3.75 gallons of wort which came out within a couple of points of my target O.G.

So, finally, my question: Since the recipe :

https://www.homebrewtalk.com/f66/black-death-irish-death-clone-277213/

is for a 5.5 gallon batch, and this batch is actually only about 3.75 gallons, should I have cut the hop additions back by about a third or so? Is this brew going to come out extra hoppy? Is there anything I can/should do to correct this issue?

Follow-up questions:- Did I do the right thing by reducing the wort volume as much as I did, or should I have kept the volume the same and added extract to bring the OG up?. I'm sorta reluctant to add extracts as I'm trying to be a better all-grain brewer and using extracts would seem to be like putting the training wheels back on.

- I'm getting all my grain from my LHBS and he mills it all for me, so I'm pretty sure that part of the equation is pretty consistent. Assuming my mash temps and times are as they should be in the recipe, why am I having such difficulty with efficiency? How do I get more consistent?

Thank you all very much for your help.

Labradork

 

[LovesIPA]

It should come out more bitter and hoppier than intended, but that doesn't mean it won't be drinkable or even quite good.

In the past when I've been short on gravity points, I've added extract to make up for it, but since I bought my own mill I haven't had any issues at all. Just because the same person milled your grains on the same equipment for both batches doesn't mean somebody else didn't come along and mess with the mill gap setting in between. The only way to 100% control your crush is to buy your own mill. Since crush is the single biggest factor that determines efficiency, it's also most likely the reason that you are not seeing consistent results. Of course, I'm basing that on an assumption that you didn't change your process between the two batches other than taking the pre-boil gravity.

Mash temp or length isn't going to change efficiency that much. Depending on how accurate your thermometer is, you might not be mashing at a consistent temperature but that won't affect efficiency very much, if at all.

 

[blizz81]

Temps shouldn't really have an impact on efficiency unless you're getting way too high or way too low. (using a quality thermometer / know it is more or less in calibration?)


With batch sparging, there's kind of an inherent struggle with efficiency vs. preboil volume as you get into bigger and bigger beers namely because you start to run out of sparge water volume. I don't think you're scraping against that here too much yet, as you're still sparging with 3.7gal, which is probably a little more than your first runnings were. But something to keep in mind regarding why efficiency might be different between batches in general.


As to if you "did the right thing" by reducing wort volume, this would be brewer's preference I'd think. Some people would take more beer at a lower OG and run with it. Some might prefer to boil it down. Some would do the first and yeah, add extract and / or sugar to boost.


I'd say just read efficiency tips (such as in the AG sticky) - some personal suggestions would be to make sure you're stirring really well when you dough in / dough in slowly, try a longer mash time, buy your own mill so you know what your crush is and that it remains the same. Crush is a big player re: efficiency.

 

[blizz81]

Chuckling as it sounds like I just paraphrased what LovesIPA said....but we were only 1 minute posting time apart, I swear!

 

[LovesIPA]

Hey at least we're on the same page!

 

[Labradork]

Thank you very much. I appreciate the info and advice. I'll look into getting my own mill, as well as making sure my thermometer is accurate. I'm not sure what I will do with this beer. Irish Death is a personal favorite of a buddy and I, so I was reluctant to change the recipe by adding extract. On the other hand, having more hops/gallon has already changed it, so at this point it's more about making what I have closer to the original. I might try doing a 2 gallon version of this recipe with extracts (without the hops) and adding it in to the batch that's already going.

Wish me luck!

Labradork