Why am I getting such good efficiency?

[Netflyer]

I just can't get a handle on my efficiency. I use a 10 gallon igloo cooler with a round false bottom. I'm getting 75% with batches around 1.060 and about 85-89% with smaller batches. Everytime I try to follow a recipe I'm afraid to dial my eff. up that high but then I overshoot by as much as 10 gravity points. I made Orphy's Mild Mannered Ale this past weekend and I should have been at 1.037, his recipe was dialed in at 70% eff. and I scaled it for 75% and I still overshot and hit 1.043 ... It's driving me crazy and I think I just have to believe I will get 85% and scale for that. What I can't understand is what I'm doing right. I know that seems like a weird question but why do these recipes use 70% as their target eff. Is that much more common than 85ish? I'm not doing anything special here, just grind the grist, pour in the hot water, mash in, make sure I've hit my temp., let it sit for the prescribed amount of time and then I empty the mash tun and do a batch sparge with two allotments of sparge water... so typically to put 8 gallons in my kettle I initial mash with 2.5-3.5 gal and then add the rest in two doses. So I'm batch sparging and getting in the upper 80's. Why do other people get in the lower 70's or even in the 60's with small beers? I can understand big beers and having all the grain exposed during mashing problems causing the eff. to be lower, I've experienced this with my 1.070ish IPA's but I'm still in the mid 70's.

Thanks for any thoughts here...

 

[kryolla]

take a pre-boil gravity reading and pre-boil volume and adjust from there to hit your OG as far as you not being consistent in your eff while your process is the same IDK . Can you taste the difference between 1.037 and 1.043?

 

[Homercidal]

I'd make sure you measured the volumes very carefully.

I started out getting over 75% and got up to above 80% after my first AG. I used beersmith and calculated for 75% and always overshot. Now I aim for 82% and am much closer. Lucky I guess.

If you have a good crush and a good manifold system, there is no reason not to get an good efficiency.

 

[DKershner]

It sounds to me like you need to mash longer on your bigger beers. You are probably mashing thinner with the small beers and converting better. That is about all I could come up with if the rest of the process is exactly the same. Trying mashing longer and see if you hit the mid 80s all around.

Oh, and as for why you are higher than others, usually the answer comes down to crush. I aim for around 80% with my crush because I know any higher than that can cause some stuck sparging or transferring with my system at the speed I like to transfer. Most LHBS's or big box stores aim for 65-75% which is probably why you see that quite frequently.

 

[Netflyer]

Yeah, I think maybe the crush is really pushing the eff. up now that I think about it. I had two stuck sparges in this last batch. I had to close the valve, re-stir, re-vorlauf, and I was ok... I've heard rice helps with that but perhaps I need to open the barley crusher a bit?


I probably can't taste the difference between 1.037 and 1.043 however... If I am brewing a mild and I want it to be lower in ABV because I want to have it at a party and don't want the non-homebrewians to get too toasted I really want to hit that lower number. I need to make a 1.036-1.038 brew.

As for the preboil gravity, I always take a preboil and I know I'm screwed at that time because I've overshot. How can I adjust if I have the max amount of gallons in my kettle already, 8-8.5? I need to boil for at least an hour, which I do and then I'm left with a gravity that is higher than I want. So, what to do? Water it down? Been there and I would rather not do that... I just drink the batch and make another one for the party

I'm just going to dial in 83ish in beersmith and give it a go... I feel like it is easier to go up so if I get to 1.035 after an hour I can always just keep boiling and just have less in the fermenter... Don't ya think that is better than adding fresh water? Or would you add water to the boil and boil longer?

 

[Homercidal]

If you have room in the kettle, feel free to add water in the kettle. Or add sanitized water to the fermenter. Either way. Or not worry about it, like I do. A couple of points either way is not going to "crush" me (pun intended).

If you are getting stuck sparges, and want them to stop, think about either changing your system, or adjusting the gap a hair and lose a point of two of efficiency (maybe). The gap is easier, and you are still likely to get a very good efficiency.

Then there is the option of leaving it and adding some rice hulls, which is pretty cheap and easy too.

 

[Brewenstein]

As for the preboil gravity, I always take a preboil and I know I'm screwed at that time because I've overshot. How can I adjust if I have the max amount of gallons in my kettle already, 8-8.5? I need to boil for at least an hour, which I do and then I'm left with a gravity that is higher than I want. So, what to do? Water it down? Been there and I would rather not do that... I just drink the batch and make another one for the party

I had a big increase in efficiency when I started ordering from BMW and this continued when I got a grain crusher. (From 65-70% to 82-87%). One way I compensated for this was to brew a slightly larger batch - instead of the 5.5 gallons the recipe called for, I bumped it up to 6 gallons. More beer at the right OG. Or you can decrease the amount of base grain by a pound or so. I like the more beer route myself :rockin:.