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Adding DME to top-off ice

My standard brewing method for now is all-grain, but with a partial boil (have to brew inside until i finally crack and buy a house in the burbs!). I usually can max out with a preboil volume of 5.5G, which boils down to 4.5, and then rack to a fermenter with 1.5G of ice in it to give me a net of 5.5G in the fermenter.

My efficiency suffers for this, as I dont get to run all my water through the mash/sparge, and I’ve been averaging a mash efficiency around 63% and a total BHE around 57%. I was thinking of boiling my topoff water with a lb of DME, then cooling and turning into ice as usual. This would give me another 7 points or so on the OG.

Anyone see any issues with having a little dme in the top off ice? I usually make the ice a few days before brewday, so it would only be in the freezer for a few days before I use it.

I’d probably just add the DME to the boil. One less step and no sanitation concerns.

Yeah, that would seem easier…and obvious, yet never even crossed my mind. I know you mentioned in some other post that you use a similar method somethimes. Have you found your efficiency to suffer when you have to use some of the brewing water for ice rather than as mash/sparge water? How big a difference, if any?

Agreed, add the DME to the boil.

Couldn’t you adjust your recipe to account for the additional water added at the end? What you’re doing is kind of what I’m doing as well. Due to my setup, I can only get my preboil wort to about 4.5-5gallons and I’m losing about 1/2 to 1 gallon during the boil. So I’m down to about 4 gallons post boil, but I account for this when creating my recipe. I make my boil 4 gallons and final volume 5 gallons. Hopville knows how to calculate the rest.

Something to think about.

Your efficiency will always change when you adjust the water volumes. I batch sparge, though, so it’s a predictable change. Rather than reinvent the wheel, I’d refer you to Kai Troester’s work on batch sparging:
. He also has a spreadsheet on his site that may help you out.

I’ve found that as long as my mash pH and temperature are in range, I always get >95% conversion after 60 min, and can therefore predict my overall efficiency within a couple percent. Adding ice or water post-mash doesn’t effect that, although any measurement errors are compounded by working with a smaller volume.

I kind of doubt that, actually. I’m sure it’s accounting for the dilution correctly, but I would be surprised if it was adjusting efficiency as a result. It would either have to take a large number of inputs, or make a lot of assumptions. I think it’s much more likely that you’re simply setting your efficiency correctly from the beginning.

It doesn’t adjust the eff. It adjusts the OG. Hopville assumes 75% standard eff which you can adjust. I bump it up to 80% because that’s usually where I am. So I input all the fermentables, boil volume, final volume and adjust the efficiency to 80%. The program estimates the OG. I’m usually within a point or 2 after adding my top off water and mixing well. Seems to work fine for me. Just trying to tell the OP’er that you can adjust and account for top off water.

Reading your post again, I see what you mean. And I think we’re saying the same thing. I guess my point to the OP is that you can adjust and account for top off water. Topping off with water and then checking your gravity to see you’re at 55%-60% doesn’t have to be that way. Adjust your volumes from the start, input a more standard eff (whatever that may be 70%ish?) and input your fermentables. The program should give you a correct OG estimate.

I routinely look at NB’s recipes and convert them to my own (with some tweeks of course) and have no problem matching the OG’s within reason. I don’t think efficiency is his problem. I think it’s getting the recipe and volumes input into a program properly.

I account for the realities of my system when putting in recipes, that’s not the issue. I was really just trying to determine the effect that using 1.5G of water as a topoff, rather than as either mash or sparge water- where it would be used to rinse and carry sugars to the kettle- is having on my mash efficiency.

Basically, could I expect a jump in efficiency if that 1.5G of water was used in the sparge and collected some sugars, rather than just having a pure dilutive effect. I’m tired of needing 15lb of grain to get a 1.055 beer.

Also, my experience doesnt seem to jibe with Kai’s calcs. According to him, with a 4G mash and 2.65G first runnings, I should be expecting around 66% efficiency just from the first runnings. IME, this usually comes in around 42% instead, so maybe I’m not getting full conversion, although I dont see why I wouldnt be.

Start checking your first runnings gravity to see where you’re actually losing efficiency. If it’s in conversion, crushing finer would be the first thing to try. If it’s in lautering, do you have a lot of dead space in the mash tun? The smaller the mash, the larger the effect of any dead space, proportionally.

It’s definitely on the conversion end. Dead space is negligible, and my first runnings are definitely coming up short. Last batch, with a 1.16q/lb mash ration, I got first runnings of 1.088, whereas Kai says it should be 1.100 so my conversion efficiency is 86% or so. I’ve been using a pretty fine crush, but I guess I need to start turning that $hit to flour.

Maybe your pH is on the edge, that can affect conversion. Or just do a longer mash.

Calibrate your instruments before you change anything though.

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