another efficiency question.

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Stubbs5150

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i've been ag for little over a year and i have a couple of questions. at first i was getting 80% efficiency using a bazooka tee, crushing my own grains using a corona mill, and mashing out. i've changed to a false bottom, and do not mash out, but now my efficiency has gone down to 70%. the crush is the same, i hold the temp, amount of strike water, is the same. the only difference is the false bottom and no mash out. could it be the false bottom or lack of mash out? for the sake of argument lets say everything is the same except for the false bottom and no mash out. could it be one of those or both? and yes i've just finished a brew day and have had a few. just getting frustrated at the efficiency getting lower.
 
My guess is that you are batch sparging. If so, yes, cutting out the mash-out may have hurt your efficiency. The purpose of a mash-out in batch sparging is to get the grainbed temperature up before you sparge. Hotter wort dissolves more sugar and facilitates lautering, both of which play a big role in your brewhouse efficiency. If you don't want to do a mash out, just try sparging hotter next time and see if that improves things or not.
 
i fly sparge.....with the sparge water at 170-175 degrees for about 45 min to an hour for a 5 gallon batch. so the next time i will mash out and see if it improves. thanks.
 
There is evidence that a beta glucanase rest increases yield more than a mash out and most people seem to think the beta glucanase rest is a crazy thing to do for a few points of efficiency. I would think the same would apply to the less effective mash out.

Mash Yield/Fermentability Experiments
 
There is evidence that a beta glucanase rest increases yield more than a mash out and most people seem to think the beta glucanase rest is a crazy thing to do for a few points of efficiency. I would think the same would apply to the less effective mash out.

Mash Yield/Fermentability Experiments

This data is old and doesn't list what malt quality was used. Malts have changed in the past 14 years and so have the mashing needs.

Kai
 
Given that both rests are trying to do roughly the same thing (prevent beta glucans from harming lautering) I'm not sure the composition of the malt would change which was more valuable so much as the extent to which either was valuable.

Do you have any reason to believe that mash outs will work better than glucanase rests for improving lautering with the malts available today or just criticisms of the experiment I linked to?
 
Some of it was criticism of the experiment as it need to be seen in context of its time. The same can be said about my experiments in 10 years ;).

In addition to that, the additional rests don’t increase efficiency through increasing the lauter efficiency but through increasing the conversion efficiency. A faster lauter is not necessarily a more efficienct lauter though a more restrictive grain bed (in combination with more viscous wort) is more prone to develop channeling. But that only applies to fly sparging anyway.

The way these rests help efficiency is through increasing the conversion efficiency. I.e. they allow for more of the starch being converted during the mash. The less modified the malt is, the more starch is locked away in cell structures. These structures can be broken down by a beta-glucanase rest. Even well modified malt has still some undermodified regions of endosperm. But not much. Starch is also infested with protein and the degradation of that protein, of not done sufficiently in malting a protein rest can also help efficiency.

A mash-out raises the temp of the mash and with it the activity of the a-amylase. This can lead to more starch being converted and thus increase conversion efficiency. If you infuse hot water into a thick mash, the higher water/grist ration can also cause more starch to be converted. This is my explanation on how mash-out can be expected to raise efficiency. But keep in mind that this additional efficiency comes as unfermentable dextrines as there won’t be much b-amylase to convert them into fermentable sugars. So if the gain is significant it may also affect attenuation.

The interesting thing about the b-glucanase and the release of b-glucans into the wort is that there are 2 enzymes that are important b-glucanase and b-glucan-solubilase. The first one breaks down b-glucans and the 2nd one releases them into the wort. But unfortunately they work at the wrong temps. b-glucanase works around 40C and b-glucan-solubilase works around 65C. So by the time b-glucan-solubilase is active in mashing and releases b-glucans, there won’t be any b-glucanase to break them down b/c it already got denatured. That’s why it is the maltster’s job to make sure the malt is sufficiently modified and b-glucans have been broken down sufficiently. Only in the malting process can both enztymes work nicely in concert. I’m just bringing this up b/c b-glucans don’t cause problems when using all barley malt these days. And that b-glucan rests, while they may have a positive efficiency impact, they are not necessary and should be avoided since they also cause you to mash in the protoelytic range and the mash is also more susceptible to oxidation at this temp.

Sorry about the long winded post. But I felt to explain why doughing in that low is really not necessary for good efficiency and that the wrong conclusions (IMO) were drawn from this experiment.

Kai
 
to the OP: have you checked your thermometer for accuracy? I batch sparge with a false bottom w/no mashout and get 80+ on average. when my therm went ouit of calibration i dropped down into the 60 or lower (talk about frustrating) i finally figured it out by boiling a batch of water abd it hit 230* at boiling, normal for my area is @210*. this was causing all my mash temps to be 10-20* lower than needed including sparging with 150* water doesn't work very well.
 
i think the thermometer is ok, i'm at sea level and it boils at 212. but i will check them also. my next batch the only thing i'm changing is to add a mash out. it is a simple step and i forget why i stopped doing it. but thanks for all the input and i will put it to use.
 
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