Frozen grain=amazing mash efficiency?

Physics, chemistry and biology of brewing. The causes and the effects.

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etbandit
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Re: Formula for mash efficiency.

Post by etbandit »

billvelek wrote:Ten pounds of Briess 2-Row in 5 gallons final volume water, at 100% efficiency, yields an O.G. of 1.071, or basically 7 points per pound. So, for example, if you use 8 pounds of Briess and get an O.G. of 1.042, then I would calculate it like this: 10/8 x 42/71= 73.9%
Bill Velek
Should I be using the OG reading of the kettle wort before the boil, or the OG of the wort at the end of the boil, when calculating my efficiency?
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Re: Formula for mash efficiency.

Post by billvelek »

etbandit wrote:
billvelek wrote:Ten pounds of Briess 2-Row in 5 gallons final volume water, at 100% efficiency, yields an O.G. of 1.071, or basically 7 points per pound. So, for example, if you use 8 pounds of Briess and get an O.G. of 1.042, then I would calculate it like this: 10/8 x 42/71= 73.9%
Bill Velek
Should I be using the OG reading of the kettle wort before the boil, or the OG of the wort at the end of the boil, when calculating my efficiency?
I might be wrong, but I don't think it makes any difference as long as you take into consideration the volume of water when you take your hydrometer reading. In other words, 16 gallons of 21 point wort has the same amount of sugar as 8 gallons of 42 point wort, but I don't really know how that plugs into the math that I did earlier except that I would suggest that you do a ratio of your volume of water to the 5 gallons that I used from BTP. As I said, that really isn't a formula, but just a way to compare with what BTP calculations come up with.

What you really need is a formula so that you don't need values form BTP; I'm sure there is one out there somewhere, but I have no idea where to look. Good luck.

Cheers.

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Mesa Maltworks
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Re: Formula for mash efficiency.

Post by Mesa Maltworks »

..."What you really need is a formula so that you don't need values form BTP; I'm sure there is one out there somewhere, but I have no idea where to look."


I can supply the correct efficiency equations if you can specifically state what you are looking to determine.

One point that is important to mention: if you read a malt analysis sheet, they list the congress mash (a lab proceedure where they turn all of the malt into a fine powder and mash it for 15 minutes) result to give the figure for the FG/DB (fine grind, dry basis). Even when mashing in this way the MAXIMUM efficiency you can get is 86%. The results in all commercial breweries are lower than that (my average brewhouse efficiency is 82%) and for homebrewing the efficiency tends to be even lower (average is 70%). I continuously see homebrewers who state that they have 90-100% efficiency. This is impossible and I can only guess they are getting actual efficiency confused with getting 90 to 100% of what they calculated when formulating a recipe. The most important measurement point is where you end up after you knock out the wort to fermenting temperature. When you measure the SG and the actual volume prior to the onset of fermentation you can use this to determine your whole brewing efficiency, not just the mash efficiency.
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Re: Frozen grain=amazing mash efficiency?

Post by pcharles »

Fraoch wrote:OK, i normally get a very good mash efficiency anyway, around 85 - 90%, but for the last 2 brews ive used grain that has been stored in the freezer, i crack it whilst still semi frozen and mash the next day,the results are phenominal as my efficiency has risen by 5% or more, hitting 99 and 97% respectively.Anyone else do this???? or like to try it and offer a second opinion???I find it all hard to believe myself!!
I support the idea that freezing process could be rupturing cell walls, which can make it easier for the enzymes to access the goodies inside.
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Re: Formula for mash efficiency.

Post by pcharles »

Mesa Maltworks wrote: Even when mashing in this way the MAXIMUM efficiency you can get is 86%. I continuously see homebrewers who state that they have 90-100% efficiency. This is impossible and I can only guess they are getting actual efficiency confused with getting 90 to 100% of what they calculated when formulating a recipe.
So, how do you explain a case where the software predicts that a 75% efficiency should give a final gravity of 1.068 in 6 gallons, but the final gravity is actually 1.080. I measured the grains very carefully, and crushed them with a modified corona mill. They were mashed at 154
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Loss of grain aroma/flavour from pre-crushed grain?

Post by etbandit »

Has anyone experienced the loss of aroma, flavour, and/or freshness in their beer from using grains they pre-crushed, say 1 day, 1week, 2 weeks to 1 month etc. prior to their actual brew day.

I order grains that the brew store crushes for me the day before my brew day. Im wondering if it would be better (in terms of retaining maximum grain aroma/flavour/freshness etc.) to purchase my own grain mill and crush my grains just before mashing in?

Any suggestions?
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