[Kaiser]

If the trapped sugars (in solution) inside the grains were able to be mechanically extracted, one would acheive better efficiency. That's assuming there is a significant amount of available sugars to extract which I believe to be true.

I don't think that there are actually a lot of sugars trapped inside the grain. When I mean indide the grain I mean inside the grits. The mash gives enough time for those sugars to leach into the mash liquid. A fact that can be verified by testing the mash gravity. Once that is done it is all about whashing the sugar rich wort off the outside of the pieces that are the spent grain. There might be some diffusion happening from inside the grits into the sparge water but I deem that effect to be minimal. If it was true that a significant amount of sugar has to be extracted from the grits during the spare the rest time during batch sparges would matter.

Agitation during mash helps by providing some mechanical force that helps distibute enzymes, product and substrate. It helps during lautering b/c it breaks up channels that may have formed.

Kai

[bluesman]

If the trapped sugars (in solution) inside the grains were able to be mechanically extracted, one would acheive better efficiency. That's assuming there is a significant amount of available sugars to extract which I believe to be true.

Agitation during mash helps by providing some mechanical force that helps distibute enzymes, product and substrate. It helps during lautering b/c it breaks up channels that may have formed.

Kai

For instance...stirring and/or some other mechanical means during the mash would facilitate the transport of sugar into solution. This action would make for a more homogenous wort which would enable or encourage more gelatinization thereby enhancing lautering efficieny.

[Kaiser]

For instance...stirring and/or some other mechanical means during the mash would facilitate the transport of sugar into solution. This action would make for a more homogenous wort which would enable or encourage more gelatinization thereby enhancing lautering efficieny.

Getting more starch gelatenized should affect conversion efficiency but not so much lauter efficiency. The latter assumes that conversion has stopped and that there is no additional creation of soluble sugars during the lauter. An assumption that may not always be true and might be the explanation why some brewers see an impact of the sparge water temp on their efficiency.

Kai

[bspisak]

Ok, so can I revise my conclusions as follows?

1) The lauter efficiency of a perfect fly sparge will always be equal to or greater than a perfect batch sparge for a perfectly designed lauter tun (such as Figure A.)

2) The lauter efficiency of a perfect fly sparge will be negatively impacted by a sub-optimal lauter tun design (such as Figure D) such that batch sparging may provide higher lauter efficiency.

On the subject of stirring, would stirring during lautering nulify the negative effects of a sub-optimal lauter tun design when fly sparging such that lauter efficiency of fly sparging again exceeds that of batch sparging?

Brian

[MDixon]

Some breweries actually use a plate and frame filter to "squeeze" out the mash to get every last drop of liquid and the highest possible yield.

Here is said beast at Rodenbach

[stout_fan]

Some breweries actually use a plate and frame filter to "squeeze" out the mash ...

Whenever I've tried that I get a lot of tannins in my beer. I wonder what they are doing different.

[stout_fan]

... Did you know that the swan-neck design seen on the faucets feeding old lauter grants ...
Kai

Thanks Kai, but I'm not visualizing this. Any links to photos?

[bluesman]

Some breweries actually use a plate and frame filter to "squeeze" out the mash to get every last drop of liquid and the highest possible yield.

Here is said beast at Rodenbach

This is the what I was talking about in an earlier post regarding "mechanical extraction". If one was to mechanically extract the wort from the grain bed after the sparge, there would be a significant boost in efficiency. At least that's the theory. I haven't proved that as of yet.

[Kaiser]

Here is one from the old Maisel's brewery in Bayreuth Germany:



But I think I misspoke. The highest point of the swan-neck is in line with either the lauter tun floor or false bottom. But the intenion of reducing suction on the grain bed remains.

Kai

[bspisak]

Some breweries actually use a plate and frame filter to "squeeze" out the mash ...

Whenever I've tried that I get a lot of tannins in my beer. I wonder what they are doing different.

Perhaps it's a pH issue?

[Kaiser]

The mash filter problems I read about were not tannins but slightly more cloudy worts with higher lipid content. The latter is the result of pulverizing the grain and with it the embryo during milling. Tannins could be a pH issue.

Stout_fan, when you squeezed the grain and got tannins, was that when you steeped them in a bag?

The closest home brewers can come to mash filters is Brew-In-A-Bag (BIAB). There you can squeeze the bag to up efficiency.

Kai

[denny]

Some breweries actually use a plate and frame filter to "squeeze" out the mash ...

Whenever I've tried that I get a lot of tannins in my beer. I wonder what they are doing different.

Perhaps it's a pH issue?

That was my thought, also.

[stout_fan]

Stout_fan, when you squeezed the grain and got tannins, was that when you steeped them in a bag?

IIRC it was a mini-mash. You are correct it was in a grain bag. I believe the act of squeezing them upset the grain bed and caused all the little bits to spill out. Now if you can maintain the bed somehow, I should be possible.
Sure would like to see the internals on that press. A lot of sugars are lost and recovery of those in a commercial operation would be of considerable financial impact.