three stage, six roller grist profiles

[bpmiller]

Coming from a four roller, two stage milling operation where a "ski slope" grist profile was the goal (max husk and course grits), i'm now working with a three stage six roller mill with the manufacturer's and TQ's published "ideal" goal of a bell curve grist profile (max fine grits I & II) with husk volumes in excess of 750ml. Are other craft breweries with such a six roller mill achieving this bell profile with good results? would you care to share gap parameters? i'm having difficulty eliminating coarse and pan flours. Many thanks!

[dick murton]

The trouble is, because of the design of the rollers, size and depth and cut edge and angle of cut of the flutes if any, the diameter of the rollers and the speed, there is no "Best" setting. There is not even a "Best" set of grist composition, because every brewhouse differs - mashing in equipment, grist to liquor, pH to a minor extent, material used, mashing profile, lauter tun design lautering profile etc. etc.

However, if it is of any help at all, one brewery I worked at used typically around 1.8 mm top gap, 1.2 mm middle gap, and 1.0 mm bottom gap on a six roll mill with sieves, malt conditioning with 1.7 % warm water, using a separate mash mixer and separate lauter tun.

Taken from an old best practice doc
Grist fractions are identified as follows where a six ASBC sieve laboratory analysis set is in use,
• Top three sieves: Husk
• Middle two sieves: Grits
• Bottom sieve and pan: Fines
• The husk fraction for conditioned malt should be > 600 ml / 100g husk
• The fines fraction for conditioned malt should be 10 - 15 %
• The husk fraction for dry milled malt should be approx. 500 ml / 100g husk
• The fines fraction for dry milled malt should be < 10 %
The grist proportions targeted will depend on extract/run-off requirements but should agree with the minimum specifications given above.

Yeah, right. But seriously, this is a typical example - note the comment about extract & run-off requirements

[dick murton]

I have also posted a response elsewhere with some different details - I thought I had replied to this already

[bpmiller]

Thank you, Dick. Yes, this is a multivariant issue as you valuably illustrated. Still, I was curious to know if other breweries were successfully using the "bell curve" grist profile.

The trouble is, because of the design of the rollers, size and depth and cut edge and angle of cut of the flutes if any, the diameter of the rollers and the speed, there is no "Best" setting. There is not even a "Best" set of grist composition, because every brewhouse differs - mashing in equipment, grist to liquor, pH to a minor extent, material used, mashing profile, lauter tun design lautering profile etc. etc.

However, if it is of any help at all, one brewery I worked at used typically around 1.8 mm top gap, 1.2 mm middle gap, and 1.0 mm bottom gap on a six roll mill with sieves, malt conditioning with 1.7 % warm water, using a separate mash mixer and separate lauter tun.

Taken from an old best practice doc
Grist fractions are identified as follows where a six ASBC sieve laboratory analysis set is in use,
• Top three sieves: Husk
• Middle two sieves: Grits
• Bottom sieve and pan: Fines
• The husk fraction for conditioned malt should be > 600 ml / 100g husk
• The fines fraction for conditioned malt should be 10 - 15 %
• The husk fraction for dry milled malt should be approx. 500 ml / 100g husk
• The fines fraction for dry milled malt should be < 10 %
The grist proportions targeted will depend on extract/run-off requirements but should agree with the minimum specifications given above.

Yeah, right. But seriously, this is a typical example - note the comment about extract & run-off requirements

[Fausto Yu-Shan]

Malt Grist Composition

At the brewery a Kunzel mill is used and to know the pilsner malt grist composition a Tyler Model RX-29 sieve shaker was used according to the ASBC method, however, it also depends who is the manufacture of the mill, as in this case the German standard is in effect.

The following results were found: