What you are doing is not easy and unless the website you speak of has all the information it will be very hard to get it right. Do they respond to email on the subject? There may be someone on this board who has done this but I sure don't know the answers to your questions but would be interested in what you learn in the future about this.
Look Here: http://www.mbaa.com/TechQuarterly/Ab...5/tq95ab04.htm
Warning on the website you listed: http://www.sillyyak.com.au/gfb/gfmalt.html
Health Warning - Sorghum when germinating and growing makes a hydrogen cyanide precursor in the seedling and roots. During mashing (or digestion) highly toxic prussic acid (hydrogen cyanide) is produced. The level of this toxic compound likely to be produced varies widely depending on variety. This is why its important to clean your malt well. You should remove rootlets and any acrospire growth, as this is where this chemical resides. Note that this warning can be found on page 731 in ¨Malts and Malting¨ by D.E. Briggs. I have also seen personally warnings about not eating sprouted sorghum as the sprouts are poisonous.
We have had our sorghum beer tested for cyanide levels, and less than 1mg/litre was detected. This is well below the allowable level. Our sorghum malt is machine cleaned, which removes some but not all of the root and acrospire. This and fermentation reduces the level of prussic acid to safe levels.
Fermentor 1: Bill's House Ale II, Fermentor 2: German Helles, Fermentor 3: Bill's Schworzbier (Black Bier)
Tap 1: Bill's House Ale II, Tap 2: German Hefewizen, Tap 3: Nut Brown Ale
Future Brews: Stone IPA Clone, Blonde Ale, Budvar Clone, Newcastle Clone
New toy: Blichmann 27 gallon fermentor
“If you find yourself in a hole, the first thing to do is stop digging”
“Good judgment comes from experience, and a lotta that comes from bad judgment”