cyanide in sorghum shoots/acrospires

i'm in the process of malting my own white sorghum and buckwheat and have been doing research on the cyanide levels in the shoots of germinated sorghum.
do you have to remove the shoots? what i mean is, if you just use the grains in the mash without shoot removal, will cyanide leak into the wort? or do you have to eat the acrospire in order to ingest the cyanide or consume a lethal dose? thanks for the help, happy brewing.

I've never used sorghum, but the acrospire is removed from barley, I would assume you'd do the same thing with sorghum and buckwheat.

1. The cyanide is in the roots, so you'll want to remove the shoots

2. The shoots taste bad, so you'll want to remove them anyway.

So I guess the question is how do you remove the roots effectively?

I don't really have the time or patience to pick off each one with a set of tweezers and a magnifying glass.

Malsters use a screened/perforated drum. Like a sieve. the shoots fall through and the grain stays in teh drum.

Short of that, malting your own is tedious.

aggieotis said:

So I guess the question is how do you remove the roots effectively?

I don't really have the time or patience to pick off each one with a set of tweezers and a magnifying glass.

Click to expand...

I found that drying them in the oven makes the roots brittle. If you then take the malted, dried sorghum and put it in a pillowcase that is sealed and throw it into the dryer to tumble, 99% of the roots will be knocked off. After that I just poured everything onto a screen and shook it, roots fell through and the grain stayed in...

Just wanted to confirm what a previous reply said. Malted sorghum does contain cyanide (and cyanide-like) compounds, so you definitely want to remove the roots and shoots. It will come through in the beer, and at times has been a problem in Africa were sorghum is heavily used in traditional sour opaque beer brewing. Children, because of their lighter body weight, are especially susceptible to the negative side effects, but you don't want to play around with that kind of thing regardless...

Cheers, Pete

Been concerned about this myself. All GF batches to date have been with sorghum extract and lesser amounts of millet, amaranth, quinoa, buckwheat, or oats (though not all at once :cross as steeped adjuncts. Now I have a 5g bucket of sorghum grain waiting to go, but haven't felt comfortable pulling the trigger on AG sorghum. However, it appears that wet heat (>100*C, ie during boil) and/or significant dry heat (>180*C for 15min, ie roasting malt @ 360-400*F) does the trick. Certainly coupled with mechanical removal of acrospires and rootlets, these methods should suffice for double secret probation sorghum safety.

Check out this post on another GF beer thread: http://www.gotmead.com/forum/showpost.php?p=128652&postcount=29. It contains three citations itself, the last one being a report from the WHO that cites the above heat data.

---Bob

Sorghum, like cassava, contains cyanide precursors, the levels of which are variety dependent. As indicated above, the cyanide precursor is thermally labile, so heat helps to degrade the precursor. Although HCN is volatile, bear in mind that there will be an appreciable proportion of cyanide anion in solution, unless your mash is really acidic, which reduces its volatility.