Are all sugars in grain fermentable?

[Uist Brewer]

Have just been making some granola out of the spent grains from a stovetop (4.5L) California Common kit - all helps to make the spending on kits go that little bit farther!

All went well (including with the kit, BTW) with the exception that, when thinking about how much sugar to put in, first I tasted the spent grain - and found it already quite sweet. This set a few alarm bells ringing because I'm thinking that I haven't managed to get all the sugars out of the grain and, therefore, that there is something wrong with my mashing or sparging (I'm on a BIAB set up but both recycle and sparge specifically to ensure I get all the sugars out). My OG was 1.052, which is the same as in other CC recipes in both my bibles so I must have been doing something, well, OK.

But the nagging question remains - one for chemists really, I guess (and from a non-chemist). Should the spent grains be sweet because not all the sugars in grain are fermentable? Or have I left a few behind?

 

[Drunkula]

You've left some behind, but it's to be expected. If you could swill all the sugar out of the grain you'd end up with loads of runnings and so you'd have to boil off loads and loads of water so there's a balance between grain cost, energy cost and your own time.

Also the more your sparge the more the pH can go up and the further the chances of drawing astringency out of the grain, especially if your water is more alkaline.

So basically if you're hitting figures the books have quoted you ain't doing that bad, kid.

 

[Uist Brewer]

Ah, cheers for the response. Quite often the problem with small kits in my experience is that I end up having to liquor back to get the right amount in the fermenter as a result of losing plenty in the boil! Noted wrt astringency, though. I probably should do some water testing but, this being Scotland, it's beautifully soft (if a little peaty round these parts) so should make good beer.

 

[Drunkula]

I probably should do some water testing but, this being Scotland, it's beautifully soft (if a little peaty round these parts) so should make good beer.

Soft water is the best starting point and it'll mean you'll someday be popping along to this thread and find you might be able to brew almost anything.

If you ever run into Ron Pattinson at any point then don't mention Scotland, peat and beer too close to each other. He does get a bit twitchy.

 

[Uist Brewer]

Sorry Drunkula: have only just got round to watching the clip - but noted! Notable also that the interviewer takes a bit of a step back, too

He's got a point on the word association, to be fair (and at least he didn't go down the shortbread/pale biscuity malt route!). And he's right about the history - the only breweries are in the big cities (and Alloa, where there were coal mines) which would never have used peat to smoke (because peat is only in the highlands and islands). North and west of there, it's all about the distilling. Meanwhile, Scotland has also been a place of emigration (often forced, and violent) and little history of incomers bringing their own brewing traditions and habits.

Of course, the counterpoint - and the reason why brewing is only in the major cities and that distilling dominates elsewhere - is that hops don't grow in Scotland either; they've always had to be imported. So the argument really is one based on a purist tradition vs innovation and if we stuck to the former, well, none of us would be brewing passion fruit saisons...