Why doesn't Biscuit Malt have diastatic power/how is it made?

[bigbeergeek]

I can't find any technical info on how biscuit malt is produced. It doesn't seem to be a crystal malt but a "roasted malt." It's not deeply roasted, but it's always referred to as a "malted" grain. Why no diastatic power then? Any insights on what biscuit malt actually is/how it's produced?

 

[GilaMinumBeer]

Everything I've seen suggests it does have some DP (~6) but not much. I suppose that roasting it at 350*F denatures the enzymes.

 

[chickypad]

Came across this article in the past, gives a nice summary. You'll see victory and biscuit mentioned at the end. They take base malt and put it in the roaster (just lower time and temp that the dark roasted malts), so sounds like it's this phase that denatures the enzymes.

 

[Aristotelian]

My understanding is that biscuit malt is plain base malt that is simply toasted to about 20L. There are some brewing sites that tell you how to easily toast your own. It is different from 20L Crystal/Caramel malt in that it is does not go through the crystal process that makes the sugars unfermentable (leading to a sweeter beer). However, I have no idea why it does not have diastatic power, but I guess the toasting eliminates the enzymes?

 

[biertourist]

The thread already pretty much covers it. But they take base malt and then roast it until it gets to 20L; the longer you roast malt and the higher the temperature you do it at, the more you degrade the enzymes until you don't have any enzymes any more.

You see the same thing with Munich malts, but, and I'm doing this from memory so I could be wrong, with munich Malts you're still starting with "Green" malt and you jump ramp up the temperature at the end of the drying cycle. If you look at the DP rating vs. Lovibond color ratings for Briess's Munich malts, you'll see at 10L the Munich malt still has a DP of 30 (minimum to self-convert with a 100% grist in 1 hour) and by the time you get to 20L Munich, you're down to a DP of 15. -The Biscuit / Aromatic / Amber / Brown /Black malts are dry-roasted so I'd imagine at the same temps and time they denature even faster, too.


Adam