Diastatic Power

[Weatherby]

Checking out grain on the craftbrewer website.

Description:
EBC 18 - 27 (mash required): Dingemans Biscuit Malt is a toasted Malt that provides a warm bread or biscuit (Saltine Cracker) flavour & aroma. It will also lend a garnet-brown colour. Use 5-15% maximum. No enzymes. so must be mashed with malts having surplus diastatic power. Good in British ale.

Does this mean just mash with your base malt or is there more to it than that?

 

[Bribie G]

Depends on your base malt. I keep losing that Bairds site that talks about diastatic power but, generally, the UK base malts such as Maris Otter aren't too diastatic nowadays and can only take up to around 15% adjuncts. The Weyermann base malts will take up to 30% - I particularly asked Mr. Wey last year at the master class. Most Aussie malts such as BB or JW you can whack in the adjuncts till your ears bleed.

Edit: if I'm doing a high adjunct brew with UK malt (e.g. using more than 500g maize in a historical UK) I slip in half a kilo of Aussie Malt to act as attack dogs B)

 

[Weatherby]

Depends on your base malt. I keep losing that Bairds site that talks about diastatic power but, generally, the UK base malts such as Maris Otter aren't too diastatic nowadays and can only take up to around 15% adjuncts. The Weyermann base malts will take up to 30% - I particularly asked Mr. Wey last year at the master class. Most Aussie malts such as BB or JW you can whack in the adjuncts till your ears bleed.

Edit: if I'm doing a high adjunct brew with UK malt (e.g. using more than 500g maize in a historical UK) I slip in half a kilo of Aussie Malt to act as attack dogs B)

Thanks Bribie

 

[bconnery]

Most Aussie malts such as BB or JW you can whack in the adjuncts till your ears bleed.

Can I have that as a percentage?

 

[Bribie G]

I'll bring a 40 of my current Midnight Train Malt Liquo' to the next BABBs meeting for you to try, then your ears will bleed :icon_drunk:

 

[MHB]

Can I have that as a percentage?

The answer is more complicated than just giving a percentage, but if you chose a good base malt and had a play around with your mash temperatures you can convert 50-60% adjunct
If you read the section on braukaiser.com Understanding Efficiency Diastatic Power you should be able to work out an answer, naturally its all in Lintner and Lovibond, all the malt specs issued in Australia are in Windisch-Kolbach units (WK) and EBC, Wikipedia has a conversion for WK, and probably one for converting between Lovibond and EBCif you follow the linke in the next paragraph.
MHB

 

[Ironsides]

Sorry to hijack this thread, but i dont think its worth starting another.

Does anyone have any experience with how much diastatic power is lost with exposure to oxygen? The problem is that i have been buying grain precrushed and I have no idea how long the grain has been sitting around. I suspect that this is contributing to unpredictable efficiency.

Does anyone know about this?

(i searched for any similar threads ad found nothing)

 

[Weatherby]

Sorry to hijack this thread, but i dont think its worth starting another.

Does anyone have any experience with how much diastatic power is lost with exposure to oxygen? The problem is that i have been buying grain precrushed and I have no idea how long the grain has been sitting around. I suspect that this is contributing to unpredictable efficiency.

Does anyone know about this?

(i searched for any similar threads ad found nothing)

post away mate, it is an interesting question

 

[Thirsty Boy]

I dont know a lot about malt losing its DP over time, but i know it does happen that malt goes "slack" - i dont recall reading very much about anyone quantifying just how slack it might go.

BUT - i suspect a fair chunk of what you are experiencing with your malt might well just be moisture absorption. malt is really quite dry when its shipped from the maltster and crushing it and not storing it in a nice well designed malt silo or a sealed bag, allows it to pick up atmospheric moisture. So if you malt at 4% has managed to pick up a bit of moisture and now its at 8% - well, when you are trying to work out your efficiency, your calculations will assume what you are adding is all "malt" but really you are adding 96% malt and 4% water... That'll play merry hell with your calculations.

In general, if its stored nicely sealed away from air and moisture, crushed malt has a pretty good shelf life, not as good as uncrushed malt, but I would have no hesitation in keeping a sealed bag of crushed malt for multiple months and expecting it to be perfectly good.