Ss Brewing Technologies Giveaway!

Home Brew Forums > Home Brewing Beer > All Grain & Partial Mash Brewing > What determines diastatic power?
Reply
 
LinkBack Thread Tools
Old 09-07-2007, 02:09 PM   #1
jeff
Feedback Score: 0 reviews
 
jeff's Avatar
Recipes 
 
Join Date: May 2005
Location: Lexington, KY
Posts: 56
Liked 1 Times on 1 Posts

Default What determines diastatic power?

Hi all,

What determines the diastatic power of a base malt? Is it inherent to the type of malt, or does the malting process and level of modification affect it at all? I understand that you have to malt in order to activate the enzymes, but is the number you're going to get pre-determined by the malt variety, or can the amount of enzymes be altered by the level of modification? It seems that American 6-row is high in DP, and it is typically under-modified to increase yields. Is there a correlation or is it simply coincidental?

Thanks!

__________________
jeff is offline
 
Reply With Quote Quick reply to this message
Old 09-07-2007, 02:49 PM   #2
thebikingengineer
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2007
Location: Columbus, Ohio
Posts: 210
Liked 1 Times on 1 Posts

Default

It all depends upon the maltster. I don't know much about malting, but I think there's a point in germination where you reach the maximum and that's generally where they'll kiln to stop it. You might wait for a more definitive answer though.

__________________
thebikingengineer is offline
 
Reply With Quote Quick reply to this message
Old 09-07-2007, 03:01 PM   #3
Got Trub?
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2007
Location: Washington State
Posts: 1,538
Liked 7 Times on 5 Posts

Default

D) All of the above.

The strain of barley, the growing conditions and the malting process all influence the DP. It will also change with age and storage conditions.

__________________
Got Trub? is offline
 
Reply With Quote Quick reply to this message
Old 09-07-2007, 03:08 PM   #4
Glibbidy
Feedback Score: 0 reviews
 
Glibbidy's Avatar
Recipes 
 
Join Date: Oct 2005
Location: Sunny Southern Vermont
Posts: 2,399
Liked 12 Times on 11 Posts
Likes Given: 2

Default

Don't forget color. DP decreases as color increases.

__________________
Glibbidy is offline
 
Reply With Quote Quick reply to this message
Old 09-07-2007, 10:14 PM   #5
Dr Malt
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2005
Location: Pacific Northwest
Posts: 287
Liked 12 Times on 12 Posts

Default

Hi Jeff.

DP or Diastatic Power of malt is a measure of the starch digesting ability of a group of enzymes found in malted grains. Growing season has some influence, but not dramatic. The potential level of DP is set by the particular barley variety. However, in developing malting varieties, plant breeders select malting barley for the it brewing qualities of which DP is one. Thus, barley malting varieties today all have the potential to develop DP in the 130 - 160 range. When the maltster is making a base malt from a given variety of barley, he develops these enzymes during the germination process. However, when he dries the malt in the kiln, he sacrifices some of the enzymatic activity to get the proper color and flavor in the finished product. High heat at high moisture results in enzyme denaturation. The maltster dries the malt carefully at lower temperatures (90 - 100F) to get the moisture down to 12% or so. He then increases the temperature to about 180F to develop color and flavor. Most of the enzymatic activity is saved by doing this. Obviously, there is some variation in DP batch to batch so each lot is analyzed for its DP level as well as several other parameters.

Now for barley malts of higher colors, like pale ale malt, Vienna malt, and others, the DP levels go down with increasing color. Roasted malts like caramel malts, chocolate malt, etc have no DP. Malted wheat has a DP like barley base malts.

6 row barley once had a significantly higher DP level than 2 row. However, today the difference between these is much smaller. For example, a 6 row barley malt runs 150 - 160 DP and 2 row 130 - 150. For us all-malt home and craft brewers, this is excess DP for brewing. For brewers who make beers containing starch adjuncts ( AB, Coors, etc), they need the higher DP to breakdown the added starch in the mash.

In terms of a correlation of modification and DP, for the level of modification we see in commercial malts, there is not a strong correlation here. The enzymes are produced early in the germination process and then just take time to breakdown the endosperm of the kernel resulting in modification.

I hope this helps.

Dr Malt

__________________
Dr Malt is offline
 
Reply With Quote Quick reply to this message
Old 09-08-2007, 07:22 AM   #6
Orfy
For the love of beer!
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
Orfy's Avatar
Recipes 
 
Join Date: Sep 2005
Location: Cheshire, England
Posts: 11,853
Liked 69 Times on 52 Posts
Likes Given: 30

Default

Simply.

It's how much of the starch converting enzymes it has.

In other words, it's ability to self convert and covert other starch to sugar.

Orfy is offline
 
Reply With Quote Quick reply to this message
Old 09-08-2007, 01:30 PM   #7
david_42
Feedback Score: 0 reviews
 
david_42's Avatar
Recipes 
 
Join Date: Oct 2005
Location: Willamina & Oak Grove, Oregon, USA
Posts: 25,651
Liked 134 Times on 127 Posts

Default

Excellent discussion DM. First time I've seen currrent numbers for 2-row vs. 6-row. Nature & nurture, who'd have guessed.

__________________

Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"

"I would like to die on Mars, just not on impact." Elon Musk


Last edited by david_42; 09-08-2007 at 01:51 PM.
david_42 is offline
 
Reply With Quote Quick reply to this message
Old 09-10-2007, 07:04 PM   #8
jeff
Feedback Score: 0 reviews
 
jeff's Avatar
Recipes 
 
Join Date: May 2005
Location: Lexington, KY
Posts: 56
Liked 1 Times on 1 Posts

Default

Thanks Dr. Malt, and everyone for your help. I'm studying for the BJCP exam and am trying to wrap my little mind around some of the concepts.


__________________
jeff is offline
 
Reply With Quote Quick reply to this message
Old 09-10-2007, 08:56 PM   #9
Dr Malt
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2005
Location: Pacific Northwest
Posts: 287
Liked 12 Times on 12 Posts

Default

Good luck on the exam!!

Dr Malt

__________________
Dr Malt is offline
 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
diastatic power JLem Brew Science 5 09-27-2009 03:12 AM
diastatic power help pls nutcase All Grain & Partial Mash Brewing 6 04-09-2009 05:09 PM
Carapils and diastatic power hammacks Beginners Beer Brewing Forum 15 06-19-2008 11:05 PM
Diastatic power captainfindus General Techniques 4 02-21-2008 02:30 PM
2-row diastatic power WortMonger Recipes/Ingredients 6 10-02-2007 06:08 PM