Can you use diastatic power to calculate mashing time?

[prankster1590]

Its defined that 100 Lintler is equal to an enzyme population that convert 18.08 umol subtrate (starch)/min.

So if a wort is 100 lintler and it contains a concentration of 372 umol/mL maltose/sucrose (SG= about 1.049)

1 starch = 2 glucose = 1 maltose (I think). So 372 umol = starch is converted in 372/18.08 = 20,58 minutes.

Is this possible?

 

[bracconiere]

temperature of the mash denatures enzymes. i think of it as when their wet and hot, they shake them selves apart. enzymes are kinda like the starch their breaking down, but they need to maintain their twists and stuff to be effective. and their spinning pretty fast at high temp so they unwind, or "denature".


starch is actually, i believe, a LOT bigger then just 3 mols of sugar...sorry if i'm not being helpful, but temp plays a big role on how long these enzymes are actually able to work, like riding a horse to death.....

 

[prankster1590]

Yes denaturing. I know. But it al works fine for atleast an hour at standard sacharisation temps.

I know that starch is more than 2 glucose. But yeah. How else can I estimate reactiontimes

 

[doug293cz]

The rate limiting step in conversion of starch to sugar is gelatinization, not hydrolysis. Gelatinization has to occur before hydrolysis occurs. Diastatic power affects the rate of hydrolysis, but not gelatinization (which doesn't need enzymes.) So, I would say the answer to your question is no. The exception might be for very fine grinds, where gelatinization can occur more quickly.

Brew on

 

[prankster1590]

Yes. But I wanna have some control over the body of the beer and sugar composition of the final wort. So I have to play with temp and time. But its nice to make a first estimation for a mash schedule that might produce what I want. I like a dry light-bodied beer but not to light. Where to start 20 minutes or 25 minutes at 63 C or 64 C. Or 40 minutes. And then maybe so long at 72 C.

There is no guideline for that stuff and experimenting is fun but im one person and would also like to make other beers and things.

 

[hotbeer]

Isn't diastatic power already taken into account by most of the recipes that tell you to mash a this temp over the next?

There are charts and tables galore showing you the ideal temps for a particular grain and malt. But since most all of use a mix of them during the mash, it probably winds up not being too much of a difference since most of the malts ideal number will have us averaging out anyhow and using the 148 to 158°F that most of us hope to be able to maintain with some stability.

Truth is, I'm going up and down in temps. And one part of the pot no matter how well I stir is always hotter or cooler than I desire.

 

[dmtaylor]

The rate limiting step in conversion of starch to sugar is gelatinization, not hydrolysis. Gelatinization has to occur before hydrolysis occurs. Diastatic power affects the rate of hydrolysis, but not gelatinization (which doesn't need enzymes.) So, I would say the answer to your question is no. The exception might be for very fine grinds, where gelatinization can occur more quickly.

I agree with Doug. My own take on it: The amount of diastatic power does not matter with modern 21st century malts which pretty much all have plenty -- exceptions might include dark Munich malt, and so-called diastatic amber and brown malts (which are not very commonly used as base malts). The net conclusion in my view is not to concern yourself with diastatic power, unless it sucks, in which case you'll just want to extend your mash time to 90 minutes or more, with overnight mashing for like 8 hours probably not being a bad idea either if your primary base malt is dark Munich or darker. But anything lighter, from like "normal" Munich and Vienna and upwards, with a good crush and the right temperatures for decent gelatinization in the goldilocks range around 148 F or higher, you're going to get the bulk of your conversion completed in 20-30 minutes, after which the main reason for mashing more than say 30-40 minutes is really just to further simplify the sugars such as maltotriose to even simpler sugars that more yeasts will have no trouble chewing on.

That's my story and I'll stick to it for a while. Cheers all.

 

[Beernik]

The only time I’d worry about diastatic power affecting mash length for a step mash is if your grain bill is between 50L & 30L. Otherwise, I don’t think your mash time is fairly independent of diastatic power and primarily dependent on temperature.

Which is why even though 30L will convert, I never make a recipe that is less than 60L.

 

[bracconiere]

so basically you want to scientifically like all scientifically, be able to make your FG like 1.008, or maybe 1.006, or even 1.004...scientifically and all?

i don't have a premade answer, but it sounds like a fun research project!

one of my first thoughts would be using a refrac and keeping an eye on first runnings, then a quick mash out when ideal?

edit: maybe a comparison between a hydro designed for something else, and the refrac would give an idea of the comp of the sugar?

edit #2: i mean i had beers go to 1.000 without gluco when i sparged with boiling hot water, full open on the valve, so this isn't a completely crazy idea!

 

[hottpeper13]

So I think you should try your idea of the short mash time , only use a refractometer to know when conversion stops. Take a reading at 25 min and again at 35 min , if it goes up your not done.

 

[dmtaylor]

So I think you should try your idea of the short mash time , only use a refractometer to know when conversion stops. Take a reading at 25 min and again at 35 min , if it goes up your not done.

Conversion doesn't stop for probably 2-4 hours. And even then, after maximum starch is converted to sugars, the fermentability of the sugars can change without the original gravity changing. It's complicated!

 

[hottpeper13]

I would think it slows down enough so taking measurements 10 min apart would tell you when it's not worth any more time.
When I do an overnite mash vs a 90 min my OG doesn't change but the resulting wort is more fermentable.

 

[JAReeves]

If I can add a question to this thread, please:

If a recipe's DP goes down below 30 (giving me the red light from Brewer's Friend), does that mean that a 90 minute mash or even an overnight mash will give the base malt enough time to finish conversion?

I have moved to using Maris Otter as my base malt instead of 2-Row, so I am seeing the DP go down on all of my recipes, but my American Stout recipe is the first to drop below 30 and get the red light on the recipe. When I do a 10%+beer, I always do an overnight mash, but this is just a 5%'er.

 

[Beernik]

Below 30L is probably not fully self converting regardless of how long you let it go.

My recommend would be:
- increase the MO,
- add/substitute a touch of 2 Row or Wheat Malt into the grain bill, or
- cut your speciality grains.

Breiss’ White and Red Wheat Malt are 160L and 180L respectively. It shouldn’t take much to kick the recipe over 30L.

 

[JAReeves]

Thank you!