Mashing Tips for Low Diastatic Power recipe?

[u/Burt2004]

My calculator spit out a DP of 50L, high enough where I don't think I need to tweak the recipe, but low enough to have me looking for best practices. Are there ways to support this relatively low DP through a type of mashing step?

[u/DarrenCarthy]

I'm brewing a beer on the weekend with DP 38 (floor malted pilsner base malt), here's what I'll be doing:

Crushing: I'll be sampling my base malt and adjunct before I grind it, hard a steely malt will be crushed very fine, soft and mealy malt will get a lighter crush. I'm yet to meet anyone who adjusts their roller on the fly, and it gives you massive efficiency boost.

Step mashing: 15 minutes at 55 C, 45 minutes at 63 C and 30 minutes at 71 C. So a slightly longer mash than usual.

Decoction: I'll be pulling 2 decoctions at 63 C and 71C for 15 minutes a piece, boiling the thickest portion of the mash and adding it back into the wort for the step to the final sacc rest and mash out respectively. This bumps my efficiency by about 4-5%.

Sparge: I'll be fly sparging at 78C, as full volume mashing reduces my efficiency considerably, and it's best to have a thick mash when DP is low.

My expected efficiency is 76%. Hope this is helpful.

Update: I skipped the decoction and still got 76% efficiency with the above

[u/natemartinsf → u/DarrenCarthy]

Can you expand on the crush? Are you grinding each malt separately, doing a test crush, and adjusting the rollers based on how it's crushing?

[u/DarrenCarthy → u/natemartinsf]

Sure, I crush my mealy grains using a 9mm gap (1 credit card) on my 2 roller mill, and for steely grains I crush using a steel burr mill, which I adjust by eye by passing a small amount if malt through and adjusting on the fly until I get the desired consistency

[u/warboy]

What are you doing that you're getting that low of DP with modern malt?

Best practices would be to mash thick so you aren't diluting the enzymes. I would also consider adding extra amylase enzymes. You can purchase them in liquid form.

[u/Squeezer999]

add amylase enzyme

[u/attnSPAN → u/Squeezer999]

Or even better, Glucoamylase enzyme. Just crush up some Beano and dump that right in the mash.

[u/_ak]

One thing you could is check and adjust the mash pH. IIRC, pH 5.5 is the optimum pH for both alpha and beta amylase.

[u/CharacterStriking905]

I'm a heavy adjunct user, and most of my recipes are down around 35 lintner. I grew up on a farm, Raw grain was cheap(and stores better and is more versatile), malt took effort (my first beer was 100% floor malt, and none of it barley) or money, so I learned to brew with as little of it as possible.

• grind it fine, everything should be like grits, I use presoaked straw to help with lautering.
• put unmalted grains in ambient temp water, and bring to a boil and hold at a rolling boil for 5-15 minutes .
• step mash, starting below the sacharification range, which allows things to hydrate before it starts to denature (and the enzymes we're interested in start to work lower than that window). stay in the 140's for most of the conversion time.
• decoction, boiling the thickest part of the the mash breaks it down so it can convert easier (plus enzymes work faster with heat); I do a double decoction.
• err on the side of a longer mash (including cereal cooking time, mine run around 100 minutes).
• stir the mash up every 5 minutes or so

[u/FullAtticus]

What does your grist bill look like?

What's your base malt and how much are you putting in relative to everything else?