Please help with complex mash schedule

Hey all,

I'm trying to come up with a complex mash schedule for a strong golden ale. I haven't really read too much that coached me on the proper times for each step. I found plenty describing the temperature at each rest, but not much concerning time. So far I have:

Beta Glucanase Rest - 15.0 min @ 110 F
Protease Rest - 20.0 min @ 122 F
Beta Amylase Rest - 60.0 min @ 144 F
Alpha Amylase Rest - 20.0 min @ 162 F

And of course I'm going to finish it up with a 170 F mashout. But I really don't know if those times are ideal or not... I'm most confident about the beta amylase rest because we want a more fermentable beer with less body, but how does the rest look?

Thanks,
Steve

What's your recipe? What are you trying to achieve with the rests?

The grains in the recipe are wholly comprised of Pilsner malt. We are trying to clone Duvel from what we've read in "Brew Like A Monk", which specifies a standard step mash schedule. We want to mash for maximum attenuation and efficiency, and to, well, make something close to Duvel!

I'd say your schedule looks pretty good...the B-G rest may not be necessary depending on your water treatment, but it shouldn't hurt. Unless you are using an undermodified Pilsner malt I wouldn't go past 15-20m on the protein rest. In terms of separate amylase rests I know there are proponents of it, but personally I would just go from the protein rest to a saccharification rest ~150F before mashing out. If you do go with the separate rests you can probably start testing for conversion after 10m at the alpha rest since your mash should be pretty well converted after such a long beta rest.

Thanks, I appreciate your input. That's my first attempt at creating a complex mash schedule. The reason why i added the BG step was because I read that it breaks down cellulose and that allows more starch to be exposed, thus resulting in greater efficiency. And if nothing else, it'll be good experience.

It's also in the acid rest range which, when using Pilsner malt, will help lower your mash pH. It can be difficult to get the mash pH right when using all light grains depending on your water. I would check the mash pH at then end of your protein rest and if it's not 5.2-5.4 then treat it with some acid malt or lactic acid (or other acidifier of choice).

The acid rest may indeed help with the PH if you haven't made an all pilsner malt beer with your water yet. But you can also dough in for the protein rest at 122F and adjust the PH with adic malt or food grade acids. Make sure you have water with low residual alkalinity (read howtobrew.com for more info).

The protein rest (122F) will be very helpful if you plan to add large amounts of sugar to the wort (common for belgians) since you want to get lots of FAN (free amino nitrogen) from the malt since the sugar doesn't provide any and the yeast needs it. 30 min at this temp should be fine.

Since you are going for very high fermentability I would definately step the saccrification rests even more:

30 min at 60*C (I don't know the *F numbers)
10 min at 62*C
10 min at 64*C
10 min at 66*C
30 min at 68*C

mash-out at 75 *C

This can be achieved by starting with a thick mash (~ 1qt/lb) and add boiling water to raise the temp. Using such a step mash ensures that you get the most out of the beta-amylase activity while allowing just enough a-amylase activity to supply the betas with glucose chains to work on. A similar mash is used for Bud Light to make sure that pretty much all the starch is converted into fermentable sugar.

Kai

We use pH Stabilizer in our mash and sparge water, so I don't think that pH will be much of a problem. Well, I modified my mash schedule based up on Kai's suggestions, so even though it's going to take a LOT longer to mash than with a single-step infusion, we're looking forward to it.

We'll be using a HERMS system to bring the temperature up for the steps. And we won't primarily be using the HERMS part of the system for circulation. We'll heat the HLT up to the next step's target temperature with the pump off, then start the pump to heat the mash liquid in the heat exchange coil in the HLT. It should achieve most of the steps pretty quickly, especially the 2 degree C steps.

A mash higher fermentability does take langer than a regular mash since you want to give the enzymes enough time to convert all the starch to fermentable sugars. You can also do further research to see what other brewers do for this style of beer (the Jamil show (thebrewingnetwork.com should be a great resource if he already covered this style). Since I have never brewed this I'm only using what I know about highly fermentable worts and adjunct brewing.


Kai

Kaiser said:

Since you are going for very high fermentability I would definately step the saccrification rests even more:

30 min at 60*C (140F)
10 min at 62*C (143.6F)
10 min at 64*C (147.2F)
10 min at 66*C (150.8F)
30 min at 68*C (154.4F)

Note: I added *F numbers as they're easier on my brain

Click to expand...

Hi Kai - This is an old post but I was curious about something: Conversion takes long at lower temps so I'm curious about the 30/10/10/10/30 times as you ramp up temp, especially the long 30 min rest at the highest temp of 68*C.

Wouldn't something like 90/60/40/20/10 mins give you better conversion?
In other words, start low, ramp up slowly and slowly accelerate the ramp speed.

Kal