Step mashing technique using electric HERMS

[andrewb_1985]

Hello,
My current Brew setup consists of 3 20gal pots with electric heaters and Herms coil.

With my setup when i step mash, it takes considerable time to increase the temp of my wort between steps. I have only done rests at 122 for protein rest so far and it takes me about 45 mins to raise from 122 to 155 where I normally sit for an additional hour before raising again for mash out. With a planned Hefe brew coming up I plan to use a Ferulic acid rest for the first time at 112F.

So my question is if I sit at 112 for 20 mins and then ramp straight to 168 over probably 1.5 hours for mash out, is there any gain anymore in staying at 155 for any amount of time?

And also is there any gain to a more rapid temp rise between steps? Ie if I added direct flame under mash tun to ramp more quickly. Because the way I see it with such a slow rise in temperature I'm basically doing protein, acid, b-amylase, a-amylase rests all in one.
Thoughts?

 

[IslandLizard]

If you're staying in the 146-158°F (sacch rest) long enough you will get complete conversion. Most well hydrated grist (like yours will be) converts in 15-20 minutes. You could do a conversion test with a drop of Iodine with a small sample on a white plate, when you reach 154F, and decide to leave it there for a bit longer, before proceeding to mashing out.

With a slow ramp up, like yours, expect a very well fermentable wort, with low dextrin (body) content.

 

[IslandLizard]

I'd be wary of direct heating the mash tun as the wort underneath your false bottom may get overheated, deactivating enzymes.

I'm surprised it takes that long with your HERMS. Is the HLT at high enough temps, like 180-200F?

 

[andrewb_1985]

No, I've found that my hlt at about 3 degrees warmer than my mash holds the mash perfectly. So my controller when set to 155 in my mash tun controls my hlt to about 158.

That being said I see your point. With a higher hlt temp i could control the mash temp by varying flow rate and with higher flow at the higher temp would raise the temp much faster. but wouldn't that effectively do the same damage to the enzymes in my wort travelling through there?

 

[IslandLizard]

During a rest, yes, keeping the temp constant is the goal.

But when stepping up to the next rest temp, you'd need to increase the HLT temp. 170F is very common as that is around mashout/sparge temps. But you could go higher, then add some cold water to bring it to sparge temps, right before sparging.

That being said I see your point. With a higher hlt temp i could control the mash temp by varying flow rate and with higher flow at the higher temp would raise the temp much faster.

You got it! The higher flow rate prevents the wort from getting too hot. You'd measure the temp of the wort at the exit of the HERMS coil, making sure it doesn't exceed your next step's temperature.

 

[andrewb_1985]

You got it! The higher flow rate prevents the wort from getting too hot. You'd measure the temp of the wort at the exit of the HERMS coil, making sure it doesn't exceed your next step's temperature.

Yeah that's one mistake I made with my fabrication. I put the RTD for the mash tun in the mash tun and not on the inlet. It took me a few brews early on to figure out how to compensate. But basically I can brew with just the hlt temp. I've learned over time what the mash is doing based on the hlt. And I always use a secondary thermometer in the tun just to be safe.

 

[IslandLizard]

Can you move the RTD?

One of my brew friends has a 3 kettle, 20 gallon rig with an eHERMS on the mash tun. It's a small 5-6' HERMS coil in a (small) 1 gallon pot. The water in the gallon pot is heated with a cheap 1500 or 2000W element, while wort is recirculated through the coil at a relatively high speed. There's a PID sensor on the outlet of the coil that controls the 2000W element. The response is rather quick because of the small pot volume. We've brewed with several step mashes and it works really well. Something like that would be my setup of choice. The HLT is basically for heating strike and sparge water.

I think raising the HLT temps and increasing your wort flow will make your system much more responsive.

 

[andrewb_1985]

Can you move the RTD?

I cant really move it as id have a hole in my pot. but i could simply add another one and not use the old one anymore, but I dont think that is causing me much grief really.

I think raising the HLT temps and increasing your wort flow will make your system much more responsive.

My system uses a 25ft copper coil and has to sit in 8gal on water in order to be fully covered. This is probably the reason it takes so long to heat all that water with 5500W element. The issue with running higher temps and higher flow in my hlt is it WILL heat the wort up as that coil is very efficient. if the water is 170 in the hlt in no time at all the mash will be close to it. Really what i would need to do is heat the hlt faster with either a second element or direct fire.

At any rate, my OP was more about the effects my systems performance will have on my brews and how i can use it most effectively as is. I will however see if I can come up with a way to make my system more user friendly

 

[IslandLizard]

At any rate, my OP was more about the effects my systems performance will have on my brews and how i can use it most effectively as is. I will however see if I can come up with a way to make my system more user friendly

With your system as it is, you'll have a harder time to change your wort profile during step mashes, as it stays much longer in the lower range. The resulting wort will always be very fermentable. If you want less fermentable, more dextrinous wort, don't do step mashes, hit it at 156-158F and let it be for the entire mash duration or do a large infusion. I've made dextrinous soup by starting high for 10', deactivating most beta amylase, then dropping the mash temps to let alpha go to town.

 

[andrewb_1985]

With your system as it is, you'll have a harder time to change your wort profile during step mashes, as it stays much longer in the lower range. The resulting wort will always be very fermentable. If you want less fermentable, more dextrinous wort, don't do step mashes, hit it at 156-158F and let it be for the entire mash duration or do a large infusion. I've made dextrinous soup by starting high for 10', deactivating most beta amylase, then dropping the mash temps to let alpha go to town.

Thanks a lot for your input. With my setup do you think I would benefit from a maltodextrin addition? Or is there anything else I can do to increase body?

 

[IslandLizard]

Thanks a lot for your input. With my setup do you think I would benefit from a maltodextrin addition? Or is there anything else I can do to increase body?

Although you could, I would avoid using maltodextrin.
Instead, you could leave some base malt behind (say 10-30%) until your mash hits 158-162F. Then add it and leave for 20-30' at those temps. That's the optimal to high range for alpha amylase, which creates lots of dextrins, while beta (which gnaws off the ends) is slowed down. There are other, possibly better methods.

 

[andrewb_1985]

Although you could, I would avoid using maltodextrin.
Instead, you could leave some base malt behind (say 10-30%) until your mash hits 158-162F. Then add it and leave for 20-30' at those temps. That's the optimal to high range for alpha amylase, which creates lots of dextrins, while beta (which gnaws off the ends) is slowed down. There are other, possibly better methods.

I like that idea I think I will try that in a couple weeks when I brew again. Funny, that seems so simple but never even crossed my mind!