Decoction mash to lower mash pH at saccharification rest?

[seventhmagus]

Hey everyone. I was planning on making a big barleywine, and I live in an area where the water is fairly alkaline (Tucson).

I want to make the beer out of 100% 2-row barley and boil for at least 5 hours -- I want to experience Maillard products like I never have before.

The sticky says "you will have to add some sort of acid to your brew" and I was wondering if any of you guys had had luck with using a decoction mash to lower your pH. I would rather do a decoction if it means avoiding adding lactic/phosphoric acid to my brew, but if it isn't effective then I wouldn't go down that path.

The other thought I had was adding pitted (de-pitted?) plums to the mash to lower pH, but I'd rather do that on a subsequent brew.

Thanks for all your thoughts.

p.s. it is BIAB in a 5-gal kettle, I'm thinking single batch sparge in another pot, english style with WLP007 english ale yeast, and hop schedule TBD, but I have a pound of Phoenix, EKG, Willamette, Fuggles, Bullion, and Bravo each.

 

[Gavin C]

Can't see you having much wort left to taste anything in after a 5 hour boil starting with a max preboil of 4.5 gallons in your 5 gallon pot .

Sounds like your plan needs some retooling.

 

[seventhmagus]

I was going to add RO/Deionized water as needed to prevent it all from boiling away. I think if I didn't it would be malt caramel.

 

[Yooper]

Decoction won't lower your mash pH. The decoction is pulled after you mash in.

Using RO water would be a good start, but you still may need some acid to get a mash pH of 5.4 or so. You could use a bit of acid malt (sauermalz) if you have an aversion to using lactic or phosphoric acid.

If you add water as you boil, you will dilute your beer tremendously, and then lower your efficiency to practically nil, as well as lose any maillard reactions gained by a long boil.

I think this plan needs some thought to make it work, from getting a proper mash pH to having a proper boil volume and not diluting the beer so significantly with water.

 

[seventhmagus]

The decoction is pulled to raise to a saccharification rest, which is where you're going to be more worried about the pH's on your amlyase enzymes and the tannins present in the entire batch of grain (granted, you get some higher tannin extraction from a decoction, but better to have the whole rest at the right pH).

Adding water does not reduce the amount of sugar I have collected.

Replacing water to keep a constant volume does not dilute wort

Water does not return Maillard products back to sugars and nitrogen.


Yes I would need a source of acid. Sorry if I'm being rude but I'd like to know if anyone has had experiences with a decoction lowering their pH into an appropriate range for their saccharification rest without adding additional acid compounds

 

[Yooper]

I don't know how many decoctions you've done, but you have to have the mash pH in range BEFORE the decoction, as you still are at conversion temperatures and you can extract excess tannins if your wort pH is too high and at over 170 degrees. Decoction is not a tool to hit a proper mash pH- the proper mash pH must be hit before pulling the decoction. You could certainly do an acid rest first, and then decoct to saccrification rest temperatures, but you still need a proper mash pH in the mash.

If you start with 4.5 gallons of wort, you will not reduce your sugars, but you will not have a great efficiency diluting with 50% water. Maillard reactions after 5 hours of boiling will be impacted by constantly adding cold/room temperature water.

I will step out of this, as certainly you seem to be set on doing this regardless of any science based reason to not do so.

 

[giraffe]

Ive done hundreds of decoctions, and never measured a significant change in mash ph to the main mash before and after. I adjust to the correct mash ph before pulling the first decoction. I, too, am a bit confused on how it would potentialy lower mash ph.

 

[ArcLight]

What about a 4 hour acid rest at 95F, to produce phytic acid.

 

[giraffe]

also why not do a 2nd batch sparge and top off with the second runnings instead of water, your efficiency would be higher that way, and you have the boil time to make it work.

 

[seventhmagus]

I don't know how many decoctions you've done, but you have to have the mash pH in range BEFORE the decoction, as you still are at conversion temperatures and you can extract excess tannins if your wort pH is too high and at over 170 degrees. Decoction is not a tool to hit a proper mash pH- the proper mash pH must be hit before pulling the decoction. You could certainly do an acid rest first, and then decoct to saccrification rest temperatures, but you still need a proper mash pH in the mash.

If you start with 4.5 gallons of wort, you will not reduce your sugars, but you will not have a great efficiency diluting with 50% water. Maillard reactions after 5 hours of boiling will be impacted by constantly adding cold/room temperature water.

I will step out of this, as certainly you seem to be set on doing this regardless of any science based reason to not do so.

You don't get much tannins at lower temperatures, that much is fairly well-agreed upon. I don't have any experience with high pH for lower rests (below 140 or so). I'm not going to be diluting with 50% water. I plan on using an electric kettle to pre-heat water before adding it to the boil to minimize reducing the temperature.

I have gotten 90%+ conversion efficiency with BIAB, and expect to do so again given a good pH (previous brews have had roasted and crystal malts), with a total efficiency of around 70% with no sparging.

To address what I believe is your most relevant concern, I don't have experience decocting, but I've heard that your pH drops by around 0.3 to 0.4 and that this needs to be accounted for. I don't think decoction brewers add slaked lime, and I know it's a technique used by traditional German brews in areas with very pure water. Even in pure water, acidification is necessary. AFAIK, not every light German beer (koelsch, pilsner styles etc) uses Sauermaltz.

Also, just because conversion happens at lower temperatures doesn't mean that it's going to ruin something if the pH is too high -- as long as it isn't sufficiently out of whack to denature the enzymes (I think that would happen closer to 8).

 

[seventhmagus]

Ive done hundreds of decoctions, and never measured a significant change in mash ph to the main mash before and after. I adjust to the correct mash ph before pulling the first decoction. I, too, am a bit confused on how it would potentialy lower mash ph.

I think Kai troester had some data with this but there was not a lot I could find. He mentioned he found it was much more significant than acid rests.

 

[lhommedieu]

Just boiling mash will probably not lower pH sufficiently for your purposes. An acid rest will lower mash pH if the grain still has phytase in it. However, this will generally take you to within the pH range that favors alpha amylase; to get to a pH range that favors beta amylase, you will probably need to add saurmalz. The reason that 5.4 pH is mentioned, is that it is between both ranges. It may be better to learn the process with a lager that does not require such a long boiling time.

I've been learning decoction method for the past year or so, thanks to posts by and conversations with VladOfTrub on the forum. I've made plenty of mistakes and have learned from each of them. I believe that my last batch, a Marzen, puts me over the finish line with respect to whether I am starting to understand the process.

Look to Noonan's Brewing Lager Beer and New Brewing Lager Beer for a concise description of the decoction method.

 

[giraffe]

I think Kai troester had some data with this but there was not a lot I could find. He mentioned he found it was much more significant than acid rests.

The most ive ever seen is 0.1. Which could be measurement error, or from the acid rest. In the real world I dont think you'll find that to be the case.

I do have very soft water out of the tap. I dont know if it matters.

 

[lhommedieu]

Hard water can buffer pH.

I'm still learning the decoction method, so please allow for mistakes as I think out loud and work my way through the process. My experiences so far:

Using my water, which is pretty soft, and Poland Spring water, which is even softer, the malt that I was using last year had an inherent pH of 5.8 after I doughed in and let the mash sit for an hour (or longer). Raising the temperature of the mash to 95F and performing an acid rest dropped it down to pH 5.6, which is within the range for alpha amylase, but still too high for beta.

This is why, if you wanted to brew using a step mash or a basic, single decoction method, you would use saurmalz to further drop the pH to 5.3 or so - a value in which both alpha and beta can work.

You could also do a tri-decoction, the description of which is given on several threads on the forum.

 

[seventhmagus]

Using my water, which is pretty soft, and Poland Spring water, which is even softer, the malt that I was using last year had an inherent pH of 5.8 after I doughed in and let the mash sit for an hour (or longer). Raising the temperature of the mash to 95F and performing an acid rest dropped it down to pH 5.6, which is within the range for alpha amylase, but still too high for beta.

.

Using the hard water I have here, the water would raise a mash with inherent pH of 5.8 to 6.0. That estimate of 1% Sauermalz for every 0.1 pH means i'd need about 1 in 12 pounds of grain to be Sauermalz.

I don't know how effective an acid rest would be. I suppose I could always get some pH strips and test it with a few ounces of grain. I think ~4 hours would be my limit on what I'd be willing to do. I don't fully understand the enzymes at work in it.

 

[lhommedieu]

Using the hard water I have here, the water would raise a mash with inherent pH of 5.8 to 6.0. That estimate of 1% Sauermalz for every 0.1 pH means i'd need about 1 in 12 pounds of grain to be Sauermalz.

I don't know how effective an acid rest would be. I suppose I could always get some pH strips and test it with a few ounces of grain. I think ~4 hours would be my limit on what I'd be willing to do. I don't fully understand the enzymes at work in it.

No worries. You can dilute your water with distilled water, use spring water, or treat the water to make it softer. The middle solution is probably the easiest, although it will cost you about $12 for a 5 gallon batch.

A lot depends on the grain. If the grain that you are using does not have the phytase kilned out of it, an acid rest can be effective if you are using soft water.

http://www.howtobrew.com/section3/chapter14-2.html

https://byo.com/stories/item/1497-the-science-of-step-mashing

http://www.morebeer.com/articles/treating_homebrew_water

In the fall I'm going to invest in a RO system as I'm getting tired of taking Poland Spring bottles to the recycling center, lol.