Multi-Rest Mash and Water Building

[bootney]

I'm doing a multi rest mash for twenty minutes at 104° and then the sacch rest for sixty minutes at 153°. I use distilled water and need to build from scratch so my question is do I even the salts out over both my strike water and the mash infusion or do I just add them all to one or the other. I tried asking in the brewing chemistry forum but there's not that much action there. Thanks

 

[remilard]

It seems simplest to just treat all of the water at once. The common salts other than chalk will dissolve fairly readily and my recommendation for chalk would be to never add it unless you have already doughed in and observed a too low mash pH (pretty good chance this will never happen) and then you can add it directly to the mash.

My water has RA = 12, so basically distilled from a pH POV and the lowest mash pH I have ever recorded without acidification is about 5.4 which is right about where I want to be anyway. Note that the precision pH strips manufactured in germany appear to systematically measure about .3 pH low.

I guess you could add so much calcium sulfate and calcium chloride that you would then need chalk but then I would ask what you are doing that for (the answer is probably that you are emulating some city's water).

 

[kryolla]

is that an acid rest at 104* if so why are you doing that and messing with salts, I would think your PH would be all over the place

 

[bootney]

My goal is not to mimic a certain water exactly but more less to have proper RA for a Porter with an SRM of 22 as well as a neutral chloride to sulfate ratio. I got the idea for the 104 rest from 14.3 Doughing-In to help boost the yield. I wanted to know if I should build the water before the 104 rest or for the 153 as I will be using distilled water. The choice to use Chalk and Baking Soda was to help boost the RA. I've been using EZ-water-calculator to help build the water from scratch. Thanks for the replies guys and look forward to your responses.

 

[remilard]

Well that depends on what you believe is happening at 104 (40 C). For the record, this is where I dough in and I enthusiastically support it.

Beyond what I believe happens*, I use this rest as an opportunity to test and adjust the pH before I am at the higher rests. My experience is that if your water has a positive (or low negative) residual alkalinity, you can brew just about any beer including stouts and porters without have to ever raise the pH (for pale beers you will have to lower it). Search for posts by AJ Delange on the brewing network forums or google for his website to find out more about this. So what I would do is this (assuming starting from distilled).

1. Add enough calcium, probably as calcium chloride for a porter, for enzymatic cofactor purposes. 50 ppm is plenty, I use 30 ppm all the time (tap water) with great fermentations and great yeast clearing.

2. Use yeast nutrient since your distilled might be lacking in trace nutrients.

3. Once you have doughed in at 104, check the pH (remember the .3 pH bias in the precision strips if you use those, consider a pH meter if you can afford it). It should be 5.2-5.8 and I personally shoot for less than 5.6. If it is low (it won't be) add a little chalk and wait a few minutes and check again. Only increase temp to protein or sacch rest once your pH is good.

*For what I believe happens at this rest, buy the late Dr. George Fix's books or search for his posts on HBD.

 

[dstar26t]

If you are going to start paying attention to mash pH, do yourself a huge favor and get a pH meter. I recommend the one Kaiser recommends (seen here). I never could use the strips because I'm color blind but they also don't seem nearly accurate to me. I like to keep the mash pH between 5.3-5.4 and try to keep the final runnings under 5.7. You can acidify your sparge water to 6 to keep your final runnings pH down. When you first start playing around with mash pH, it's a great idea to do what remilard is suggesting. Once you get the hang of it, you can add everything together at sacc rest temp unless your recipe or process calls for other rests of course. Don't add salts to the strike water. Add them to the mash and boil kettle.

 

[bootney]

I'm starting to question if I should just skip the 104* rest and just have the water set to go for the 153* sacch rest. Using the EZ Water Adjustment Calculatorhas helped me to understand additions and what not, but I fear that if I use a multi rest with distilled water it's going to require more attention on my part to ensure that the pH is appropriate. Is it safe to assume that if I used unchanged distilled water for the strike water that the mash would start to develop it's own pH and the previous calculated additions using the calculator may no longer be relevant because the mash has already started to form it's own pH?

After reading what Palmer had to say about the 104* rest I'd like to use this rest but it looks like it may be more trouble to deal with especially since I'm trying to build water for the first time.

One again thanks for the replies and the insight. It's a great deal of help.

 

[kryolla]

I would skip the acid rest and brew a light SRM beer until you get more familiar with salts and PH

 

[dstar26t]

It's better to play with pH and be off at 104 than it is at 153. pH won't change much during the ramp up to 153. You will get some pH drop from the acid rest but if you're using all distilled you will probably need some Ca or acid (depending on the color of the beer of course).

I use Kaiser's spreadsheet with great results. No spreadsheet I know of accounts for an acid rest so you'll have to go by experience. I've never used an acid rest for pH manipulation, I just add acid, it saves time.

Like Kryolla suggests, try to keep it simple until you've gained some experience with using the salts/acid/acid rest/pH meter. Like I said earlier, I highly recommend getting a pH meter. Then brew one of your normal recipes and track the pH throughout the process without changing anything. Then brew it again with salts/acid/acid rest to see what happens with the numbers and flavor.