Concentrate for RPavilis water recipe

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.
anjony

#1: Post by anjony »

Hi there all, after much reading here, I decide I would give the RPavlis recipe a try. I am using Third Wave Water now but would like to switch or try Pavlis recipe.

I have a couple of questions though.

First, I see it calls or mentions that distilled water should be used. My question can i use RO water or Purified Water to this recipe instead?

Can you please confirm the concentrate recipes below i have found in the threads that people use/suggest. Using my limited math knowledge, I believe Recipe 2 is double the dose of Recipe 1 using it on a per gallon basis, as following:

Recipe 1
9.6gm to 750ml as concentrate. Then use 1 tbsp of concentrate to 1 gallon of water

Recipe 2
97 gram to 1 gallon of water as concentrate. Then use 1 tbsp of concentrate to 1 gallon of water

Thanks in advance

User avatar
homeburrero
Team HB

#2: Post by homeburrero »

anjony wrote:First, I see it calls or mentions that distilled water should be used. My question can i use RO water or Purified Water to this recipe instead?
Any pure water will work. But beware that RO or purified from some poorly maintained kiosk machines may not be very pure, and some may have minerals added for taste. In my local store I can refill jugs with a choice of RO, de-ionized, or 'alkaline' water, but both the RO and the alkaline water have minerals added -- only the de-ionized is essentially equivalent to distilled.


anjony wrote:Can you please confirm the concentrate recipes below i have found in the threads that people use/suggest. Using my limited math knowledge, I believe Recipe 2 is double the dose of Recipe 1 using it on a per gallon basis, as following:

Recipe 1
9.6gm to 750ml as concentrate. Then use 1 tbsp of concentrate to 1 gallon of water

Recipe 2
97 gram to 1 gallon of water as concentrate. Then use 1 tbsp of concentrate to 1 gallon of water
With US Tablespoons (14.8 ml), Recipe 1, with only 1 US Tablespoon per gallon works out to 50 mg/L potassium bicarb. Recipe 2 with 1 US tablespoon per gallon works out to 100 mg/L potassium bicarb.

Professor Pavlis usually recommended 100 mg/L and that's the usual recipe that folks use. He did say that when brewing dark roasts he preferred the taste when using only 50 mg/L. I think the idea behind Recipe 1 is that you would use 1 Tbsp per gallon when making the low bicarb mix and 2 Tbsp per gallon when making the standard mix.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

Versalab: maker and supplier of finest espresso equipment
Sponsored by Versalab
jrham12

#3: Post by jrham12 »

homeburrero wrote:Any pure water will work. But beware that RO or purified from some poorly maintained kiosk machines may not be very pure, and some may have minerals added for taste. In my local store I can refill jugs with a choice of RO, de-ionized, or 'alkaline' water, but both the RO and the alkaline water have minerals added -- only the de-ionized is essentially equivalent to distilled.



With US Tablespoons (14.8 ml), Recipe 1, with only 1 US Tablespoon per gallon works out to 50 mg/L potassium bicarb. Recipe 2 with 1 US tablespoon per gallon works out to 100 mg/L potassium bicarb.

Professor Pavlis usually recommended 100 mg/L and that's the usual recipe that folks use. He did say that when brewing dark roasts he preferred the taste when using only 50 mg/L. I think the idea behind Recipe 1 is that you would use 1 Tbsp per gallon when making the low bicarb mix and 2 Tbsp per gallon when making the standard mix.
Pat, Quick clarification question... I've been looking at the Barista Hustle recipes https://baristahustle.com/blog/diy-wate ... o-bottles/ (link to the updated first version that shows the chart...)

BH calls for 1.68g of Sodium Bicarbonate in 1L of water (which could be modified to 2g of Potassium Bicarbonate in 1L per Professor Pavlis' recommendation, correct?) and then 40.1g of this buffer in 1L of water to get to 50 mg/L of HC03. This would be for either the original BH recipe, the SCA recipe or the Budapest recipe.

Am I correct in reading that 1 Tbsp of recipe 1 above in 1 gallon of water per the above would give the same result of 50mg/L? (That's what I am currently doing to spike my Nestle water per some of your previous posts... [Edit: I think I found the answer as "yes" in your post to F1 on 11/17/19 but I am going to leave this post intact for the below question...]

Also, I've seen on other posts that some were going to try the Mg spike as an experiment to see it's impact on taste but I didn't find where anyone had posted conclusions... If I decide to try the Mg spike in addition, I've noticed that some of the available options for Magnesium Sulfate from brewing supply companies do not show the .7H2O designation. Would that be of any benefit over the standard grocery store epsom salts with the .7H2O designation? If yes, how would the lack of the water content be factored into the calculations?

Thanks!!!
Josh

RyanJE

#4: Post by RyanJE »

Ditch the tablespoon measures! Sounds like you have a scale at least... :D
I drink two shots before I drink two shots, then I drink two more....

jrham12

#5: Post by jrham12 » replying to RyanJE »

Yeah, LOL... It was just convenient to add the spike per gallon that way! But we're looking at getting a whole-home filtration system so we're planning on ditching the nestle 5 gallon bottles and dispenser. So rather than piddle with an analysis of our treated tap water, I'm just going to start mixing my own from distilled. I was looking to confirm that the BH recipes were close to what I was already doing.

My initial plan is to go with Professor Pavlis' recommended 100mg/L of the potassium bicarb and then add just a bit of the Mg to end up with a hybrid Rao / Budapest recipe just to see what the difference in taste is...


Josh

User avatar
homeburrero
Team HB

#6: Post by homeburrero »

jrham12 wrote:BH calls for 1.68g of Sodium Bicarbonate in 1L of water (which could be modified to 2g of Potassium Bicarbonate in 1L per Professor Pavlis' recommendation, correct?)
Yes. 2.0 g of potassium bicarbonate is chemically equivalent to 1.68 g of sodium bicarbonate. (This factor is based on the molar masses: 100.1 g/mol for KHCO3, and 84.01 g/mol for NaHCO3)
jrham12 wrote:Am I correct in reading that 1 Tbsp of recipe 1 above in 1 gallon of water per the above would give the same result of 50mg/L?
It would give you 50 mg/L of potassium bicarbonate, but when comparing to other units you need to be aware that 50 mg/L KHCO3 is equivalent to 25 mg/L of alkalinity as CaCO3, which is the conventional way of expressing this measure. And when comparing to the BH graphs, which use [HCO3⁻] ion as the measurement unit your 50 mg/L potassium bicarbonate is equivalent to 30.5 mg/L [HCO3⁻] ion.

I think it's always best to use a measure of chemical equivalence, like CaCO3 equivalent, when discussing hardness and alkalinity. To convert the BH numbers into CaCO3 equivalents, multiply his [HCO3⁻] numbers by 0.82, and multiply his [Mg²⁺] numbers by 4.12

Note that the standard (full strength) rpavlis recipe would be the 100 mg/L potassium bicarb (50 mg/L alkalinity as CaCO3) - two tablespoons per gallon in the recipe 1 version. Dr Pavlis advised that he might go down to half that in dark roasts for taste reasons. It's expected that high bicarbonate in the water may dull the acids, especially in brewed coffee. In espresso you have far less water relative to the coffee and my opinion is that you can just stick with the full strength recipe.
RyanJE wrote:Ditch the tablespoon measures! Sounds like you have a scale at least...
Scales are great, but high accuracy here isn't all that critical. Whichever is convenient. I use a shotglass to add my concentrate.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

jrham12

#7: Post by jrham12 »

homeburrero wrote:
I think it's always best to use a measure of chemical equivalence, like CaCO3 equivalent, when discussing hardness and alkalinity. To convert the BH numbers into CaCO3 equivalents, multiply his [HCO3⁻] numbers by 0.82, and multiply his [Mg²⁺] numbers by 4.12

Note that the standard (full strength) rpavlis recipe would be the 100 mg/L potassium bicarb (50 mg/L alkalinity as CaCO3) - two tablespoons per gallon in the recipe 1 version. Dr Pavlis advised that he might go down to half that in dark roasts for taste reasons. It's expected that high bicarbonate in the water may dull the acids, especially in brewed coffee. In espresso you have far less water relative to the coffee and my opinion is that you can just stick with the full strength recipe.
Thanks Pat! Just to make sure I understand; looking at the BH numbers, the alkalinity on the Rao recipe would be approximately 65 mg/L HC03 according to the chart... So multiply by 0.82 to get 53ish equivalent CaCO3? (about equal to the standard rpavlis recipe?)

Sorry for being dense here, but Chemistry was never my forte!

Thanks!
Josh

Weber Workshops: tools for building better coffee
Sponsored by Weber Workshops
User avatar
homeburrero
Team HB

#8: Post by homeburrero »

jrham12 wrote:Just to make sure I understand; looking at the BH numbers, the alkalinity on the Rao recipe would be approximately 65 mg/L HC03 according to the chart ... So multiply by 0.82 to get 53ish equivalent CaCO3? (about equal to the standard rpavlis recipe?
Yes, Mr. Perger made it easy for us to calculate the CaCO3 equivalents of each formula because he made those BH concentrates come out to 1 mg of CaCO3 equivalent per gram of concentrate:
"The concentrates are made so that 1g of concentrate equals 1ppm of GH (for the magnesium solution), or KH (for the bicarbonate solution), after dilution in 1L of water."
So the Rao formula, with 75.7 g of the Mg concentrate and 50.1 g of the bicarb concentrate will have a magnesium hardness and total hardness (GH) of about 76 mg/L and an alkalinity (KH) of about 50 mg/L in CaCO3 equivalents. (Note, ppm and mg/L are effectively the same thing for these measurements.)

And here's an annotation of Matt Perger's chart with the axes labelled in CaCO3 equivalents:
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

User avatar
CarefreeBuzzBuzz

#9: Post by CarefreeBuzzBuzz »

homeburrero wrote: Scales are great, but high accuracy here isn't all that critical. Whichever is convenient. I use a shotglass to add my concentrate.
Pat or Ryan, I am curious why high accuracy isn't critical? Although its welcome information.

Usually I am adding 4 gallons of RO to my tank, and my water calculations thanks to @RyanJE, call for 45.4 grams of solution. So I have been trying really hard to make the .4 work using different pouring devices. Are you saying anything in the 45-46 range is fine?

Thanks, Michael
CarefreeBuzzBuzz
___
Artisan Quick Start Guide
http://bit.ly/ArtisanQuickStart

User avatar
homeburrero
Team HB

#10: Post by homeburrero »

CarefreeBuzzBuzz wrote:Pat or Ryan, I am curious why high accuracy isn't critical?
Especially for these recipes where you aren't on the cusp of a scale-forming or corrosive water, a difference 10% or so in the measure will not have an effect on machine health, nor a noticeable effect on taste. An alkalinity of 45 to 55 is fine for the machine and I'd be amazed if the most sophisticated taster could taste the difference in the espresso.

When the SCAA did their taste tests* for the old recommendations they claimed that their expert tasters preferred the (conventionally brewed) coffee right at the SCAA standard when compared to water that had about 15% higher and 15% lower mineral content. But that claim was met with some skepticism, and as far as I know they never showed the data that might tell you if that taste test had statistical significance. Also, when thinking about the effect of alkalinity on percieved acidity, you would expect a lot more effect on brewed coffee than you would on espresso (by a factor of nearly 10) because of the relative amount of brew water in the cup.


* Pg 24 of the 2011 SCAA Water Quality Handbook:
"Acid and body balances were perceived to be off at both 125 and 175 mg/L TDS, and the 150 mg/L TDS brew was rated superior."
This was reportedly using water with the same balance of hardness and alkalinity minerals, done by 2009 SCAA technical standards committee, and was with brewed coffee.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h