70/30 Water

#1: Post by **dilin** » May 4th, 2015, 6:12 am

Moderator moved/merged this post into this topic. It was originally posted in Global Customized Water at home
Water recipe from Five Senses:

https://s3-ap-southeast-2.amazonaws.com ... recipe.pdf

For a more in-depth read,
http://www.fivesenses.com.au/blog/2014/ ... -on-coffee

For those who are really interested, I can post up the journal paper later.

HTH.

#2: Post by **brianl** » May 4th, 2015, 3:05 pm

Moderator moved/merged this post into this topic. It was originally posted in Global Customized Water at home

dilin wrote:Water recipe from Five Senses:

https://s3-ap-southeast-2.amazonaws.com ... recipe.pdf

For a more in-depth read,
http://www.fivesenses.com.au/blog/2014/ ... -on-coffee

For those who are really interested, I can post up the journal paper later.

HTH.

Interesting, I've read differing opinions on whether magnesium or calcium hardness extracts better. This article chooses the previous. So the total TDS of your solution, as read by a TDS meter, would be 100 or 67? (67 would be the 'hardness' plus the alkalinity). I find it interesting that the author says calcium carbonate is confusing/misleading because it might be magnesium but in the summary table of the measurements, uses the term calcium carbonate.

#3: Post by **homeburrero** » May 4th, 2015, 3:59 pm

Moderator moved/merged this post into this topic. It was originally posted in Global Customized Water at home

brianl wrote:I find it interesting that the author says calcium carbonate is confusing/misleading because it might be magnesium but in the summary table of the measurements, uses the term calcium carbonate.

It can be confusing unless you keep in mind that water treatment chemists use a convention of "as CaCO3" when reporting. They take whatever they are reporting and convert it to a chemical equivalent amount of CaCO3. So the water here has 6 ppm Mg++, and zero Ca++, but converted to CaCO3 equivalents the 6ppm Mg++ comes out to 25 ppm total hardness "as calcium carbonate" that you see in that summary table.

brianl wrote: So the total TDS of your solution, as read by a TDS meter

That 'as read by a TDS meter' is an Important distinction, and interesting in this case. For typical drinking water, you can use a standard NaCl-calibrated TDS meter and it will give you numbers that are in the ballpark of the actual TDS. You would expect the TDS to be in the neighborhood of 100 mg/l, because you dissolved 70 mg of bicarbonate and 30 mg of epsom salt in the water. But the TDS meter might read closer to half that because the Epsom contains some water, and the conductivities of NaHCO3 and of MgSO4 solutions are lower than that of NaCl.

May 4th, 2015, 8:05 pm

Moderator moved/merged this post into this topic. It was originally posted in Global Customized Water at home

brianl wrote:Interesting, I've read differing opinions on whether magnesium or calcium hardness extracts better. This article chooses the previous. So the total TDS of your solution, as read by a TDS meter, would be 100 or 67? (67 would be the 'hardness' plus the alkalinity). I find it interesting that the author says calcium carbonate is confusing/misleading because it might be magnesium but in the summary table of the measurements, uses the term calcium carbonate.

Since it's "trade" name is 70:30 water, the TDS I've measured is 70 ppm, using RO water. But as homebuerro (above post) have said, TDS meter only measures specific ions? So it's probably closer to 100 ppm.

Extraction-wise? At 70 ppm, as measured, it tames the over-extraction astringency in the finish for my pourovers. I had been been using RO water then. I then tried pushing the ppm to SCAA recommended 150 ppm using my TDS meter, which sucked out all brightness from the brew. lol

#5: Post by **admcptch** » May 5th, 2015, 7:51 pm

Moderator note: This was the original post of this topic before merging posts from the Global Customized Water topic.

I saw this posted last night on twitter by Marshall (endlesscycles) and found it to be an interesting read which goes along with most of the water discussion I have seen here.

https://s3-ap-southeast-2.amazonaws.com ... recipe.pdf

#6: Post by **brianl** » May 5th, 2015, 8:54 pm

Global Customized Water at home

Conversation was started there.

#7: Post by **endlesscycles** » May 5th, 2015, 9:59 pm

brianl is correct.

#8: Post by **endlesscycles** » May 5th, 2015, 10:03 pm

dilin wrote:Water recipe from Five Senses:

https://s3-ap-southeast-2.amazonaws.com ... recipe.pdf

For a more in-depth read,
http://www.fivesenses.com.au/blog/2014/ ... -on-coffee

For those who are really interested, I can post up the journal paper later.

HTH.

I am really interested. I've been on a water quest for some time. My coffee, brewed with the 70/30 water as I mixed it didn't have quite the qualities I've come to know and love as from my local water source... however, that isn't to say my roasting couldn't be adapted to a different water, or that another water formula and roast together wouldn't be further down the path of the ever better cup.

#9: Post by **homeburrero** » May 5th, 2015, 11:13 pm

Moderator moved/merged this post into this topic. It was originally posted in Global Customized Water at home

I notice that admcptch started a new topic: 70/30 Water today. To avoid having one topic discussion in two places at the same time I think it's best to put any new posts that are 70/30 specific under that topic. Tomorrow I'll look into merging all 70/30 specific posts into to the "70/30 Water" topic. (I think that's pretty easily do-able.)

P.S.
Marshall - Right now you can find that journal article (free of charge!) here: http://pubs.acs.org/doi/abs/10.1021/jf501687c

#10: Post by **brianl** » May 6th, 2015, 10:35 am

I read through the study and had a couple comments:

The article hints that the removal of Calcium for Magnesium removes scaling. I was under the impression that they both cause scale but does the removal of calcium drastically decrease it?

There is a member that is a big proponent of Potassium Bicarbonate (Mostly because it is naturally found in coffee beans while sodium [sodium bicarb] is not?). The study hints that the potassium bicarb has a weaker bond (also less basic) compared to sodium bicarb for the purposes of coffee preparation, which makes it less suitable for use.

I'm confused as to why the author states that MG2+ is best for instant coffee and equally effective as CA2+ for best overall extraction (with the benefit of less scaling). I take it that the conclusion is MG2+ is the best all around but if you only have CA2+, that is equally effective but can induce more scaling.

I didn't really see them quantify what Magnesium rich means and a good starting point in the article. Based on most standards the 70/30 water would be much less in 'hardness'.