using adjunts/salts while mashing and boiling

[Mark Kessell]

i've read some of the "how to brew" site about adding salts/chalks to alter the mineral composition of the mash water.

HOW TO BREW goes on about chalk being used to "harden" the mash water. what does that mean, and does it mean that i can use it in most brews? or am o best to keep that to dark brews only? and if so, why? do i need to do it at all?

i also understand that in some cases, the extra mineral content (of certain compounds) accentuates the flavours of the beer. but if the PH of the water is neutral, and the mash PH is between 5.2 and 5.4, why use it at all?

also, which salts etc, modify the PH of the mash?

[denimglen]

If you go to the brewingnetwork.com and listen to their show's on water treatment it'll answer your questions better than I can. But I'll give you a brief run down.

There's two reasons to adjust water - pH and flavour.

The principle flavour ions in the water are SO4 and Cl, and to some degree Na. SO4 accenuates bitterness and Cl sweetness/maltiness.

Ca (and Mg a little) will react with compounds in the mash to acidify the mash, therefore if you're too high on your mash pH you can add CaSO4 (gypsum) or CaCl to reduce it. CO3 will raise pH, so here you can use CaCO3 (chalk) or NaCO3 (baking soda)

Darker beers will have a lower pH mash, lighter beers a higher pH mash.

pH of the brewing water plays very little role in the pH of the mash as buffering compounds are coming in to play here. More important is the ion levels of your source water. Hit up your water supplier for these, the data you need is the levels for Ca, Mg, Na, SO4, Cl, HCO3.

[Doublehoppy]

Denim, do you have the figures for Auckland? I've got an analysis sheet I got from watercare or someone a couple of years ago but it's missing some of the figures. I can upload it next week once I'm back at work, but the levels for the relevant chemicals are (all ppm): Ca 8.55, Mg 2.44, Na 3.77, Cl 20.1. Nothing for SO4 or HCO3.

[denimglen]

That's not too much different to mine.

There's about 4 different supplies for the whole of AK, depending where you are you'll be on one or a mix of two.

The figures I have for east auckland are Ca - 9.3, Mg - 1.8, Na - 11.2, SO4 - 10.9, Cl - 16.4, HCO3 - 29.6.

If you email metrowater or whatever they're called and let them know where you live they'll send you an analysis, just make sure you mention which figures you're after.

Hope that helps.

[Doublehoppy]

Thanks, yes it does.

I live in Grey Lynn. When I asked about the supply a couple of years ago I was told that the analysis isn't all that different between them, as the soil etc in the different catchments is much of a muchness. Also a suburb isn't always supplied from the same catchment.

As you suggest I'll email metrowater but I'd be surprised if they were materially different to your figures.

[Raffe]

Did you have any luck with Metrowater?

I also live in Grey Lynn and am beginning to think about treating my water. I would greatly appreciate any info you may have on the mineral analysis! If not I will contact them myself.

[Haish]

Watercare are who you want for Auckland water analysis. Here is the latest report (2009).

Where your supply comes from depends on which suburb you live in. There is a map somewhere on watercare's website (or there used to be) that shows the distribution from each of the treatment plants. I know the Eastern suburbs are 90% Ardmore and 10% Waikato. I suspect Grey Lynn would be the same.

Auckland's water is very soft as it is essentially captured rainwater. A good blank canvas for water additions...

[Raffe]

Thanks!

So it would be a matter of taking the average figures for Ardmore and Waikato from the report, multiplying by 0.9 and 0.1 respectively, and adding together....

I couldn't find the map on the Watercare site you referred to, it must have been removed.

[Pilgrim]

Beers around the world are characterised by the quality of their water. Pilsen has very soft water with hardly any mineral content, Burton on Trent in the UK has some of the hardest water in the world, great for English Bitters.
You wouldn't be able to brew a real English Bitter in Pilsen, nor a Pilsener in Burton on Trent, not without some drastic water treatment anyway.
Software like BeerSmith provides the ability to dial in your own water profile and then play around with chemical additions in order to match your target water profile.
Wanganui has always had quite hard water, but with the recent soft water bore coming online I'm going to have to adjust the water for English Bitters. I rang the Council and they actually sent an engineer around to get a sample from my kitchen tap to send away for analysis. Now that's the sort of service you only get in the smaller centres :-)

[Mike Neilson]

Just Stumbled on this after looking at Thornbridges website (I wounder when we will see some Jaipur or Kipling in NZ)

Varying amounts of five different salts are used and these are Calcium Sulphate (gypsum), Calcium Chloride, Magnesium Sulphate (Epsom salt), Sodium Chloride (table salt) and Sodium Bicarbonate (baking soda).

What’s the point of using these salts? As I’m sure you’re aware, beer is mostly water, usually between 90 and 94%. Water is a great solvent and all of these brewing salts dissolve in water (to a greater or lesser degree) and undergo a process called dissociation. Water is a molecule that exhibits polarity, meaning that the hydrogen and oxygen molecules have charges. It is these charges that allow our brewing salts to break up into their ions. For example, if we were to dissolve sodium chloride in water, the positively charged sodium ions (Na+) would be attracted to the negatively charged oxygen ions (O2-) in the water and the negatively charged chloride ions (Cl-) would be attracted to the positively charged hydrogen ions (H+) in the water.

This is all fair and well, yet how does this help the brewer? The fact that these salts dissolve allows all of these ions to affect certain parts of the brewing process. Calcium is important during mashing. It boosts and stabilises enzyme activity during mashing (both by pH reduction and heat protection of enzymes), as well as aiding starch gelatinisation and lautering performance. It also binds with phosphate ions (from the malt) which facilitates a decrease in pH in the boiling of the wort, inhibits too much colour formation, aids the coagulation of proteins and effects bitterness extraction during boiling. It is also important in fermentation performance and the flocculation of yeast cells and helps prevent haze. A pretty important ion!

Magnesium also helps to lower the pH of the mash but more importantly, it is important as a cofactor for yeast during fermentation. It’s important to be aware that magnesium ions can contribute harsh bitterness to a beer though, so these salts are always used with caution!

Carbonate or bicarbonate ions are also very important in brewing. These play a major role with regard to the pH of the water. Remember that the enzymes that are present in the malted grains themselves all work at an optimum temperature and optimum pH, hence it is essential that these are balanced correctly. These ions tend to move the water more towards a high pH (alkaline) which works in the favour of dark beers, where the malts used often contain compounds that can be quite harsh or astringent. The ions help to balance out these acidic dark malt characters. However, in well-hopped beers, alkaline water tends to result in a rather intensely bitter beer.

Sodium affects the perceived flavour of the beer by enhancing its sweetness. Kind of weird when you think that we use salt on our food to increase its saltiness! The only thing is that you have to be careful when using too much of this in the presence of sulphate ions. Sulphates give crispness and dryness to the palate when used correctly, but can tend towards salty and harsh (and laxative!) if over-used. If you have too much of both sodium and sulphate ions in a beer you also get an unpleasant harshness, so again, it comes down to balance. Chlorides also give a rounded, full bodied beer and are beneficial when used in darker, sweeter beers.

[Mark Kessell]

wow. thats a pretty cool explaination.

thanks mike.

[Mike Neilson]

I thought so myself!! Those boys must be good!!

[Stu McKinlay]

Mike -
This might explain when:
http://www.thornbridgebrewery.co.uk/thornbridge_news.php

Read the second to last paragraph...