pH test strips dont work with my water

[BlackRocksBrewery]

Can anyone help? I use narrow range pH strips from several companies including Johnson, Watman BDH, Merck etc and all show a very low reading during my mash. The indication shows the pH to be below 4.6 even with water treatment recommended by Murphy's of Nottingham.
I suspected the water from the tap and when tested using the strips I get an indication of around pH5. I do have very soft water and the beer tastes good but I have no idea of my mash acidity and therefore feel I have no control when any changes occur to grain or water.

I asked several recognised laboratories including Severn Trent to test my tap water and all tell me that it is over pH 7. Murphy's gave a lower reading of pH 6.

I then suspected the strips (even though they were from 3 different companies). Johnson retested their strips and confirmed that they are within specification. Also when I test water from approx 2 miles out of my area the strips give a reading of around pH7.

Can anyone suggest what is happening?

Best wishes

Stephen

[Eric]

It does seem strange. Take no notice of the pH reading from your tap water but I'd have expected Murphy's calcium additions would have got your mash in the right region although I've no experience of brewing with soft water. You are leaving the strip in a full minute or until it doesn't change colour any more?
Can you say what types and quantities of grain you use, what stage you measure pH and what liquor/grain ratios?

[BlackRocksBrewery]

Eric thanks for your comments. I only checked the tap water after finding very low readings in my mash. This confirmed that something strange is happening with my water and the pH strips. The narrow range pH paper should indicate a light mustard colour for 4.5pH and red/purple for 6.2pH. When I test my tap water I get a dark mustard colour. Testing water from a mile away from home or local spring water I get a dark purple indication ie over 6.2pH.

Initially I only left the strips in the mash for the 3 seconds (as recommended by manufacturers) but later left them in for over a minute. This made no difference to the indication colour.

When mashing I use 15litres water. A typical grain mix for my pale ales is 4kg Fawcetts Maris Otter pale malt & 250g crystal malt.

As I said my beers are tasting good and I trust the salt additions supplied by Murphy"s which for 25litres are:- 9g calcium chloride flake and 11g gypsum. Also add a half cambden tablet. I measure the pH once the mash has been mixed and the temperature has stabilised. This is within a few minutes of mixing.

Stephen

[greenxpaddy]

I have found these very reliable

http://www.the-home-brew-shop.co.uk/aca ... of_50.html

Have you tried this make?

Also how do you store them - in the sealed original container?

[greenxpaddy]

A couple of other thoughts...

Do you clean your MT or HLT with starsan or another acidic cleaner....in which case you may want to rinse them fully afterwards, even though starsan is no rinse acidic residues would affect things.

If the water is actually normal into your house then something is affecting it once it gets into your house. I am thinking - hoses, receptacles. Did the water company test samples you provided or did they take their own - and did all of them have the same sample water at the same time from the same source? I am surprised Murphy were a whole point out

I think your ph strips are no good because your beer tastes good. It wouldn't if the mash ph was too low.

[BlackRocksBrewery]

Thanks greenxpaddy, the strips you have shown on the home brew website look identical to my Johnson's ones. I keep them in sealed containers, asked the suppliers to check them, used others from BDH and Merck. In the past I have used strips from Hop and Grape. I have also taken samples from a hotel and 4 other homes within a mile of my house. All the papers from all locations show similar results. As I said before the water from outside this area shows a reading around 7pH.

The water samples provided to the various laboratories were not taken at the same time but all were taken from my tap.

When I clean out my mash tun and any associated equipment I am pedantic about rinsing.

Stephen

[Eric]

Would tend to accept your readings as being accurate from what you've described. Might I make two suggestions?.....

1. Reduce the amount of water you use to mash to say 10 litres. This will concentrate the salt additions and may improve your mash pH.

2. Add some bottled mineral water. My water is very alkaline, ground water from magnesian limestone, such that it has about ten times as much bicarbonates as is ideal for brewing pale ales. You can buy very similar water from a private bore hole a few miles distant and it would interesting to see what might happen if you used it (or something similar) for 10% of your brew water as well as your salt additions. This water is Hadrian Spring Water and I know it is stocked in our local Asda. This site http://www.contractbottlingltd.co.uk/ gives a little information. At the very least it would reduce the acidity a little.

Good luck.

Oh, and give the mash a few more minutes to get going before you take your pH reading.

[BlackRocksBrewery]

Eric

Really appreciate your input. I will try out your suggestions.

Best wishes

Stephen

[greenxpaddy]

I have another idea...

I don't want to worry you but possibly something in your immediate area is contaminating your water supply which is acidifying it.

A step on from Eric - I would mash with all bottled water as a trial and see what reading you get then. If you get a normal result it is definitely your water. I don't think ph 6.0 water is an acceptable supply level for drinking, so if it is your supply you might have to fight the water company to investigate more. UK regulations state 6.5 is the lowest it is allowed to be.

[BlackRocksBrewery]

Hi - really surprised that no one else has contributed to this. My history is that I used to use pH papers and eventually stopped using them a few years ago because I always obtained mash of around 5.2pH. Then when I had some variation in brews I reverted to using the papers. My readings were then very low ie under 5 in the mash. I have now purchased a Hanna HI 98128 pH meter and I find that the pH of my mash is between 5.2 and 5.3.
I am still concerned as to why my pH papers did not work. Can anyone help?

Now drinking a 4% mild using fuggles hops and 5.2% pale ale using Nelson Sauvin hops
Fermenting - Burton style pale using Liberty and Progress.
and Pale ale using Citra and Cascade.
Each of the last two have been brewed in two 5gall batches. The only difference being that one was brewed using Fawcetts Maris Otter pale malt. The parallel brew used Dingemans malt. Both from the malt miller . It is too early to say which I prefer but both extracts were similar. When looking at the mash I felt that the Dingemans malt was much darker but now in secondary fermentation I find it hard to distinguish between the two. I look forward to tasting the two beers using two different malts.

[mabrungard]

Paper strips have proven quite unreliable for a number of reasons. The ability to decipher color change when dealing with a colored wort, the short life span of paper strips, and the typical pH offset make them unsuitable for brewing use. The plastic ColorpHast strips have proven to be more reliable and consistent, however the pH offset remains. Review the information http://www.homebrewersassociation.org/f ... #msg174260 here. The bottom line is: don't use paper pH strips EVER for brewing, you can get away with the plastic strips, and a calibrated pH meter is still the best indicator of mash pH.

[orlando]

Your link returned no data Martin.

I started out with plastic pH strips and at first they "appeared" to give accurate readings but I stopped relying on them and got a decent pH meter. I too was really surprised at how low your domestic supply pH was. greenxpaddy says there is a statutory requirement for pH, which I was unaware of, but had read it was typically around 7 that most water companies aim for. You have the opposite problem to me where high levels of carbonate make Pale Ales a bit of a challenge. You might take a look at Martin Brungard's website for a very good breakdown of the mysteries of water and water treatment here

[mabrungard]

Orlando, I don't understand why the link doesn't work for you. I just clicked it and it worked for me.

Yes, a pH meter is better than 'good' strips like I mention above. However, many people find the hassle of dealing with a meter, more than its worth. I typically hear good things from brewers that use those plastic strips and know to add 0.3 pH units to the strip reading to give a reasonably accurate pH measurement. For those that make an investment in a good meter and calibrate it before each brewing session, they will have higher confidence in the measurements.

[orlando]

Orlando, I don't understand why the link doesn't work for you. I just clicked it and it worked for me.

Clicked on it this morning and it worked. Reported that it "returned no data" yesterday, so a little mysterious but now OK.

[KaiTroester]

Hi Guys,

A few years back we did an experiment where a bunch of home brewers sent me samples of their ColorpHast strips and I tested them in mash and beer. That's how we established that there appears to be a -0.3 systematic error with the particular strips tested. I'm not sure if these are the same strips you are talking about. While I do have a pH meter I like having the strips around as a back-up.

I never noticed a difference in color based on the immersion time and I did immerse them for different length of time when I noticed that they were off. The correspondence with EMD, that Martin refers to, reflects SOP which is meant to cover lots of different conditions including weakly buffered solutions where it may take longer for the reaction to reach an equilibrium.

Here is a write up of the experiment : http://braukaiser.com/wiki/index.php?ti ... me_brewing

Cheers,
Kai