PH Strips

[Dave S]

It's also worth remembering that the pH scale is logarithmic so a small misjudgement on the colour reading coupled with the relative inaccuracy of pH strips means that the pH reading you decide upon being the measured pH of your mash could be miles out from what it actually is.

Good point Matt, moreover calibrating and measuring the wort at the same temp is a good idea too. I have seen quite a variation in the readings if I'm a little lax. I have calibrated my pH meter to room temperature and allow the mash to cool to that before measuring too. These things are not particularly robust so you really have to look after them. If you do you might get away with replacing the probe once a year . One of the reasons I'm so keen on the Brun' water calculator is that if I can see that it is largely accurate in predicting the pH I may not have to use the meter so much.

I'm finding with today's brew, (a nice malty porter) and the previous one that the measured pH is a tad lower than Martin's calculations. This one I got 5.41-2. MB's calculation 5.52. The previous one was 5.37 instead of 5.48. So both brews have been about 0.11 lower. I'm thinking of using a little less acid next time to see if makes the difference. It could also be that his calculations for the grain content are different from the grains I am using. Either way I doubt it's anything to lose sleep over.

By the way, Orlando, is there any particular reason why you do your water treatment the day before? I always do mine at the start of the session, especially now that I'm treating mash and sparge waters separately.

[Matt12398]

If it's of any interest to you guys I upgraded to the supporter's version of Bru'n Water. It's not a lot different but there are a few improvements and I believe I will now receive any updates.

[Dave S]

If it's of any interest to you guys I upgraded to the supporter's version of Bru'n Water. It's not a lot different but there are a few improvements and I believe I will now receive any updates.

Yes, Orlando, (I think) and I have the supporters version. My main reason was because it supports the use of CRS. But almost immediately I stopped using CRS in favour of phosphoric acid . However, it's such a good piece of software I have no regrets in having made a contribution.

[orlando]

It's also worth remembering that the pH scale is logarithmic so a small misjudgement on the colour reading coupled with the relative inaccuracy of pH strips means that the pH reading you decide upon being the measured pH of your mash could be miles out from what it actually is.

Good point Matt, moreover calibrating and measuring the wort at the same temp is a good idea too. I have seen quite a variation in the readings if I'm a little lax. I have calibrated my pH meter to room temperature and allow the mash to cool to that before measuring too. These things are not particularly robust so you really have to look after them. If you do you might get away with replacing the probe once a year . One of the reasons I'm so keen on the Brun' water calculator is that if I can see that it is largely accurate in predicting the pH I may not have to use the meter so much.

I'm finding with today's brew, (a nice malty porter) and the previous one that the measured pH is a tad lower than Martin's calculations. This one I got 5.41-2. MB's calculation 5.52. The previous one was 5.37 instead of 5.48. So both brews have been about 0.11 lower. I'm thinking of using a little less acid next time to see if makes the difference. It could also be that his calculations for the grain content are different from the grains I am using. Either way I doubt it's anything to lose sleep over.

By the way, Orlando, is there any particular reason why you do your water treatment the day before? I always do mine at the start of the session, especially now that I'm treating mash and sparge waters separately.

Yes, I have had slightly lower than predicted mash pH (brewing today so another opportunity to test it) and you may be right about grain but when I mentioned a slightly lower pH than predicted Martin gave the impression that the level of precision was not to be expected to match every single time. You have to bear in mind that your base water profile is unlikely to be identical all the time, grains might well have an effect too and he has built in some conversions, from SRM to EBC for example that may also have some bearing on it . I may decide to do the same thing as you if my experience continues in the same direction as yours. I think we both need to report the findings to him as well to get his input.

As to why I do it the day before. I like to get the mash on early so I prepare everything the day before for a quick start (Hlt is already on and being held at 80c by my STC 1000). Another reason is I use a campden tablet for reducing the horrendous levels of chlorine in our water and that needs time to do its job so overnight gives it that. The grains are all weighed too and the yeast and my pH fluids are sitting in the brew fridge at "room temperature" circa 20c. The pH fluids for calibrating the meter and the yeast so it is ready to be pitched into the cooled wort. Just checked on the yeast this this morning and it was in my 2 litre flask sitting on the stir plate in the brew fridge, unfortunately I think a problem has occurred with the stir plate as the yeast had dropped out and although I could hear some whirring the stir bar was not spinning; something else to sort out later today .

I do have the supporters version, Barneey has too, and there are a few tweaks that you get with it, such as CRS you mentioned, but things like that are not of interest to me. However I did point out to Martin that his SRM rating of colour was not the European way and could he add the EBC rating to it and he did, so by making a donation it will help to keep him interested in continuing to develop a really good tool.

I have noticed a difference in approach to the "ideal" ranges for certain salts and their ratios compared to say Murphy & Son and their take on water treatment, so it still remains an area of divided opinion. Murphy & Son have a much more relaxed view towards the parameters than Martin's calculator so it makes it very interesting to see what these differences we are finding will actually mean in practice. I wonder whether this is a division cause by "tradition", M&S are predominantly involved in advising British breweries about British beers whereas in the States there is a much greater interest in "style", possibly driving a more obsessive level of scrutiny.

[Dave S]

Yes, I have had slightly lower than predicted mash pH (brewing today so another opportunity to test it) and you may be right about grain but when I mentioned a slightly lower pH than predicted Martin gave the impression that the level of precision was not to be expected to match every single time. You have to bear in mind that your base water profile is unlikely to be identical all the time, grains might well have an effect too and he has built in some conversions, from SRM to EBC for example that may also have some bearing on it . I may decide to do the same thing as you if my experience continues in the same direction as yours. I think we both need to report the findings to him as well to get his input.

As to why I do it the day before. I like to get the mash on early so I prepare everything the day before for a quick start (Hlt is already on and being held at 80c by my STC 1000). Another reason is I use a campden tablet for reducing the horrendous levels of chlorine in our water and that needs time to do its job so overnight gives it that. The grains are all weighed too and the yeast and my pH fluids are sitting in the brew fridge at "room temperature" circa 20c. The pH fluids for calibrating the meter and the yeast so it is ready to be pitched into the cooled wort. Just checked on the yeast this this morning and it was in my 2 litre flask sitting on the stir plate in the brew fridge, unfortunately I think a problem has occurred with the stir plate as the yeast had dropped out and although I could hear some whirring the stir bar was not spinning; something else to sort out later today .

I do have the supporters version, Barneey has too, and there are a few tweaks that you get with it, such as CRS you mentioned, but things like that are not of interest to me. However I did point out to Martin that his SRM rating of colour was not the European way and could he add the EBC rating to it and he did, so by making a donation it will help to keep him interested in continuing to develop a really good tool.

I have noticed a difference in approach to the "ideal" ranges for certain salts and their ratios compared to say Murphy & Son and their take on water treatment, so it still remains an area of divided opinion. Murphy & Son have a much more relaxed view towards the parameters than Martin's calculator so it makes it very interesting to see what these differences we are finding will actually mean in practice. I wonder whether this is a division cause by "tradition", M&S are predominantly involved in advising British breweries about British beers whereas in the States there is a much greater interest in "style", possibly driving a more obsessive level of scrutiny.

By 'eck, you are organised. Mind you, having a dedicated brewing area in the house helps. I have no such luxury.

Yes there are a number of variables in there to make it unrealistic to expect pin-point precision every time. Interestingly these last two brews were widely different in style. The first was a high-ish gravity IPA and yesterday's was a porter. The porter required no mineral additions at all, just 0.5 ml acid in the mash and 4.7 ml in the sparge. So I think I'll do a couple more brews using the calculated amounts of acid and if the error remains about the same I'll try reducing it a bit.

I've not tried M&S's calculator, but I have used BruPak's and of course Graham's and neither have given as good a result as Martin's. As you say, it's important to feed back any adverse findings to him.

[orlando]

Hi Dave, thought I would report back with the pH results. Recalibrated the meter, which was necessary as it was quite a bit out. Then measured in wort at 20 c after recalibrating at 20c so am fairly sure that if the meter is accurate the result is a good test. Predicted mash pH was 5.3 and I got 5.39. As I was looking to have it in the lighter coloured range of 5.3 to 5.4 it is good enough, and of course after all,the calculator says it is an estimate.

[Matt12398]

The M&S suggestions I have are a bit of a one size fits all. The target profiles cover anything from IPAs to bitters and brown ales all under one umbrella with high sulphate levels. Maybe that's right but I wouldn't have had them all the same.

[Eric]

EQUIPMENT.


PROCEDURE.
2 (ancient) pH strips were each cut lengthwise in two and marked for identification.
3 tumblers of 250ml capacity were marked for identification.
250ml of tap water of alkalinity equivalent to 240mg/l CaCO3 was placed in a glass vessel, dosed with 0.4ml CRS and left overnight to mix. Next morning a 5ml sample of this water was tested and found to be acidic. 5ml of tap water was added, mixed and retested. This procedure was repeated until it was found to be neutral when a further 15ml of tap water was added and tested to confirm residual alkalinity of the order of 15mg/l CaCO3.
125ml of this treated water was added to tumbler I. 62.5ml of treated water and the same quantity of untreated tap water were added to tumbler II. Tumbler III had 125ml of tap water added. Small quantities of a calcium salt was added to samples II and III to balance them with the salt (as opposed to carbonate) content of sample I.
All three tumblers were placed in a large pan containing a few cms of water which was then placed on a lighted gas hob until the waters were heated to a bit above 80C.
The pan with tumblers was removed from the gas and when the waters dropped to 73.5C, 50g of lager malt was added to each tumbler and well mixed by hand.

The mash temperature was measured.


Identified pH strips were placed in each mixture and left, the fourth srip was placed in untreated tap water.

The strips were left in the mash for five minutes.

The strips were then removed and surplus liquid shaken from them before they were placed on a white background for comparison.


RESULTS.




CONCLUSIONS.
1 I need to improve the colour replication of my photography.
2. I'll continue using my very old pH strips.

[orlando]

The problem with conclusion number 1 is it doesn't reinforce why you reached conclusion 2, so I suppose we have to accept that you are happy with what you saw. Is that right?

Shame you couldn't have also used a "quality" bench pH meter too, as it would have been interesting to compare how good, or not, the strips are.

The first picture in your results does appear to be the best of them, the others look well out but are dependent not on just your camera but my monitor.

[Eric]

The problem with conclusion number 1 is it doesn't reinforce why you reached conclusion 2, so I suppose we have to accept that you are happy with what you saw. Is that right?

Shame you couldn't have also used a "quality" bench pH meter too, as it would have been interesting to compare how good, or not, the strips are.

The first picture in your results does appear to be the best of them, the others look well out but are dependent not on just your camera but my monitor.

Hi Orlando,
The colour comparison should be made while the strip is still wet and my interpretations for strips I to IIII were 5.3, 5.6, 6.0 and offscale beyond 7. By the time the photos were taken the lustre was fading fast and in intermittent sun I failed completely to get the lighting right. If I were ever to repeat that experiment for publication I would first get the photography sorted.
Yes, it was a pity that I couldn't do a comparison with a decent pH meter, but it confirmed my brewing objectives are not disadvantaged by not having one. Having said that, for some time I've been thinking of conducting tests like of those Sorensen must have and would mean the building of a crude version of what we call a pH meter.