pH Confusion

[Hamish]

Hi all, 

I am in Cambridgeshire and have been making cider for a few years with mixed results. 

I have several batches from the 2025 season which are still on the their primary lees. They have been stored in a reliably cool outbuilding. They are all unsulphited. I have been tasting quite regularly in the last couple of months because I think malolactic fermentation has been going on, and the ciders all started tasting really quite unpleasant during this period, (which was alarming!) but now seem to have settled down and taste good again (with a couple of exceptions). Whenever I take a sample I have topped up with the first batch that finished form 2025, which fermented quickly and was pretty sharp, although has mellowed a lot now.

I have recorded what seems like quite dramatic changes in pH  (just using cheap Harris pH papers): for example, at time of pressing the juice of one batch gave pH 3.2 and the resulting cider is now reading pH 4. The cider smells and tastes clean, is very aromatic, pleasant to drink although doesn’t have a lot of oomph in terms of taste. It is quite typical ‘eastern counties’, and made with cookers and eaters. 

I know that yeast fermentation and Malolactic fermentation can alter pH of the cider but is such a big jump likely to have taken place? Other batches have started low, and gone up, but not all into the ‘danger zone’ like this one. Some are have gone from pH 3.2 up to 3.6. 

I am concerned/confused about the following:

Which measurement, the pH of the fermented cider, or the pH of the original juice, is the best guide as to whether the cider is protected from spoilage once in bottle? 

Are the primary lees of these higher pH ciders preventing spoilage, and when I rack and bottle will I be asking for trouble if I don’t add sulphite?  

If I am using pH papers that are a year old am I running the risk of getting inaccurate readings?

If I draw off some cider into a clean and rinsed but not dry vessel, will the water residue alter the pH reading of the cider sample?

Forgive me for long-winded post, and if these questions are a bit daft, I’m just trying to get to grips with making a plan for bottling and don't want to bottle ciders that aren't going to store well.

Thanks in advance for any clarifications/reassurance you might be able to offer!

Cheers, Hamish 

[Thomas Christie]

Hi Hamish 

In terms of spoilage, it’s the final pH which is the relevant measure for bottle stability. However, I think something is off here in your pH measurements. A change from 3.2 to 4.0 from MLF I believe is essentially impossible. 3.2 is also already quite a low pH for malolactic to spontaneously establish itself, so if I had to guess there may have been a measurement error on the juice end. Possibly on both ends I suppose. 

A little water in your sample likely didnt affect the measurement too much. In theory distilled water wouldn’t effect pH at all, and unless your water is very hard and made up a decent proportion of your sample I wouldn’t guess this to be the cause of error.

The lees can act as an oxygen scavenger and thus may offer some slight protection against spoilage from aerobic organisms.

If the pH is truly 4.0 that would worry me a bit in terms of spoilage, but sulfite won’t be the answer because if yields basically zero antimicrobial protection in that pH range. 

I might just buy some new pH strips and test again, the old strips could be the source of the confusion here.

-Tom

--
--
Visit our website: http://www.ciderworkshop.com
 
You received this message because you are subscribed to the "Cider Workshop" Google Group.
By joining the Cider Workshop, you agree to abide by our principles. Please see http://www.ciderworkshop.com/resources_principles.html
---
You received this message because you are subscribed to the Google Groups "Cider Workshop" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cider-worksho...@googlegroups.com.
To view this discussion, visit https://groups.google.com/d/msgid/cider-workshop/CA%2BRXuyTawbuoNuPqaUvvu7QMz0KA4Er7xTVfpB566eN2U4qsEQ%40mail.gmail.com.

[Hamish]

Hi Tom,

thank you very much for your response, it is reassuring to know that the measurements seem off to someone else. I will test again with new papers!

Hamish 

To view this discussion, visit https://groups.google.com/d/msgid/cider-workshop/CAJ7_0Twc1Se79sFxPcrNq2v5etXd3Le4MZHUo%2BoyuKekn3bNzA%40mail.gmail.com.