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| [ | Date | | | 2024-10-31 15:28 -0400 | ] |
| [ | Current movie | | | Basic Instinct | ] |
A recent newspaper article1 mentioned that flavored sparkling water was often acidic, which I had not realized before. Wanting to confirm the finding, I ordered the most precise set of pH test strips I could find within the “super-cheap” range.
Limitations: I noticed after receiving the test strip that they were only meant to test urine and saliva. I don’t know whether it means that I should expect measured values for other fluids to be completely off.
Notes:
The pH strips I used have two color-changing pads each. Instructions say to match each pad with its own color scale, as printed on the resealable bag, and to average the two readings. The scales both go from 4.5 to 9.0, in increments of 0.25 from 5.5 to 7.5, and in increments of 0.50 for the rest of the range.
Liquids are grouped by typed, and then sorted alphabetically within a group.
| Liquid | top pH | bottom pH | pH (avg) |
|---|---|---|---|
| Coffee, americano | 5.0 | 6.25 | 5.6 |
| Coffee, espresso, Peruvian | 5.75 | 5.0 | 5.3 |
| Coke Zero with Oreo | 5.5 | 4.5 | 5.0 |
| Cola | 5.5 | 5.75 | 5.6 |
| Tea, green, Chinese | 5.5 | 6.5 | 6.0 |
| Vinegar, white2 | 4.5 | 4.5 | ≤4.5 |
| Water, bottled (Eska, label pH: 7.4) | 6.5 | 6.75 | 6.6 |
| Water, sparkling (Bubly, orange) | 6.0 | 5.5 | 5.7 |
| Water, tap | 6.5 | 6.75 | 6.6 |
Keeping in mind the limitations on how much precision can be expected from a very inexpensive testing kit not meant for arbitrary liquid, we can see that:
plain water registers as nearly neutral;
sparkling, flavored water registers as more acidic than plain water, but less acidic than coffee.
The vinegar data point serves to show that this liquid that is known to be acidic is indeed detected as such by the test strips.
The newspaper article, using a laboratory-grade pH-meter in controlled conditions, measured all sparkling water brands at pH values between 3.7 and 5.4. I would assume my numbers are off; and only conclusions about relative acidity of liquids tested with the same set of strips may be valid. Random online sources estimate coffee pH to be very close to 5.0.
La Presse, 2024-09-20, Carburer à l’eau pétillante, est-ce nocif pour les dents ?↩︎
White vinegar is likely more acidic than these test strips can measure; unvalidated online sources say 2.5.↩︎
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David Haguenauer
<www@kurokatta.org>
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