One of the most important forms of analytical — or materials — testing in the food industry occurs when measuring pH levels of certain food products. From the pH levels of cheeses, yoghurt, wines, and even the water used in bread, getting the pH right has as much to do with taste and consistency as it does with food quality and safety.
Testing pH Levels in Food
For this reason, let’s take a look at why pH testing is such an integral step in food production, what pH testing indicates, and why accurate pH testing can so be so hard to get right — unless you choose to work with an experienced food testing laboratory like Log10.
Note that the careful monitoring of pH levels of many food production processes is critical to preventing the growth of harmful microbial organisms and bacteria like botulism. This is why pH testing is often mandated under the U.S. Food and Drug Administration’s regulations for safe food production.
Why pH Testing Is Important
It’s clear that testing pH in food products serves many purposes and is at times a legal requirement. So what actually is pH, and what does testing for it in foods reveal?
The test for potential hydrogen — or pH — is a measurement of the number of hydrogen ions in a specimen or solution. While many people believe that pH testing is simply about testing acidity levels, it’s really about discovering the levels of hydrogen atom nuclei, which are symbolized as H+. Of course, there’s a relationship between isolated hydrogen ions and acid levels, but separate testing procedures such as titration can be performed to specifically measure acidity.
The pH scale ranges from “0,” considered highly acidic — like battery acid — up to “14,” considered highly alkaline or basic — like potassium hydroxide. In the middle, at “7,” is a neutral reading — such as pure water.
How pH Testing Can Indicate Food Safety & Product Quality
Accurately testing foods for pH levels reveals many important factors. For example, in foods that are prepared for canning, a pH level of 4.6 or lower means that harmful pathogens and bacteria won’t be able to grow, which is a major food safety indicator.
Consider some other popular applications of pH testing in food products:
- Yoghurt: The cultured milk used to make yoghurt must have a pH level of 4.6 or less before cooling begins to achieve proper tartness and coloring. If fruit is added, it must also be of the same pH, or the mixture must be properly acidified.
- Wine: To achieve a pleasing aroma, taste, and appearance, most wines measure somewhere between 3.0 and 4.0 on the pH scale. In addition, these pH levels indicate that the growth of microbes is prevented and the wine is resistant to spoiling if bottled properly.
- Cheeses: pH levels of healthy milk usually range from 6.5 to 6.7 — anything higher can indicate illnesses in the cows producing the milk or other forms of contamination. Once the process of making cheese is underway, lower pH levels typically produce smoother, more creamy cheeses, while higher levels produce crumbly, more brittle cheeses.
- Meats: The pH levels of certain meats can indicate their quality. For instance, a healthy pig that’s slaughtered correctly will produce pork with pH levels ranging from 5.6 to 6.0, while an unhealthy pig that’s slaughtered under stress can produce pork with a pH as low as 4.9.
Comprehensive Food Acidity Testing Services
Since the results of pH testing are so vital to the food industry, it’s critical that the professionals carrying out the tests, as well as the equipment they use, are absolutely trustworthy. Everything from the training and professionalism of food testing technicians to the proper storage and calibration of pH testing equipment needs to be of the highest caliber for results to be accurate.
Fortunately, Log10 is an ISO 17025 accredited testing facility with a biological level II (BSL 2) pathogen laboratory. We offer comprehensive food safety analytical testing, including pH testing services, to support all types of food production for both human and animal consumption.