How to measure the pH of food items using the Horiba PH22 pH Meter
|The pH of food is a measure of how acidic or alkaline the food is. The pH of a food sample can have serious ramifications for food safety as foods with a pH above 4.6-5.2 have a much higher risk of microbial growth.
As such, pH measurements can be used to determine type of processing required to ensure that the food will be safe to consume."
For salami, it is generally recommended to get the Salami down to a pH of approximately 5.2 at which point (along with drying) the salami should be stable and safe.
To quickly check the pH of salami with the PH22 you can cut a small slice of salami and put it onto the sensor. In most cases this will give a suitable reading. If not, it may be necessary to add a bit of distilled water, to help the pH meter take a reading.
If you are looking to take a measurement as per ANZFS Code then you can mince a representative sample of the sausage in a stoppered bottle with twice its weight of water and then shake. A small sample of the liquid can then be placed onto the flat electrode of the PH22 and a measurement can be taken.
Measuring sushi rice
For sushi, the rice used must have a pH of less than 4.6. Below this pH, a majority of the pathogenic and toxin producing bacteria do not multiply rapidly which greatly improves safely.
Vinegar is used to decrease the pH of the rice to a suitable level and often there is enough moisture present that a sample of rice can be placed on the flat sensors of the PH22. If the pH is too high, extra vinegar can be added to the rice until a suitable level is reached.
Measuring liquids and semi-solids like sauce and yoghurt
For liquids and semi-solids like sauces and yoghurts, taking a measurement with the PH22 is easy. Simply place a small sample on the flat sensor and take a reading.
Like sushi rice, you should aim for a pH of 4.6 or lower to minimise the risk of Clostridium botulinum growth.