pH of canned foods
Measuring the pH of canned foods can pose challenges. Conventional sensors with spherical sensing membranes are not engineered for use with solid or semi-solid samples, and may not be able to pierce through them. Forced attempts to insert a sensor may in fact give rise not only to inaccurate readings, but scratches on the sensing membrane that cause permanent damage and, hence, decrease sensor lifetime. To counteract this effect, samples can be blended into paste, yet this can be time consuming. Specialized sensors are therefore a more effective means to measure the pH of canned foods.
METTLER TOLEDO's InLab® Solids Pro-ISM is a specialized sensor that can easily measure the pH of canned foods and provide reliable and consistent results. The sensor is designed with a spear shaped tip made of toughened glass that allows direct insertion into solid or semi-solid food samples and is resistant to breakage. This specialized design enables direct measurements of any sample of canned foods, including solid food and liquid brine. This is critical in ensuring reliability and consistency in the manufacturing and quality control processes of canned food samples.
For more information on the advantages of using METTLER TOLEDO's sensors for measuring the pH of canned foods, download our application note.
The following section covers questions and additional information on the importance of measuring the pH of canned foods.
How can I prevent sensor damage while measuring the pH of canned foods?
Check out our video to learn more.
What is in a can of food?
A tin of food contains solid or semi-solid food mixed with brine of a known acid concentration. Normally, canned foods fall under two categories, acid foods and low acid foods. Acid foods have a natural pH of 4.6 or below, whereas low acid foods other than alcoholic beverages have an equilibrium pH greater than 4.6 and a water activity greater than 0.85.
Why are strict regulatory guidelines needed for canned foods?
To protect against serious health risks such as those caused by the pathogen Clostridium botulinum, and to tackle other food safety concerns. 21 CFR (United States Code of Federal Regulations) describes guidelines for the canned foods industry.
Why is measuring the pH of canned foods important?
The pH of canned foods must be monitored and frequently tested during intermittent stages of the production process for compliance. As per the processes mentioned in 21 CFR 114.80, the required pH must be achieved within a designated time. Leakage or underprocessing of canned food causes growth of microbes, leading to spoilage. Measuring the pH of canned foods therefore helps to screen for the presence of certain microbes, as listed in the examination of canned foods chapter in the Food and Drug Administration's Bacteriological Analytical Manual (BAM).
For further details on sensor selection, good measuring practices and procedures, download our application note.