In the last several weeks, our microbiology lab has had several inquiries regarding indicator testing, so we thought this would be a good opportunity to share some info with you! The two main functions of indicator testing are to verify sanitation measures are working correctly, and to assess spoilage/shelf-life of product. Routine monitoring of organism levels allows you to see what is “normal” for your facility, so that when spikes occur you can troubleshoot whether it was an issue with sanitation, water quality, or some other factor. Indicators are also used to get a feel for the shelf life of a product – higher organism densities may lead to reduced shelf-life and earlier spoilage!
The most common indicators used are E. coli
/ Total Coliforms, Yeast/Mold (for spoilage), and Total Plate Count or TPC (it is worth noting TPC is referred to by a number of different names, including Aerobic Plate Count (APC), Heterotrophic Plate Count (HPC), Total Viable Count (TVC) or Total Mesophilic Count (TMC)). Lately there has also been an increased interest in use of Enterobacteriaceae
as an indicator. Read On »