Total Yeast and Mold

The Total Yeast and Mold Count (TYMC) test is a microbiological testing method used to estimate the total number of viable yeast and mold present in a given sample. The TYMC test is commonly used to assess the quality and safety of food, beverages, and other substances that can support the growth of yeast and mold.

In the TYMC method, a sample is diluted in a sterile diluent and plated onto a specific agar medium that supports the growth of yeast and mold. After incubation, the number of colony-forming units (CFUs) on the agar plates is counted, and the results are expressed as the number of CFUs per unit volume or weight of the original sample.

The TYMC test is similar to the TAPC method in that both are measures of the microbial load in a sample. However, the TYMC test specifically targets yeast and mold, whereas the TAPC measures the total number of viable aerobic microorganisms, including bacteria, yeast, and mold. Additionally, the agar media used for the TYMC and TAPC tests are different. While the TAPC typically uses Tryptic Soy Agar (TSA), the TYMC method uses specific agar media that support the growth of yeast and mold, such as Sabouraud Dextrose Agar (SDA).

It’s worth noting that while the TYMC test is a useful indicator of the overall microbial quality of a sample, it does not provide information about the specific types of yeast and mold present in the sample. Further testing may be needed to identify and quantify specific yeast and mold species of concern.

Common methods used for Total Yeast and Mold Count are USP <61>, USP <2021> and EP (2.6.12).