Development of an Alternative to Preservation Efficacy Tests Using the Metabolic Activity of Microorganisms

Consumer products such as detergents, fabric softeners, and cosmetics are typically used in various environments. Manufacturers must ensure the quality of products and ensure their safety through their lifecycle, from manufacturing to usage. Preservation efficacy testing (PET) is typically conducted to determine the preservative of a product prior to use. However, PET is time-consuming and laborious due to its long-term storage and culture-based detection methods. In this study, we focused on the metabolic activities of microorganisms and developed a rapid alternative to PET. We observed that 72 h of preservation was sufficient to predict preservation efficacy using the metabolic activity method. Finally, the accuracy of the metabolic activity method was compared to that of PET using a variety of products such as detergents and cosmetics. The accuracy of this alternative method exceeds 85% for highly fluid and easy-to-handle samples. These results suggest that the developed metabolic activity method possesses the potential to determine the preservative efficacy of products in only four days（72 h of preservation and 24 h of detection）. Thus, this method possesses the potential to provide a rapid and simple alternative to PET.