Validation of the KangarooSci® Aerobic Count Plate for the Enumeration of Meosphilic Aerobic Bacteria in Selected Foods and on Stainless Steel Environmental Surfaces: AOAC Performance Tested MethodSM 062301.

Background: The KangarooSci® Aerobic Count Plate (ACP) is a sample-ready culture medium system for direct counting of aerobic bacteria colonies after 48-72 h of incubation.

Objective: The KangarooSci ACP was evaluated for AOAC Performance Tested MethodsSM certification.

Methods: The KangarooSci ACP was evaluated through matrix studies and product consistency/stability study and robustness testing. For the matrix study, nine food products (nonfat dry milk powder, fresh raw bovine milk, pasteurized liquid bovine milk, fresh raw ground beef, frozen uncooked chicken breast, cooked shredded pork, apple juice, ice cream, and fresh strawberries), and one environmental surface (stainless steel) were evaluated following the KangarooSci ACP product instructions and compared to the ISO 4833-1:2013, Microbiology of food and animal feeding stuffs-Horizontal methods for the enumeration of microorganisms-Part 1: Colony count at 30 °C by the pour plate technique reference standard. The product consistency and stability testing evaluated three separate production lots of the KangarooSci ACP. The robustness testing examined three test parameters, volume of sample plated, incubation time, and incubation temperature, using a factorial study design.

Results: Results from the matrix study demonstrated equivalent performance between the KangarooSci ACP and the ISO 4833-1:2013 reference standard. The product consistency and stability testing showed that the performance of the assay was equivalent over time up to 12 months and between production lots. Minor changes to the operational test conditions showed no significant impact on performance during the robustness testing.

Conclusion: The KangarooSci ACP is an effective method for aerobic plate count for all matrixes evaluated.

Highlights: The KangarooSci ACP allows for fast, reliable enumeration of aerobic bacteria. Utilizing the alternative method takes up less space in incubators, requires no sample spreader, and requires fewer consumables compared to the reference method.