Catalase Activity for Rapid Assessment of High Level Total Mesophilic Microbial Load in Milk

• Published in: Journal of food science Vol. 67; no. 5; pp. 1844 - 1846
• Main Authors: Kang, D.H, Dougherty, R.H, Clark, S, Costello, M
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.06.2002; Institute of Food Technologists; Wiley Subscription Services, Inc
• Subjects: Bacteria; Biological and medical sciences; catalase; Food industries; Food microbiology; Food science; Fundamental and applied biological sciences. Psychology; Keywords: catalase; microbial load; Milk; Milk and cheese industries. Ice creams; milk quality; rapid assessment; rapid methods; Microbiological testing; Enzyme; Dairy product; Rapid technique; Peroxidases; Enzymatic activity; Catalase; Quality control; Mesophily; Control method; Oxidoreductases; Biological contamination; Quantitative analysis; Milk
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1365-2621.2002.tb08732.x

Total mesophilic microbial load (APC) is an important index for milk quality. It takes 48 h to enumerate APC with conventional plating methods. This report presents a rapid catalase activity test for monitoring APC in milk. Most aerobic microorganisms have strong catalase activities. Catalase activity in milk was monitored with a Pasteur pipette method in 5 min. The correlation between high APC numbers (> 4.0 log CFU/ml) and catalase activities was strongly correlated with r(2)=0.89. Classifying the APC into eight contamination groups was found to be a sound means of utilizing the resultant catalase activities to predict APC.