T/HIFSA 0002-2023 Water quality microbiological testing, optical detection method

Scope

Scope: This document specifies the basic principles and requirements for the detection of total coliforms, Escherichia coli, Pseudomonas aeruginosa, and other microorganisms in the water quality of packaged drinking water, including source water, domestic drinking water, and mineral water. This document applies to the qualitative and quantitative determination of total coliforms, Escherichia coli, Pseudomonas aeruginosa, and copper green pseudomonas in water quality. Main technical content: 5. Test methods for total coliforms 5.1.1 Principle: After incubation at 37°C for 24 hours, the microorganisms in the water sample produce changes in pH through metabolism, which cause a color change in the pH indicator of the total coliforms detection reagent. This color change can be observed visually or captured by the signal source of the photoelectric detection device, thereby completing the determination. 5.1.2 Instruments and equipment - Refrigerator: 2°C–5°C. - Vortex shaker. - Sterile pipettes: 1 mL (with 0.01 mL graduations), 5 mL (with 0.1 mL graduations), or micropipettes and pipette tips. - Constant temperature incubator: 36°C ± 1°C. - Microbial photoelectric detection system (e.g., FORBID-M photoelectric detector). - Photoelectric detection tubes (e.g., FORBID-M photoelectric detection tubes). 5.1.3 Culture media and reagents - Total coliforms rapid detection reagent: See Appendix 2.1. - Total coliforms quality control strains: Escherichia coli CICC 10389, Staphylococcus aureus ATCC 25923, and Pseudomonas aeruginosa ATCC 9027. 5.1.4 Test procedures - The total coliforms testing procedure is shown in Figure 1. Figure 1: Total coliforms testing procedure 5.1.5 Operational steps - Prepare the culture medium: Use disposable sterile pipettes or micropipettes and pipette tips to add 5 mL of total coliforms rapid detection reagent per tube. - Inoculate the sample: Use disposable sterile pipettes to withdraw 1 mL of mixed sample and i

Development Information

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