GB 4789.3-2010 National food safety standard Food microbiological examination: Enumeration of coliforms (Text of Document is in English)

01/06/2010

10P

$30.00 USD

National Foods Safety Standard
Food microbiological examination: Enumeration of coliforms
———————————————————————————————————
1. Scope
This standard provides the method for enumeration of coliforms in foods
This standard is applicable to enumeration of coliforms in various foods.
2. Terms and Definitions
The following terms and definitions are applicable to this standard.
2.1 Coliforms
A cluster of concurrently aerobic and anaerobic gram negative sporeless bacilli
which can ferment lactose and generate acid and gas if cultured in 36
for 24 hours.
2.2 Most probable number; MPN
A Poisson distribution-based indirect counting method
3. Devices and Materials
Devices and materials except conventional sterilizing and culturing devices for
microbiological laboratory are as follows:
3.1 Thermostatic incubator: 36±1
3.2 Refrigerator: 2~5
3.3 Thermostatic water bath: 46±1
3.4 Balance: sensitive to 0.1g
3.5 Homogenizer
3.6 Oscillator
3.7 Aseptic suction tube: 1ml (with 0.01ml graduation), 10ml (with 0.1ml graduation)
or micro pipettor and sucker
3.8 Aseptic conical flask: 500ml in volume
3.9 Aseptic culture dish: 90mm in diameter
3.10 pH meter or pH colorimetric tube or precision pH test paper
3.11Colony counter