National Food Safety Standard- Food Microbiological Examination - Enumeration of Faecal Coliforms
1 Scope
This standard specifies the methods for enumeration of faecal coliforms in foods.
This standard is applicable to the enumeration of faecal coliforms in various foods.
2 Terms and Definitions
2.1 Faecal coliforms
It refers to the aerobic and facultative anaerobic gram-negative sporeless bacillus which can ferment lactose with the production of acid and gas after having been cultured at 44.5℃ for 24h~ 48h. This flora comes from the faeces of human and warm-blooded animals and may be used as a fecal pollution indicator to evaluate the hygienic condition of foods and to conclude the possibility of enteropathogenic bacteria pollution in foods.
3 Equipment and Materials Required by the Technology
In addition to the conventional sterilization and cultivation equipment in microbiological laboratory, other necessary equipment and materials are as follows:
a) Constant temperature incubator: 36℃±1℃;
b) Refrigerator: 2℃~5℃;
c) Thermostatic waterbath: 44.5℃±0.2℃;
d) Balance: with sensibility of 0.1g;
e) Homogenizer;
f) Oscillator;
g) Aseptic suction tube: 1mL (with scale division of 0.01mL) and 10mL (with scale division of 0.1mL) or micropipettor and suction head;
h) Aseptic conical flask: with volume of 500mL;
i) Aseptic culture dish: in diameter of 90mm;
j) PH meter or pH colorimetric tube or precise pH paper.
4 Culture Media and Reagents
4.1 Lauryl Sulfate Tryptose (LST) broth: see A.1 in Appendix A.
4.2 E.coli broth: see A.2 in Appendix A.
4.3 Aseptic normal saline: see A.3 in Appendix A.
4.4 1mol/L NaOH: see A.4 in Appendix A.
4.5 1mol/L HCl: see A.5 in Appendix A.
5 Examination Procedures
See Figure 1 for the examination procedures of faecal coliforms.
Foreword I
1 Scope
2 Terms and Definitions
3 Equipment and Materials Required by the Technology
4 Culture Media and Reagents
5 Examination Procedures
6 Operation Steps
Appendix A Culture Media and Reagents
Appendix B Methods for Determining Three Optimal Continuous Dilutions
Appendix C Most Probable Number (MPN) Table of Faecal Coliforms
Standard
GB 4789.39-2013 National Food Safety Standard-Food Microbiological Examination – Counting of fecal coliform (English Version)
Standard No.
GB 4789.39-2013
Status
valid
Language
English
File Format
PDF
Word Count
5000 words
Price(USD)
150.0
Implemented on
2014-6-1
Delivery
via email in 1 business day
Detail of GB 4789.39-2013
Standard No.
GB 4789.39-2013
English Name
National Food Safety Standard-Food Microbiological Examination – Counting of fecal coliform
National Food Safety Standard- Food Microbiological Examination - Enumeration of Faecal Coliforms
1 Scope
This standard specifies the methods for enumeration of faecal coliforms in foods.
This standard is applicable to the enumeration of faecal coliforms in various foods.
2 Terms and Definitions
2.1 Faecal coliforms
It refers to the aerobic and facultative anaerobic gram-negative sporeless bacillus which can ferment lactose with the production of acid and gas after having been cultured at 44.5℃ for 24h~ 48h. This flora comes from the faeces of human and warm-blooded animals and may be used as a fecal pollution indicator to evaluate the hygienic condition of foods and to conclude the possibility of enteropathogenic bacteria pollution in foods.
3 Equipment and Materials Required by the Technology
In addition to the conventional sterilization and cultivation equipment in microbiological laboratory, other necessary equipment and materials are as follows:
a) Constant temperature incubator: 36℃±1℃;
b) Refrigerator: 2℃~5℃;
c) Thermostatic waterbath: 44.5℃±0.2℃;
d) Balance: with sensibility of 0.1g;
e) Homogenizer;
f) Oscillator;
g) Aseptic suction tube: 1mL (with scale division of 0.01mL) and 10mL (with scale division of 0.1mL) or micropipettor and suction head;
h) Aseptic conical flask: with volume of 500mL;
i) Aseptic culture dish: in diameter of 90mm;
j) PH meter or pH colorimetric tube or precise pH paper.
4 Culture Media and Reagents
4.1 Lauryl Sulfate Tryptose (LST) broth: see A.1 in Appendix A.
4.2 E.coli broth: see A.2 in Appendix A.
4.3 Aseptic normal saline: see A.3 in Appendix A.
4.4 1mol/L NaOH: see A.4 in Appendix A.
4.5 1mol/L HCl: see A.5 in Appendix A.
5 Examination Procedures
See Figure 1 for the examination procedures of faecal coliforms.
Contents of GB 4789.39-2013
Foreword I
1 Scope
2 Terms and Definitions
3 Equipment and Materials Required by the Technology
4 Culture Media and Reagents
5 Examination Procedures
6 Operation Steps
Appendix A Culture Media and Reagents
Appendix B Methods for Determining Three Optimal Continuous Dilutions
Appendix C Most Probable Number (MPN) Table of Faecal Coliforms
