GB 4789.3-2016 Translated English of Chinese Standard. GB4789.3-2016: National food safety standard - Food microbiological examination - Enumeration of coliforms [Buy--download True-PDF in 3-second: https://play.google.com/books > Sign in > This BOOK > "3-dots" > Export > Save as "*.pdf"]https://www.chinesestandard.net, 11 févr. 2017 - 15 pages This Standard specifies the method for the enumeration of coliforms in food. The first method of this Standard applies to the enumeration of coliforms in food having a low content of coliforms; the second method applies to the enumeration of coliforms in food having a high content of coliforms. |
Table des matières
| 3 | |
Scope | 4 |
Apparatus and materials | 5 |
The first method The MPN count method for coliforms | 6 |
Operating procedure | 7 |
The second method The plate count method for coliforms | 8 |
Operating procedure | 9 |
Annex A Culture media and reagents | 11 |
Annex B Coliform most probable number MPN key | 14 |
Expressions et termes fréquents
1:10 sample homogenate adjust the pH autoclaved sterilization BGLB broth tubes bile agar VRBA Brilliant green lactose buffer or normal Carry out autoclaved chloride 5.0 g Coliform most probable coliforms in food confidence limit containing 225 mL Culture media diluent sample homogenates dilution degree distilled water enumeration of coliforms escherichia coli positive g Sodium gas is produced green lactose bile incubate at 36°C inoculate Lactose 10.0 g lactose bile BGLB Lauryl sulfate tryptose Liquid sample LST broth method for coliforms micropipette mL of distilled mL of phosphate Monopotassium phosphate normal saline Number of positive oxgall pH value phosphate 2.75 g phosphate buffer plate colony count plate count method positive tubes Preparation Dissolve probable number MPN producing gas red bile agar second method secondary fermentation test sterilization at 121°C sulfate tryptose LST suspicious colonies Test procedure test tube typical and suspicious typical colonies Violet red bile VRBA plates water to dilute