With pollution index bacteria
We grasp pollution status of microorganism such as food and kitchen utensil, finger and are inspected to evaluate propriety of hygiene management objectively.
Pollution index bacteria have "Escherichia coli" "coliform bacterium" "general standard plate count".
We can suppose having degree and disease-causing germs or not of pollution by checking these bacteria.
General standard plate count
Colony of standard agar
We say bacterial number that cultures at 35 degrees Celsius, and is detected in existing aerobic (needs oxygen) state in food.
The number of this general standard plate count reflects bacteria pollution status of the environmental whole that food and they were produced, and, also, it is extremely influential index because most of pathogen of infectious disease to have through food well grow at around 35 degrees Celsius when we evaluate safety of food, preservation characteristics, propriety of the hygienic handling generally.
General standard plate count does not show safety directly, but shows existence of disease-causing germs, thing that, moreover, those bacteria may multiply when there is much general standard plate count.
Using standard agar, we count all the colonies which grew and calculate general standard plate count per 1 g of food.
Coliform bacterium of desokishikoreito agar
We are arrested for index of feces pollution with drinking water, but are considered to be index of heating in the food mainly.
- Food which ingredient standard of coliform bacterium is set
- Milk, dairy product, cooling drinks, ice and snow
- Heating meat product (we heat up after the packing), fish meat fish paste
- No heating intake frozen foods
- It is intake frozen foods after the heating heated just before freeze
- Frozen yudedako, whale meat product
- Method (sherbet) using desokishikoreito agar
After incubations, when we recognize dark red colony, it is said that estimated examination is positive and carries out decision examination, examination complete in lactose bouillon and gram stain in EMB nutrient medium.
- BGLB nutrient medium, method (cooling drinks, fish meat fish paste) using LB media
When we add sample liquid to nutrient medium which we put fermentation tube in and culture and produce gas, we carry out decision test, perfection examination.
Escherichia coli (E.coli)
When we mean that there was feces pollution relatively new directly or indirectly because probability that there is to feces of Homo sapiens and animal in comparison with coliform bacterium is high and these are easy to perish in the natural world and are detected, it may be said that it is very likely to be pollution of intestinal tract system disease-causing germs.
It is applied to non-heating food such as fresh vegetables, uncooked meat, fishery products that pollution from the natural world is just reflected.
- Food which ingredient standard of Escherichia coli is set
- Oyster of meat product partly for eating raw
- It is intake frozen foods after the heating of non-heating just before freeze
But Escherichia coli fixed for these standards is feces-based coliform bacterium exactly.
Using EC nutrient medium, it is determined by production of gas. In the case of gas production, we may carry out decision test, complete examination.
Other pollution index bacteria
Other pollution index bacteria include "enterococcus, psychrophilic bacteria, high temperature bacteria, spore bearing bacterium".