Understanding the type of microorganisms and the extent of contamination in various environmental areas of a food industry provides the industry a defined framework on the potential problems that could occur due to microbial contamination which will affect the finished products quality. To ensure safety of consumers every food handling environment should define an environmental monitoring program which can help determine if the processing environment is under microbiological control.
Good hygiene, cleaning and disinfection procedures should be in place to ensure that the food processing environment is free from unacceptable levels of microbial contaminants.
TUV India testing laboratories follow internationally approved methods and can help you by checking the effectiveness of your environmental monitoring program by performing environmental hygiene, air sampling, plate monitoring and swab analysis for surfaces and individuals.
The measurement of microbial cleanliness goes beyond what can be seen by the naked eye. There are a number of ways in which the food processing environment can be monitored to ensure that the highest standards of cleanliness are maintained.
Vectors of Contamination:
• Raw materials
• Food Handlers & Equipment handlers
• Processing Equipment
Where to monitor :
An environmental monitoring program should include the regular screening of surfaces, such as worktops, sinks, drains, utensils, equipment, walls, floors and ceilings, air quality within the food processing environment and food handlers.
Ways to monitor
1. Air Sampling Some microbial contaminants may be carried in the air. They can originate from external sources (via doors and windows) or they can be derived from internal sources (i.e., personnel, dust particles or aerosols created during production). Thus, quality of air in the food processing environment should be monitored regularly.
The most commonly used medium for air sampling is by placing plates (petri dishes) in and around processing areas where greatest risk of microbial contamination can occur.
|Active Monitoring||Passive Monitoring|
Air is drawn under pressure onto the collection medium (e.g., Petri Dish with nutrient agar based test media) over a specified period of time. The collected culture can then be incubated and analyzed.
Petri dishes with media are opened and exposed to the air for specified periods of time to determine what microbiological particles may be present in the environment, as they may settle out of the ambient air, and onto the media surface of the petri dish. These plates are then incubated and analyzed.
|Microbial air sampler is used.||Settle Plates with media are used.|
2. Swab collection:
Swab collection is usually done to check the effectiveness of disinfection/cleaning procedures. Swabbing should be performed after the surface has been cleaned and is also used to check personal hygiene of food handlers. Swabbing can be done as part of a routine hygiene inspection without prior cleaning.
A high count can be an early warning of inadequate cleaning practices and personal hygiene in food premises. The method of choice for examination of surfaces is swabbing of a known area (10- 100 cm²) using a sterile swab that has been moistened in 10 ml of neutralizing diluent. This semi-quantitative approach enables enumeration of the micro-organisms per cm² and can facilitate interpretation of the results.
In case there is a large surface area that needs to be monitored, we use sponge-stick swabs which are designed specifically for microbial surface sampling. The sponge stick swabs allows sampling without touching the sponge, increasing efficiency with less risk of contamination.
Microbiological examination of garments/cleaning cloth can also be useful both in monitoring general hygiene and in the investigation of outbreaks as they have the potential to spread microbial contamination over the surfaces.
3. Contact plates:
Contact plates can be used for environmental monitoring of surfaces .Contact plates are the standard devices for environmental monitoring of surfaces and personnel in cleanrooms and isolators.