Total Aerobic Viable Counts

Microbiological Investigation 1.1 Total aerobic viable count... 

Total aerobic viable count Establish in-house requirements... 

Total aerobic viable count per standard test method (provide reference number) using membrane filtration method. Sample 100 ml shall be filtrated and placed on low-nutrient content media, at 20 to 22°C for 5 days and observed for another 2 days. 

Total aerobic viable count pour 1 ml into plate containing 25 ml of tryptone glucose extract agar or TSA half concentration. Incubate at 22°C for 5 days. 

The most important tests for indicators, which give a microbiological feel for the produce, are the Total Aerobic Viable (plate) Counts (TVAC), and a test for the presence of coliforms as indicators of faecal pollution. Other tests for indicators may be necessary for certain products or under certain storage conditions, e.g. psychrophilic plate counts for items stored at low temperature, anaerobic plate counts for suspect tinned items, and tests for enterococci in cases of suspected food poisoning. In certain items of produce, large numbers of indicator organisms may also pose a threat to health in their own right. 

Total Viable1 Anaerobes Total Viable Aerobes Total Bacteria (microscopic counts)... 

Microbial limits Total viable count for aerobic bacteria and yeasts/molds. X X... 

Microbial limit tests, as described in USP 24-NF 19 (<61>) provide the information necessary to conduct bioburden counts by quantitative estimations of viable aerobic microorganisms in pharmaceutical articles, raw materials, and finished dosage forms. Consult the EP or JP for any differences in these methods from those of the USP. Note that USP (<61>) is currently under revision and that the next version will be fully harmonized between the USP, EP, and JP. The microbial limit test comprises the total aerobic bacterial (microbial) count (TAG), the total combined yeasts and molds count (TYMC), and tests for indicator organisms. Bioburden tests are also referred to as total viable counts. This test estimates the total number of viable (culturable) aerobic microorganisms in various items including parenteral UBPS. The total viable count is obtained by adding the counts from the TAC and the TYMC. 

European Pharmacopoeia (Eur. Ph.) (2005), Microbiological examination of nonsterile products (total viable aerobic count), general chapter 2.6.12, Council of Europe, Strasbourg Cedex, France. 

Total viable aerobic count, determined by plate-count. 

In practice microbiological quality of water is monitored by action and alert levels. Thus the user will be early notified about any deviation of critical parameters. For instance an alert level might be put at a factor 10 below an action level. To determine these levels a good set of total viable aerobic counts, endotoxin assay results and TOC assay results should be available. For the collection of these results, particularly in the start-up phase very frequent measurements must be executed. 

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