Frequently Asked Questions
Compliance & Regulations
Which microbiological tests are legally required for my product?
It depends on your product type, target market and the available legislation or guidelines (South African Acts and Regulations, ISO or SANS standards, Codex Alimentarius guidelines, or retailer requirements). We can review your product and provide a recommended test list.
Which standards apply to my product?
Standards may be local (e.g. R1555 for milk, SANS 885 for processed ready-to-eat meat products), international (e.g. Codex Alimentarius), or retailer specific. We will match your testing plan to the right standard.
What are the acceptable limits for microorganisms?
Limits are set in regulations, buyer specifications, or guidelines such as Codex. Some organisms (e.g. Salmonella and Listeria monocytogenes) must not be detected in ready-to-eat foods, while other organisms have maximum permissible counts.
Do I need to test every batch?
Not always. Sampling frequency can be determined by risk assessment, product shelf-life and customer requirements.
Will these results meet FSSC 22000 / HACCP / retailer requirements?
Yes — we can test to meet certification and buyer requirements.
Testing & Methodology
Which microbiological tests should I request?
Common tests include:
- TVC / TPC / TBC / TMA – Total viable aerobic bacterial count
- Coliforms / E. coli counts– Hygiene indicators
- Yeasts and moulds / Lactic acid bacteria / Pseudomonas counts – Spoilage risks
- Pathogen counts – Staphylococcus aureus, Bacillus cereus, Clostridium perfringens
- Pathogen detection – Salmonella, Listeria monocytogenes
We can tailor testing to your product and risk profile.
What’s the difference between TVC / TPC / TBC / TMA?
They are different names for similar methods — all measure the total number of viable aerobic bacteria in a sample. Terminology may vary by country and method.
How are swab or sponge samples processed?
The swab is placed into sterile diluent/enrichment broth, mixed, and cultured on selective and/or non-selective media to recover/count microorganisms. Separate swabs need to be submitted for counts and detection tests. Example: You request TVC, coliform and E. coli counts, as well as Salmonella and L. monocytogenes detection. One swab is needed for the counts (TVC, coliforms and E. coli), a second swab is needed for Salmonella detection, and a third swab is needed for the L. monocytogenes detection.
How long will it take to get results?
This depends on the tests being conducted.
Can you test for both pathogens and spoilage organisms in the same sample?
Yes — we can run multiple tests from one sample to save time and cost. The only exception to this is swabs.
What’s the difference between rapid and traditional culture methods?
Traditional methods rely on growth on agar plates; rapid methods use molecular, immunochemical or automated biochemical techniques for faster results (often same-day or next-day).
Sampling & Submission
How should I collect and transport samples?
Use sterile containers or swabs. Store and transport the samples at the appropriate temperature e.g. room temperature, refrigerated or frozen. Deliver the samples to the laboratory as quickly as possible (preferably within 24 hours of collection).
What’s the minimum sample size?
This will depend on the tests requested. For enumeration tests only: Please provide at least 50 g or 50 mL of sample. For detection tests: please provide at least 50 g or 50 mL of sample per test.
How should samples be stored before delivery?
Store the samples at a temperature that is appropriate for the sample type e.g. room temperature, refrigerated or frozen. Swabs, water and air plates should be refrigerated as soon as possible after collection.
Do you provide sampling kits?
Yes — sterile containers, swabs and neutralising medium, air plates, and coolers. We also offer a collection service.
Can you do on-site sampling?
Yes — we can send trained staff members to collect environmental, product, or water samples.
Understanding Results
This result means that no growth was obtained when a 1:10 dilution of the sample was tested. This is a typical “no growth” result for solid samples, where dilution of the sample is necessary to facilitate plating or testing using automated methods.
My results are higher than the limit — what does that mean?
It indicates non-compliance with the relevant specification. Depending on which test is out-of-specification, the result may affect product quality or safety. We can help investigate the cause.
Why are my counts different from last time?
Microbial counts can vary due to raw materials, process changes, seasonal differences, or storage conditions.
What’s the difference between “presence/absence” and enumeration tests?
Presence/absence testing is qualitative and reports results as either “detected” or “not detected”. Enumeration testing is quantitative and reports the actual count obtained. Presence/absence tests are typically used for pathogens such as Salmonella and Listeria, where the anticipated number of organisms present is too low to be accurately counted.
Do you provide interpretation or advice?
Yes — we offer result interpretation, risk assessment, and recommendations. It must however be noted that any interpretations or advice offered are beyond the scope of our accreditation.
Troubleshooting & Root Cause
Why did my product fail microbiological testing?
Possible causes include contaminated ingredients, inadequate heat treatment, poor hygiene, cross-contamination, or storage abuse.
Could contamination have come from ingredients, equipment, or staff?
Yes — root cause investigations often find contamination from raw materials, dirty equipment, water, air, or handling.
What environmental monitoring programme should I have?
We can design a programme that includes swab testing of surfaces, equipment and hands, air plates for monitoring air quality, and water testing.
How do I reduce counts in my production area?
Improve cleaning and sanitation, maintain equipment, monitor hygiene, and control temperature and humidity.
Do you offer training for staff?
Yes — on sampling, hygiene, environmental monitoring, and understanding laboratory results.
Special Testing Requests
Can you test for allergens, toxins, or chemical residues?
Yes — via accredited partner laboratories.
Can you identify unknown bacteria or mould?
Yes — through culture, microscopy, MALDI-ToF and molecular identification.
Do you offer challenge testing or shelf-life studies?
Yes — we offer preservative efficacy testing on cosmetics as well as real-time and accelerated shelf-life testing on a variety of products.
Can you customise tests to my buyer’s specification?
Absolutely — we regularly work to retailer or export market specifications.