T-01
Microbiological testing
Testing for the organisms that make people ill, and for the indicator organisms that warn you the process is drifting before they appear.
- What it is
- Pathogen detection and indicator counts
- Who it is for
- Food, feed, water and ready-to-eat manufacturers
- Turnaround
- 5–7 days
WHAT THIS IS
What this is, and why it matters
Microbiological testing looks for living organisms in your product, your water and your production environment. It does two different jobs that are often treated as one. Pathogen detection asks a yes-or-no question about a named organism — Salmonella, Listeria monocytogenes — and the answer usually decides whether a batch is released. Indicator enumeration counts organisms that are not themselves the hazard but rise when hygiene, temperature control or process control slips: aerobic plate count, Enterobacteriaceae, coliforms, yeasts and moulds.
The second job is the one most manufacturers under-use. A pathogen result describes one batch on one day. An indicator count tracked over time describes the direction your process is moving in, which is the only warning you get before a pathogen result arrives. Both run to published international methods here, and the report carries the method reference on the result line so that whoever reads it next — your customer, your auditor, the regulator — can see exactly what was done.
What this lane covers
- Pathogen detection and indicator organism enumeration
- Food, feed, water, surfaces and process environments
TRIGGERS
When you need it
Your food safety scheme requires verification
HACCP, ISO 22000, FSSC 22000 and the retailer standards all require evidence that your controls actually work. Microbiological results are the usual evidence, and an auditor asks for them by sampling point and by date, not as a single certificate in a folder.
A specification names the limit
Retail and food-service buyers set microbiological limits on the products they list, and those limits are contractual. Testing against the specific limit in your contract is the only result that answers the question that was asked.
Something has already gone wrong
A complaint, a positive environmental swab, a temperature excursion or a withdrawal investigation all need results that will hold up months later. Investigation samples are handled exactly like routine ones, so the record is defensible either way.
CATALOGUE
Microbiology — parameters
Aerobic plate count
- Matrix
- Food
- Reference method
- ISO 4833-1
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Enterobacteriaceae
- Matrix
- Food
- Reference method
- ISO 21528-2
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Coliforms
- Matrix
- Food
- Reference method
- ISO 4832
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Escherichia coli
- Matrix
- Food
- Reference method
- ISO 16649-2
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Escherichia coli O157 (detection in 25 g)
- Matrix
- Food
- Reference method
- ISO 16654
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Salmonella spp. (detection in 25 g)
- Matrix
- Food
- Reference method
- ISO 6579-1
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Listeria monocytogenes (detection and enumeration)
- Matrix
- Food
- Reference method
- ISO 11290-1/2
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Staphylococcus aureus
- Matrix
- Food
- Reference method
- ISO 6888-1
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Bacillus cereus
- Matrix
- Food
- Reference method
- ISO 7932
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Clostridium perfringens
- Matrix
- Food
- Reference method
- ISO 15213-2:2023
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Campylobacter jejuni
- Matrix
- Food
- Reference method
- ISO 10272-1
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Pseudomonas aeruginosa
- Matrix
- Food
- Reference method
- ISO 13720
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Yeasts and moulds
- Matrix
- Food
- Reference method
- ISO 21527-2
- Run by
- Nexus bench
- Turnaround
- 5–7 days
Published from the laboratory’s own method list. Reference methods shown are the primary reference for each determination; the full reference set, sample requirement and confirmed turnaround are issued in writing before any sample is accepted.
PROCESS
How it works
Send the brief before the sample
Matrix, the organisms you need, sample count, and the limit you are reading against if there is one.
Sample requirements confirmed in writing
Container, quantity, temperature and hold time change with the organism and the matrix, so they are confirmed to you in writing before dispatch. A sample that arrives warm or late has already given you a wrong answer, and no amount of bench work recovers it.
On the bench, to a published method
Every determination runs to the ISO, AOAC or APHA method named in the catalogue above, and that reference travels onto the report line rather than sitting in a footnote. Turnaround runs from acceptance at the laboratory, not from the day the sample left you.
Reported so the result can be acted on
Where a limit applies, the report states the limit, where that limit came from, and the verdict against it. Where none applies, it reports the count and the method and stops there rather than inventing a verdict you did not ask for.
What you get back
A report carrying sample identity, the method reference per line, the result with its unit, and — where a limit was named — that limit and the verdict against it. Issued per sample, retained by the laboratory, traceable back to the batch you took it from.
Service facts
| Parameter | Value | Note |
|---|---|---|
| Accreditation position | Accredited. Certificate N-T-00607 covers food and agricultural microbiology to ISO/IEC 17025:2017. Determinations outside that field — and pathogen detection generally — run to published methods outside the accredited scope, and each report states which applies. | Stated per discipline, never implied by a badge. |
| Sample requirements | Confirmed to you in writing before dispatch. Container, quantity, temperature and hold time change with the parameter and the matrix, so they are issued per request rather than published as one list. | Per-parameter detail publishes with the confirmed method list. |
Q+A
Common questions
Microbiology
Can you test to my customer’s specification?
Yes. Send the specification and the laboratory confirms in writing which parameters it will test and which limits it will report against. Where the specification is silent on a limit, GSO 1016:2015 microbiological criteria are the usual reference for food.
Is your microbiology testing accredited?
Yes. The laboratory holds SAAC accreditation to ISO/IEC 17025:2017 for food and agricultural microbiology, certificate N-T-00607. The report for your samples states whether each test falls inside that scope.
A pathogen result came back positive — what happens next?
The result is reported as found, with the method stated. Retesting the same sample does not make a positive go away; the useful work is deciding what the batch and the line need, and that decision is yours. The report gives you the result against its criterion, so you are deciding against a limit, not a bare number.
Does it matter how I send the sample?
Yes — counts change with time and temperature, so transport condition is part of the result. The laboratory confirms sampling and transport requirements in writing before you send, and the report records the condition the sample arrived in.
Can you test water and environmental swabs too, or only food?
The microbiology laboratory covers food, feed, water and environmental samples. Water testing and environmental monitoring have their own pages because they are run as programmes, not one-off tests — but the samples land on the same benches.
Send the sample question or the instrument list. It is read by a bench professional, not routed through a ticket queue. Call +966 59 637 8052 or write to lab-mgr@qsinexus.com.
CONTINUE
Where to next
Sending a sample
Packing, labelling, temperature and what has to travel with the sample so it arrives usable.
ReadThe GSO standards that actually bite
GSO 1016:2015 sets the microbiological criteria most results are reported against.
ReadHygiene and sanitation verification
Verification that your cleaning actually works, with a documented result behind every shift release.
Read