Challenge Test Record

This record answers one specific question — does the formulation control a named organism across its full shelf life — and it answers it through a laboratory study, not a desk review. Using it for anything less specific produces a record that looks like evidence but isn't.

BRCGS cl.5.1 expects higher risk products to carry microbiological challenge evidence, not just a shelf life claim. The clause doesn't specify a protocol, which is why the judgement calls below sit with the technical manager rather than the template.

Challenge testing sits at the intersection of a certification standard, a specific EU regulatory driver, and international scientific guidance on method — a study can satisfy one and still fail another.

The fields are simple to fill in. The four calls below are what actually decide whether the finished record would survive scrutiny.

The failure modes below recur across challenge test programmes and each one is visible directly in the fields the template already asks for.

A chilled RTE producer extended a product's shelf life from 14 to 21 days on the strength of a challenge test that showed no growth. The test had been run on a freshly made batch at the recipe's nominal pH and salt level, refrigerated at a steady 4°C throughout — Worst Case Formulation Used was answered "Typical only" and Temperature Abuse Included was marked "No", but neither field was queried before the extension went ahead.

Three months later, a batch that had drifted to the low end of the salt specification, combined with a delivery delay that let temperature rise for several hours, showed growth well past what the study had modelled. The formulation had never actually been proven safe at day 21 under real conditions — only under the one set of conditions that happened to be convenient to test.

Completing the record is the laboratory's job. Making sure the result actually changes the shelf life claim, the HACCP plan and the next study's parameters is the part that depends on someone tracking it across records.

KnowQuality

Holds the challenge test record against the product register and HACCP plan, and flags when a study result implies a shelf life or formulation change that hasn't been actioned yet.

KnowSafe

Keeps the organism-of-concern reasoning and hurdle documentation consistent with the wider food safety plan, rather than isolated inside one study record.

KnowComply

Tracks which studies were run against worst-case conditions and beyond the labelled date, so audit evidence doesn't rely on someone remembering which protocol was used.

Ella

Coordinates the crew across the study, the HACCP update and the shelf life claim, and holds every write for your approval before it touches a record.

Organism of concern

The specific pathogen a challenge test is designed around, chosen for relevance to the product type — for example Listeria monocytogenes in chilled ready-to-eat foods or Clostridium botulinum in reduced-oxygen packaging.

Worst-case formulation

The combination of pH, water activity, salt and preservative levels at the edge of what the process can produce, rather than the recipe as designed — the version most likely to permit growth.

Log growth

The change in organism count expressed on a logarithmic scale; a one log increase means the population grew tenfold. Regulatory growth limits are typically expressed this way rather than as raw counts.

Hurdle technology

The combination of controlling factors — pH, salt, preservative, temperature — that together prevent an organism from growing, even when no single factor would be sufficient alone.

Temperature abuse profile

A deliberately realistic pattern of temperature excursions built into a storage study, reflecting what actually happens during distribution and retail handling rather than a laboratory's steady, ideal fridge.