Every use-by and best-before date is a claim, and the manufacturer carries the burden of proving it. We design the study programme that backs that claim, traceable to your formulation, your process, and your packaging.
Shelf life testing is the process by which a food manufacturer determines and validates how long a product remains safe and acceptable for consumption under specified storage conditions. It is the manufacturer's responsibility to determine shelf life, and the resulting date, use-by for safety-critical products or best-before for quality-related ones, must be traceable by formulation, recipe, or product code to product development records.
This matters because a shelf life date is a claim made on the label, and like any claim, it needs evidence behind it. Inaccurate shelf life dates violate FDA, EU, FSANZ, and other national labelling regulations, risking penalties, but the consequences extend beyond regulatory risk: spoilage or pathogen growth before the stated date risks consumer health and recalls, while an overly conservative date increases food waste and can reduce a product's competitiveness on shelf.
Shelf life depends on the interaction of multiple factors, formulation, process, and packaging together, not any single factor in isolation. This is why even seemingly minor changes, a different supplier's ingredient with a slightly different pH, a packaging material with different gas permeability, a tweak to a preservative level, can shift how long a product remains safe or acceptable, even though nothing about the product looks different on paper.
Shelf life testing typically combines microbiological, chemical, physical, and sensory testing methods, with the specific combination depending on the product's characteristics and the hazards relevant to it. The goal of the programme is not a single number, but a documented basis for that number that can be defended if a product is challenged, by a regulator, a retailer, or a customer complaint.
Not every product needs a challenge study, but every shelf life claim needs a documented basis, and the growth/no-growth assessment is how that basis gets established.
Intrinsic factors (pH, water activity, preservatives) and extrinsic factors (storage temperature, packaging atmosphere) are assessed against known growth boundaries for relevant pathogens.
Where the assessment clearly shows growth won't occur, or clearly will, a challenge test generally isn't required, since the product's characteristics already answer the question.
For products with characteristics near the growth/no-growth border, a challenge study clarifies the uncertainty and verifies the growth model with real data.
Pathogen challenge studies (inoculated pack) inform use-by, safety, dates. Spoilage challenge studies inform best-before, quality, dates.
A critical practical point: pathogenic cultures must never be introduced into a food processing facility. Challenge studies are conducted only in accredited off-site laboratories or research facilities, never on production premises, for obvious reasons. Spoilage challenge studies follow the same off-site principle, used when the natural incidence rate of a spoilage organism in a product is too low to observe its impact through a standard, non-inoculated shelf life study, but the organism could still be present at low levels in the real product.
A November 2024 amendment to EU microbiological criteria for foods, expanding shelf-life study requirements for ready-to-eat foods, comes into force in just a few weeks.
Amendments to the microbiological criteria for foods under EU Regulation 2073/2005, adopted in November 2024, expand the requirements for food business operators regarding Listeria monocytogenes in ready-to-eat foods, coming into force on 1 July 2026.
Food business operators must either ensure Listeria monocytogenes is undetectable in 25g of RTE food before it leaves the manufacturing facility, or demonstrate via a shelf-life study that levels won't exceed 100 CFU/g throughout shelf life.
The categories of RTE foods this framework applies to are expanded, meaning more product categories now need to choose between the strict undetectable-at-release standard or a documented shelf-life study supporting the 100 CFU/g pathway.
The amendments come into force. Products newly brought within scope need a shelf-life study basis in place by this date if relying on the 100 CFU/g throughout-shelf-life pathway and not undetectable-at-release.
For affected RTE producers, the practical choice is between two paths: ensure Listeria monocytogenes is undetectable at the point of release, which for many products is operationally demanding and may not reflect realistic low-level presence that doesn't grow under the product's actual storage conditions, or invest in a shelf-life study that demonstrates growth stays below 100 CFU/g for the full claimed shelf life, which requires the growth/no-growth assessment and, where the product sits near the boundary, a challenge study. Products newly brought into scope by the expanded categories that don't currently have either basis documented have a hard deadline of 1 July 2026 to establish one.
The output of shelf life testing isn't just a number, it's a decision about which type of date claim the evidence supports.
A use-by date relates to food safety: after this date, the product should not be consumed, because a safety risk, typically pathogen growth, becomes plausible based on shelf life testing. A best-before date relates to quality: after this date, the product may not be at its best in terms of taste, texture, or appearance, but is not necessarily unsafe. The distinction matters for consumers, but also for manufacturers, since the testing basis required differs: a use-by date generally needs the pathogen-focused growth/no-growth assessment and, where relevant, challenge study. A best-before date is generally supported by durability trials tracking sensory and quality attributes over time, sometimes with a spoilage challenge study where natural spoilage organism incidence is too low to observe directly.
Consumer confusion between these two date types contributes significantly to household food waste, with surveys finding a large share of consumers discard food based on dates without distinguishing whether the date reflects a safety or quality consideration. This is the driving logic behind the bipartisan Food Date Labeling Act of 2026 in the United States, which seeks to establish a uniform system distinguishing the two, alongside California's own July 2026 date labelling requirements as an early state-level example, with a federal uniform compliance date of 1 January 2028 anticipated for new labelling rules published in the 2025-2026 window.
For manufacturers, the direction of travel across multiple markets is the same: clearer separation between safety and quality dates, with the testing basis for each documented and traceable. A product currently using a single best-before date where a use-by date would be more appropriate, or vice versa, is worth reviewing now instead of waiting for a labelling deadline to force the issue.
Shelf life testing is relevant to any business launching a new product, reformulating an existing one, or needing to defend an existing date claim.
Businesses needing a documented shelf life basis before a new product goes to market, covering both the date claim and the testing behind it.
Operations needing a shelf-life study basis for products newly in scope of the expanded criteria taking effect 1 July 2026.
Manufacturers changing ingredients, suppliers, or packaging needing to confirm the existing shelf life basis still holds.
Operations with dates set by historical convention and not documented testing, needing to establish a defensible basis.
Manufacturers wanting to extend a current shelf life for commercial reasons, needing study evidence to support the change.
Operations needing to confirm whether their current date type, safety or quality, matches what their testing supports.
We cover the full scope of shelf life study design, from first growth/no-growth assessment through to label-ready documentation.
Assessment of intrinsic and extrinsic factors against known pathogen growth boundaries to determine whether a challenge study is needed.
Design of a durability trial programme covering testing parameters, sampling points, and storage conditions appropriate to the product.
Coordination of pathogen and spoilage challenge studies with accredited off-site laboratories, including study design and result interpretation.
Review of products newly in scope of the expanded Listeria criteria, and design of the shelf-life study basis needed by 1 July 2026.
Review of whether current date types match the testing basis, and what additional testing would be needed to support a different classification.
Assessment of whether an ingredient, process, or packaging change affects the existing shelf life basis, and what re-testing is needed.
Study design to support extending a current shelf life claim, with documentation traceable to the new formulation or process.
Selection of accredited laboratories for microbiological, chemical, sensory and physical testing, and coordination of the testing programme.
Documentation linking study results to the final date claim, traceable to formulation, recipe, and product code for audit and regulatory purposes.
The process follows a defined sequence. Our part of the design and coordination work typically takes 1 to 2 weeks. The study itself runs for the duration being validated.
| Stage | What happens | Our role | Duration |
|---|---|---|---|
| 1. Product and claim scoping | The target shelf life, date type (use-by or best-before), and relevant hazards are identified for the product. | We confirm scope and the claim being targeted. | 1 to 2 days |
| 2. Growth/no-growth assessment | Intrinsic and extrinsic factors are assessed against pathogen growth boundaries. | We conduct the assessment and determine whether a challenge study is needed. | 2 to 3 days |
| 3. Study design | The durability trial and/or challenge study design is finalised, including testing parameters, sampling points, and storage conditions. | We design the study and prepare laboratory briefs. | 3 to 5 days |
| 4. Laboratory coordination | Accredited laboratories are selected and the testing programme is scheduled. | We coordinate with laboratories and confirm timelines. | 2 to 3 days |
| 5. Study execution | The study runs for the duration being validated, plus a margin, under defined storage conditions. | We monitor progress and liaise with the laboratory. | Per study duration + margin |
| 6. Result interpretation | Results are interpreted against the target shelf life and date type. | We interpret results and confirm whether the target claim is supported. | 2 to 3 days |
| 7. Claim documentation | Documentation linking results to the final date claim is prepared, traceable to formulation and process records. | We prepare the documentation package. | 2 to 3 days |
| 8. Label implementation | The date claim is implemented on labelling. | We review the final label for consistency with the documented claim. | 1 to 2 days |
Our gap assessment checks whether your existing shelf life claims would survive being challenged.
The assessment reviews existing shelf life claims against the underlying testing and documentation that supports them, checking whether use-by or best-before dates are traceable to formulation-specific study data, whether a growth/no-growth assessment has been documented for products relying on intrinsic or extrinsic factors and not a challenge study, and whether recent formulation, process, or packaging changes have been evaluated against the existing shelf life basis.
For RTE products sold into the EU, the assessment also checks readiness for the expanded Listeria criteria requirements taking effect 1 July 2026, identifying products that may need a new or updated shelf-life study basis before that date.
We review existing date claims against documented testing basis.
We confirm the basis is traceable to current formulation, recipe, and product code.
We check whether products are newly in scope of the expanded criteria.
We produce a written gap assessment with a prioritised action plan.
For multi-product ranges, we prioritise products newly in scope of regulatory deadlines, such as the EU Listeria criteria, first.
The same gaps appear across shelf life reviews regardless of product category. Knowing where these gaps cluster is the most effective preparation.
A shelf life date inherited from a previous formulation, a similar product, or simply industry convention, without documented testing for the current formulation, has no traceable basis if challenged.
A change to ingredients, suppliers, or packaging that isn't evaluated against the existing shelf life basis can shift the growth/no-growth boundary for a product that was previously near it, invalidating the original study without anyone realising.
A best-before date used for a product where pathogen growth is plausible within the claimed period, or a use-by date used where the relevant consideration is purely quality, doesn't match what the underlying risk and testing basis support.
A product whose intrinsic and extrinsic factors sit close to the growth/no-growth border, relying on the assessment alone without a challenge study to verify it, leaves genuine uncertainty unresolved.
RTE products that will newly fall within the expanded EU Listeria criteria from 1 July 2026, without a shelf-life study basis already in place, face a hard deadline with limited remaining lead time.
A study that runs for less time than the shelf life being claimed, without an accelerated testing methodology validated for that product type, doesn't demonstrate the product remains safe or acceptable for the full claimed period.
Understanding how shelf life testing relates to other verification activities clarifies what it covers and what it doesn't.
| Shelf life testing | Environmental monitoring | HACCP | |
|---|---|---|---|
| Question answered | How long is this product safe/acceptable? | Is the production environment controlled? | Are hazards controlled at each process step? |
| Output | Use-by / best-before date claim | Sampling plan and trend data | Hazard analysis and CCP plan |
| Timing | Pre-launch and after reformulation | Ongoing, routine | Ongoing, with periodic review |
| Our consulting | Shelf Life Testing | Environmental Monitoring | HACCP |
What drives the timeline and cost of a shelf life testing project. We provide a written proposal with a fixed fee after the initial consultation.
Timeline
How long our consulting work takes
Cost factors
What drives the consulting fee
Assessment of intrinsic/extrinsic factors without a full study, for products clearly away from the growth boundary. Typically 2 to 3 days.
Design and laboratory coordination for a new product's shelf life programme. Our consulting work typically takes 1 to 2 weeks, plus the study duration itself.
Review of products newly in scope and design of the required shelf-life study basis ahead of the 1 July 2026 deadline.
Coordination with accredited laboratories for pathogen or spoilage challenge studies, scoped to the laboratory's own fees and timelines.
Assessment of whether a specific change affects the existing shelf life basis, and what, if any, re-testing is needed.
A single-product review requires less work than a multi-product range, particularly where products vary in their proximity to growth boundaries.
A gap assessment only, a full study design and coordination package, or an ongoing reformulation review service each carry different fees. All scopes are defined in writing before work begins.
Fees charged by accredited laboratories for testing are set by the laboratory and are separate from our consulting fees.
Answers to the questions we hear most often from manufacturers establishing or reviewing shelf life claims.
Shelf life testing is the process by which a food manufacturer determines and validates how long a product remains safe and acceptable for consumption under specified storage conditions. It is the manufacturer's responsibility to determine shelf life, and the resulting date, use-by for safety-critical products or best-before for quality-related ones, must be traceable by formulation, recipe, or product code to product development records. Shelf life testing typically combines microbiological, chemical, physical, and sensory testing methods, with the specific combination depending on the product's characteristics and the hazards relevant to it.
A growth/no-growth assessment evaluates a product's intrinsic factors, such as pH, water activity, and preservatives, and extrinsic factors, such as storage temperature and packaging atmosphere, against known growth boundaries for relevant pathogens to determine whether pathogen growth during shelf life is plausible. Where it is clear from these factors that growth will not occur, or that it clearly will occur, a challenge test is generally not required, since the answer is already established by the product's characteristics. Challenge tests are reserved for products whose characteristics sit near the growth, no-growth boundary, where the assessment alone cannot give a confident answer.
A challenge study, also called an inoculated pack study, deliberately introduces a known quantity of a target organism, a pathogen for a food safety study or a spoilage organism for a quality study, into a food product, then stores it under defined conditions and measures how the organism's population changes over time. Pathogen challenge studies relate to use-by, safety-critical, dates, while spoilage challenge studies relate to best-before, quality-related, dates. Because pathogenic cultures must never be introduced into a food processing facility, challenge studies are conducted only in accredited off-site laboratories or research facilities, never on production premises.
Amendments to the microbiological criteria for foods under EU Regulation 2073/2005, adopted in November 2024, expand the requirements for food business operators regarding Listeria monocytogenes in ready-to-eat foods, and come into force on 1 July 2026. Under the existing framework, food business operators must either ensure Listeria monocytogenes is undetectable in 25 grams of RTE food before it leaves the immediate control of the manufacturing facility, or demonstrate, through a shelf-life study, that the level of Listeria monocytogenes will not exceed 100 CFU per gram throughout the product's shelf life. The amendments expand which categories of RTE foods this framework applies to, meaning more products will need a documented shelf-life study specifically addressing Listeria monocytogenes growth potential to use the 100 CFU/g pathway and not the stricter undetectable-at-release standard.
A use-by date relates to food safety: after this date, the product should not be consumed, because a safety risk, typically pathogen growth, becomes plausible based on shelf life testing. A best-before date relates to quality: after this date, the product may not be at its best in terms of taste, texture, or appearance, but is not necessarily unsafe. This distinction is the basis of efforts such as the bipartisan Food Date Labeling Act of 2026 in the United States, which seeks to establish a uniform system distinguishing quality dates from safety dates, since consumer confusion between the two contributes significantly to household food waste.
Shelf life studies typically combine several testing methods depending on the product. Microbiological testing screens for pathogens and spoilage organisms using methods such as real-time PCR and plate counts. Chemical testing measures factors such as lipid oxidation, vitamin loss, and pH changes over time. Sensory testing uses trained panels, and increasingly tools such as electronic nose and tongue devices, to monitor flavour, aroma, texture and colour. Physical testing examines texture, viscosity, and packaging integrity, including gas permeability for modified atmosphere or vacuum packaging. The combination used depends on which factors are most likely to determine when the product becomes unsafe or unacceptable.
Even seemingly minor changes to ingredients, manufacturing procedures, or packaging can affect shelf life, since shelf life depends on the interaction of multiple factors, formulation, process, and packaging together, not any single factor in isolation. A change to a preservative level, a different supplier's ingredient with a slightly different pH, or a packaging material with different gas permeability can each shift the growth/no-growth boundary for a product that was previously close to that boundary. This is why shelf life criteria need to be traceable by formulation, recipe, or product code to product development records, so that a change can be evaluated against the existing shelf life basis and not assumed to be unaffected.
A shelf life testing gap assessment reviews existing shelf life claims against the underlying testing and documentation that supports them, checking whether use-by or best-before dates are traceable to formulation-specific study data, whether a growth/no-growth assessment has been documented for products relying on intrinsic or extrinsic factors and not a challenge study, and whether recent formulation, process, or packaging changes have been evaluated against the existing shelf life basis. For RTE products sold into the EU, it also checks readiness for the expanded Listeria criteria requirements taking effect 1 July 2026.
Our consulting work, designing the study and coordinating with laboratories, typically takes 1 to 2 weeks. The study itself runs for the duration being validated, since a study claiming a 21-day shelf life needs to run for at least 21 days, plus a margin, under real storage conditions, though accelerated testing methods can sometimes shorten this for certain product types. Challenge studies at an accredited laboratory typically add their own scheduling and turnaround time, which is outside our control and depends on the laboratory's availability.
Yes. Study design, growth/no-growth assessment, laboratory coordination, and shelf life claim documentation are all available remotely. The actual testing, sensory panels, microbiological analysis, and challenge studies, is conducted by accredited laboratories, which we help select and coordinate with based on your product and the testing methods required.
You can commission any of these on their own, with an agreed scope and a written quote, without taking on ongoing consulting. See all food safety services.
To establish whether your controls were ever proven capable.
Read about A verification and validation review →Where a pathogen is establishing in the environment.
Read about Listeria and pathogen control support →Where the specification behind the label is the weak point.
Read about A product specification review →Tell us about your product, your target markets and your current shelf life claims. We will tell you exactly what evidence stands behind them, and what's missing.