Shelf Life: The Science Behind Food Safety and Quality

A food product’s shelf life is not based on estimation—it is determined through scientific evaluation of how the product changes over time. This process relies on Shelf Life Studies, which assess how long a product remains both safe to consume and able to maintain its quality under defined storage conditions. Product quality is not assessed solely in terms of microbiological safety; it also includes physicochemical stability and the preservation of sensory characteristics, such as taste, texture, and appearance, until the end of the product’s intended shelf life.

These studies follow a structured testing protocol and include microbiological and physicochemical analyses, together with sensory evaluations. The effect of the final packaging is also taken into account, as different packaging materials can significantly influence the shelf life of the same product.

For products with a long expected shelf life, Accelerated Shelf Life Studies are used. These studies simulate more demanding storage conditions, allowing product performance to be evaluated over a shorter period while providing valuable information about its long-term stability. Based on the results of these assessments, manufacturers can determine whether a product should carry a “Expiry” date, which relates to food safety, or a “Best Before” date, which indicates the period during which the product is expected to retain its optimal quality.

At QACSFOOD, shelf life evaluation is part of our comprehensive R&D Support services. Our approach combines Shelf Life Studies, Food Stability Studies, Packaging Compatibility Testing, Sensory Evaluation, and specialized laboratory analyses to provide food manufacturers with reliable scientific data. This enables them to establish shelf life with confidence, document product safety, and develop high-quality products that meet both regulatory requirements and market expectations.

In this presentation, Ioanna Vasilakopoulou, Food R&D Support Specialist at QACSFOOD, explains the scientific approach behind determining the shelf life of food products. She discusses how Shelf Life Studies, Food Stability Studies, and laboratory testing contribute to documenting product safety, preserving quality, and strengthening commercial reliability.

Listen the full presentation here.

Microbiological Risks in Food Production: From Understanding to Prevention

When we think about microorganisms in the food industry, we often associate them with food spoilage or safety concerns. However, not all microorganisms are harmful. Many are naturally present and harmless, while others may even contribute positively to food production. The real challenge lies in understanding which microorganisms are present, how they interact within the production environment, and which ones may influence food safety, shelf life, and overall product quality.

This has led the scientific community to increasingly focus on the study of the production microbiome—the complex ecosystem of microorganisms that coexist within a specific environment. Similar to the human microbiome, every food product and production facility has its own unique microbial community. Understanding these microbial ecosystems provides valuable insights into how microbiological risks develop and how they can be more effectively managed.

Within this context, Metagenomic Analysis has emerged as a powerful technology for investigating microbial communities throughout the entire production process. Through high-resolution metagenomic sequencing, applied to raw materials, water, production surfaces, or finished products, food businesses can gain a much deeper understanding of their microbial environment than conventional microbiological testing alone can provide.

By analyzing microbial DNA, modern sequencing technologies can identify microorganisms with high precision and reveal not only which microorganisms are present, but also how they establish themselves, interact, and potentially spread throughout a production environment. This enables food manufacturers to move from reactive investigation toward proactive risk management.

By combining microbial ecosystem mapping with environmental monitoring, businesses can identify potential microbiological risks before they impact the final product, strengthen hygiene practices, and enhance their overall food safety strategies.

One important application of this approach is the detection of biofilms—communities of microorganisms that attach to surfaces and become increasingly resistant to cleaning and disinfection procedures. Early identification of biofilm formation helps locate hidden contamination sources and supports more targeted corrective actions.

At QACSFOOD, we combine Hygiene Testing, Environmental Monitoring, high-resolution metagenomic sequencing, and expert scientific interpretation through our Metagenomic Mapping Service (MMS). This integrated approach provides food manufacturers with a comprehensive tool for investigating microbiological challenges, evaluating production environments, and implementing preventive strategies that support product safety, quality, and regulatory compliance.

In this presentation, Spyros Markos, Biologist, Food Biotechnologist MSc, Senior Scientific Advisor & Key Account Manager at QACS Lab, explains to The Food Processors team how Metagenomic Analysis is transforming modern food manufacturing.

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Turning Molecular Science into a Strategic Advantage for the Food Industry

As food safety, supply chain transparency, and regulatory compliance become increasingly critical for industry competitiveness, molecular food analysis is emerging as a powerful tool for product control and quality assurance.

With over 100 years of experience in food and feed testing, QACSFOOD has invested in and developed a comprehensive portfolio of molecular services that support the food industry at every stage of the production process. Its team combines expertise in Microbiology, Molecular Biology, Quality Assurance, Quality Control, and Laboratory Testing, delivering reliable analyses alongside scientific guidance aimed at protecting both products and brand reputation.

DNA-based analyses enable the rapid and highly accurate detection of biological hazards, the verification of raw material and final product authenticity, and documented compliance with European and international regulatory requirements. In practice, they serve as a critical tool not only for preventive control but also for the effective investigation of issues that may arise during production.

QACSFOOD’s expertise in DNA technology is built on the use of state-of-the-art systems, including PCR and Real-Time PCR, as well as advanced DNA sequencing methods such as Sanger Sequencing and Next Generation Sequencing (NGS). In parallel, the laboratory is equipped with cutting-edge systems for microbial protein identification. All analyses are performed within an ISO 17025 accredited environment, ensuring accuracy, reliability, and full traceability of results.

One key application of this technology is the microbiological support of production facilities. This includes:

• Rapid and accurate identification of microorganisms, which is the essential first step in evaluating and resolving microbiological issues. Alongside species identification, ecological insights are provided, supporting the identification of contamination sources.
• Microbial profiling through NGS, a revolutionary technology originating from the Human Genome Project, which enables the complete mapping of a sample’s microbiome. Unlike conventional microbiology, it is not limited by culture media constraints. This method can be applied to food and environmental samples (e.g. water, swabs) and is widely used by regulatory authorities such as the FDA in the United States. By analyzing multiple samples within a production facility, businesses can uncover the full microbiome landscape, identifying both immediate and emerging microbiological risks. This allows QC and QA teams to implement targeted corrective actions—moving beyond general cleaning practices to data-driven interventions. Through proper interpretation of results, companies can identify critical control points, optimize processes, and strengthen their food safety systems.
• Rapid and reliable detection of pathogenic and spoilage microorganisms. Pathogens pose a direct risk to public health, while their conventional detection may take several days and yield uncertain results. With Real-Time PCR, accurate results are available within 24 hours. There have been cases where product recalls based on other methods were later proven to be false positives. Spoilage microorganisms, on the other hand, represent a major quality risk—leading to issues such as mold growth in yogurt, gas formation in cheese, or souring in beer. Real-Time PCR enables fast and reliable testing, allowing for quicker product release and reduced risk.

Another major application of DNA technology is food authenticity, a long-standing concern for the industry. High-profile scandals—such as horse meat in minced products, repeated recalls of feta cheese adulterated with cow’s milk, or the substitution of olive oil with lower-cost alternatives—highlight the importance of reliable verification. DNA technology plays a decisive role in uncovering such fraud.

At QACSFOOD:

• The species of meat in a product (beef, goat, sheep, horse, chicken, turkey) can be identified and quantified using Real-Time PCR, while the authenticity of products such as feta cheese can be verified.
• The species identity of a food—whether of animal or plant origin, including fish or herbs—can be determined through DNA sequencing techniques that provide a precise genetic profile.
• Products can be certified as VEGAN or HALAL through DNA-based testing.
• The absence of unwanted allergens—a leading cause of food recalls and a major public health concern—can be verified.
• The geographical origin of a food product, and even the specific olive variety used in oil production, can be authenticated.

QACSFOOD’s molecular analyses cover a wide range of products, including meat and meat products, dairy, composite foods, fruits and vegetables, coffee, beverages, and animal feed. All tests are conducted in ISO 17025 accredited laboratories, ensuring the reliability and verifiability of results.

However, the company’s approach goes beyond analytical testing. QACSFOOD acts as a scientific partner to businesses, offering consulting support and practical solutions that enhance food safety management systems and operational efficiency.

In a landscape where market and regulatory demands are becoming increasingly complex, molecular analysis is no longer just a laboratory service—it is a strategic tool for the sustainable growth of the food industry.

Advanced analytical solutions supporting product safety, transparency, and market trust

Per- and polyfluoroalkyl substances (PFAS) are a broad group of synthetic chemicals that are raising increasing concern. Their exceptional stability and persistence in the environment lead to accumulation in both environmental and biological systems, intensifying concerns about their potential impact on human health.

PFAS are widely used across multiple industries due to their resistance to heat, water, and grease. They can be found in a variety of applications, including food packaging materials, non-stick cookware, cosmetics, textiles, and other consumer and industrial products. This widespread presence, combined with their persistence, has placed PFAS under increasing regulatory scrutiny. As a result, PFAS testing has become an essential tool for industries such as food and cosmetics, where product safety, regulatory compliance, and consumer trust are critical. The ability to detect and assess PFAS enables businesses to better understand potential risks, ensure compliance with regulatory limits, and support product claims and safety documentation. In this context, the detection and evaluation of PFAS are no longer just a matter of compliance, but a critical component of risk management. Businesses are increasingly required to demonstrate product safety, meet regulatory expectations, and ensure transparency towards the market.

At QACSFOOD, we provide specialized PFAS testing solutions, supporting the industry in the detection, identification, and evaluation of these substances across a wide range of materials and applications.

In accordance with Regulation (EU) 2025/40 on packaging and packaging waste, QACSFOOD performs PFAS determination analyses in packaging materials, supporting compliance with current and emerging European legislation. Our services are fully aligned with evolving regulatory requirements and continuously updated in line with scientific developments.

Our testing services include:

• Targeted PFAS analysis
• Identification and quantification of a wide range of compounds
• Determination of Total Fluorine (TF) and Total Organic Fluorine (TOF)
• Complementary analyses, such as heavy metals, in line with European limits
• Support for compliance with EU regulatory requirements

Our approach is based on advanced analytical techniques and accredited methods, ensuring reliable results and the scientific documentation required for informed decision-making. By combining scientific expertise with a strong understanding of the regulatory landscape, QACSFOOD transforms PFAS testing into a practical tool for risk management, compliance, and strengthening business credibility in today’s market.

Listeria Is Not Rare. It Is Persistent.

What surveillance data really show

Recent surveillance analyses by EFSA highlight something that may seem contradictory at first: detection rates of Listeria monocytogenes in foods remain relatively low, while cases of listeriosis continue to rise steadily across Europe.  This shows that the real issue is not how often the pathogen appears, but how consistently and persistently certain strains survive — mainly in ready-to-eat foods and products with a long shelf life. Simply put, Listeria does not need to appear often. It just needs to stay. “Listeria is not a problem because it appears often, but because it establishes itself and persists.” Listeria is not highly aggressive, but it is extremely adaptable. It can survive refrigeration, elevated salt levels and complex microbial ecosystems, taking advantage of small gaps in cleaning procedures, equipment design or production flow. Its strength is not speed, but endurance—and its ability to return.

What has changed in the regulatory approach

For years, risk management focused primarily on the final product. Absence in 25 g at production or on the market was considered a sufficient indicator of safety. This approach was based on the assumption that a product remains microbiologically stable throughout its shelf life. Today, we know this assumption is not always safe. Food microbiology is not static; it is dynamic and evolves over time. The European regulatory framework has not changed fundamentally. Regulation (EU) 2073/2005 remains the cornerstone of microbiological criteria. What has changed is how it is applied in practice. Shelf life is no longer treated merely as a commercial decision, but as a critical risk management tool. Food businesses are now required to demonstrate that, under reasonably foreseeable storage and distribution conditions, Listeria levels will not exceed acceptable limits by the end of the declared shelf life. When such evidence cannot be provided, applying the stricter criterion of absence in 25 g throughout the entire shelf life is not excessive—it is necessary.

Why shelf life is not just a number

In practice, this shift translates into the growing importance of shelf-life studies and challenge tests. These are not extreme scenarios, but tools that describe realistic product behaviour. If Listeria is present, how will it evolve over time? Will it remain stable, or will it grow—and under which conditions? Particular attention is required for products traditionally perceived as “safe,” such as white brined cheeses, ready-to-eat foods, and products packaged under vacuum or modified atmosphere. In these cases, the issue rarely lies in the formulation itself. It lies in microbiological behaviour over time—in subtle pH changes, interactions with background microflora, and temperature deviations during distribution.

When the source is not the product, but the environment

According to technical guidance and observations from the European Union Reference Laboratory for Listeria monocytogenes, many recurring detections are not due to repeated raw material contamination, but to established populations within the production environment. Wet areas, drains, conveyor lines, and hard-to-clean equipment can act as reservoirs, allowing the pathogen to re-emerge periodically. “The critical question is not whether Listeria was detected, but where it comes from—and why it keeps coming back.” In this context, conventional environmental monitoring alone is often insufficient. Strain-level analysis, such as whole genome sequencing (WGS), combined with integrated evaluation of product and environmental data, enables links between detections, sources, and recurring patterns. Tools such as Microbiome Mapping Studies (MMS) are increasingly part of the discussion, supporting more proactive control strategies.

What this means in practice for the food industry

Food safety today is not judged by whether a single inspection was passed. It is judged by whether a company can scientifically justify why it does not expect a problem tomorrow. Moving from compliance to prediction is not a luxury — it is a sign of industry maturity. At QACSFOOD, this approach is reflected in a combination of tools: product microbiological testing, shelf-life studies, challenge tests, strain analysis using whole genome sequencing (WGS), and targeted environmental mapping through microbiome mapping of the production area (MMS). The goal is not simply detection, but understanding risk — and preventing it before it becomes a problem for the product, the business, and ultimately the consumer.

Metagenomic Mapping Service (MMS): Turning Environmental Microbiomes into Actionable Intelligence

From Detection to Understanding

Environmental monitoring has long been a cornerstone of quality assurance and safety programs. However, traditional culture-based methods and targeted molecular tests provide only a partial and often delayed picture of microbial risks. In today’s complex production environments, manufacturers need more than detection — they need understanding.

QACS’ Metagenomic Mapping Service (MMS) represents a next-generation approach to environmental monitoring. By combining deep microbiological expertise with Next-Generation Sequencing (NGS) and advanced bioinformatics, MMS delivers a comprehensive, data-driven view of microbial ecosystems within production facilities. This enables proactive risk management, faster root-cause analysis, and smarter hygiene strategies.

What Is Metagenomic Mapping?

Metagenomic Mapping is the study of all genetic material recovered directly from environmental samples. Unlike classical microbiology or targeted PCR methods, metagenomics does not rely on culturing or predefined targets. Instead, it captures the entire microbiome, including:

• Cultivable and non-cultivable microorganisms
• Background flora and spoilage organisms
• Pathogens and indicator organisms
• Persistent strains and biofilm-associated microbes

The result is a high-resolution microbial map that reflects the true biological reality of your production environment.

Why Traditional Environmental Monitoring Falls Short

Conventional swabbing and plating approaches typically:

• Detect only a small fraction of existing microorganisms
• Miss stressed, VBNC (viable but non-culturable), or slow-growing organisms
• Provide fragmented data that is difficult to interpret holistically
• React to contamination events instead of preventing them

MMS overcomes these limitations by offering full-depth microbial insight, transforming environmental monitoring from a reactive compliance activity into a strategic quality tool.

The QACS MMS Approach: From Sample to Strategy

QACS’ Metagenomic Mapping Service follows a structured, end-to-end workflow designed for real-world manufacturing environments:

1. Strategic Sampling Design

Samples are collected from all critical control and risk-relevant areas, including:

• Food contact and non-food contact surfaces
• Drains, air, water, and difficult-to-clean niches
• Equipment, transfer points, and traffic zones

Sampling strategies are customized based on process flow, product risk, and historical QA data.

2. High-Resolution NGS Analysis

Total DNA is extracted from each sample and sequenced using Next-Generation Sequencing technologies. This reveals the complete microbial composition at each location — not just what grows on a plate.

3. Microbiome Mapping & Data Integration

By combining results from all samples, QACS generates a facility-wide microbiome map that highlights:

• Microbial hotspots and reservoirs
• Routes of contamination and cross-contamination
• Biofilm-associated communities
• Persistent or recurring microbial populations

4. Advanced Data Interpretation

Raw data alone has limited value. QACS transforms sequencing results into actionable insight using:

• Metadata correlation (zone, time, process step)
• Heatmaps and trend analysis
• Comparative and retrospective analysis
• Expert microbiological interpretation

5. Actionable Reporting & Corrective Guidance

Clients receive a clear, decision-oriented report that includes:

• Interpreted results, not just taxonomic lists
• Identified risks and contamination pathways
• Practical recommendations for sanitation, zoning, and process improvements
• Support for root-cause analysis in case of QC failures

Key Benefits of MMS for Manufacturers

Metagenomic Mapping Service empowers QA/QC and food safety teams to:

• Gain full visibility of microbial populations before they impact products
• Identify hidden risks missed by routine monitoring n- Track contamination sources proactively
• Validate and optimize sanitation and hygiene programs
• Strengthen preventive controls and environmental monitoring plans
• Reduce recall risk and improve overall quality confidence

MMS vs. Classical Molecular Mapping

While molecular mapping approaches focus on selected organisms or genetic markers, MMS delivers:

• Unbiased, full-microbiome coverage
• Higher sensitivity and resolution
• Detection of emerging or unexpected risks
• Deeper insight into microbial ecology and persistence

This makes MMS a powerful evolution of environmental monitoring rather than just an incremental improvement.

Conclusion: From Data to Confidence

In an era of heightened regulatory scrutiny and brand vulnerability, understanding your production environment is no longer optional. QACS’ Metagenomic Mapping Service transforms complex microbial data into practical intelligence — helping manufacturers move from reactive problem-solving to proactive quality control.

By revealing what traditional methods cannot see, MMS enables smarter decisions, stronger preventive strategies, and greater confidence in product safety and quality

Certified Olive Oil Analyses by QACSFOOD

QACSFOOD is an approved laboratory of the International Olive Council (IOC) and is certified by the Hellenic Accreditation System (ESYD) in accordance with ISO/IEC 17025. This certification and recognition framework confirms that our olive oil testing services meet the highest international standards of quality, competence and reliability.

Within the scope of IOC recognition, QACSFOOD performs Sensory Analysis, including the Organoleptic Assessment of Virgin Olive Oils, using internationally accepted methodologies. Sensory testing plays a key role in quality verification and olive oil classification, supporting compliance with IOC requirements and market specifications.

In addition, IOC recognition extends to Residues and Contaminants Testing for olive oil, which is essential for assessing product safety and regulatory compliance. These analyses enable the detection of potential chemical residues or contaminants, supporting conformity with international legislation and trade requirements.

Through the combined application of certificated olive oil analyses, sensory evaluation and residues & contaminants testing, under IOC approval, QACSFOOD provides reliable technical evidence of quality and safety, supporting producers, bottlers and exporters in market access and certification processes, including the issuance of an official IOC Certificate, where applicable.