Physical, chemical and microbiological analyses play important roles in the production of food and beverages to protect consumers from foodborne hazards and to ensure consistent quality at all stages of food processing from raw materials to the retailer’s shelf.
The Global Food Safety Initiative guidance document, 5th edition (section 6.1.21), September 2007, identifies product analysis as a key element of food safety management systems. It requires “…that the supplier prepare and implement a system to ensure that product/ingredient analyses critical to the confirmation of product safety is undertaken and that such analyses are performed to standards equivalent to ISO 17025.”
This article sheds light on the role of analyses along the product life cycle and discusses criteria that may best ensure their effectiveness and added or protective value for the food industry.
Analyses along the Product Lifecycle
Foods and beverages are produced using, to a large extent, natural ingredients such as milk, cereals, fats and oils, starches, minerals and trace elements. Along the value chain (i.e., sourcing and manufacturing, transportation, storage, retail and, finally, consumption), food products are exposed to many risks, which can be grouped as follows:
• Microbiology: pathogens and microorganisms that cause spoilage
• Residues and contaminants: pesticides, heavy metals, mycotoxins, environmental contaminants and veterinary drugs
• Nutrients: deviations caused by ingredient composition and process or human failures as well as deterioration
• Potential side effects of ingredients, such as probiotics
To identify, evaluate, mitigate and manage these risks, food manufacturers employ quality management systems. Their objective is to ensure consumer safety, that is, to eliminate what could compromise product value as well as to promote consumer satisfaction, which includes creating product value and meeting consumer expectations. These systems need to address the complete product lifecycle—development and design, manufacturing as well as consumer experience and feedback (Figure 1).
At each stage, analyses play important roles:
In development and design, raw and packaging materials, intermediates and end products/prototypes need to be specified regarding their chemical, physical, microbiological and functional parameters, all of which need to be validated to ensure fitness for purpose and verified for compliance with all relevant requirements. Analyses during development also play important roles in determining a product’s shelf life (as indicated by the “best before” date) and its open shelf life (as frequently specified in the use instructions, e.g., keep refrigerated after opening, consume within “x” number of days).
In manufacturing, analyses are conducted as in-process testing and quality control (QC); as compliance testing to meet particular legal requirements (e.g., U.S. Food and Drug Administration); and, finally, as environmental microbiological testing. Despite the importance of analyses at each stage of production, testing at this stage can only confirm compliance with a given set of criteria. It cannot replace product and process design or training.
At the consumer end, analyses are employed in post-launch evaluation and monitoring to better understand product properties throughout the product’s shelf life and at the time of consumption, as well as in dealing with consumer complaints and crisis management.
To understand and appreciate the value of analyses, it may help to conduct a critical review, utilizing the value management triangle of Quality – Service – Cost (Figure 2).
Considerations for Consistent Quality of Analyses
People are a company’s greatest asset, and they subsequently play essential roles in determining the quality of analyses. The organization of the team should empower every member to participate in decision making and value individual strength. Supervisors should provide clear leadership and growth opportunities through ambitious assignments. A service culture, supported by adequate training measures, should encourage employees to focus on delivering value to customers and promote team spirit. In such an environment, technical and managerial skills and competencies should clearly be defined and developed. Although the professional environment of laboratories would seem to prioritize scientific and technical detail, management would be wise to dedicate a significant amount of time to the development of personnel.
State-of-the-art technology is the next most important driver of quality analyses. Adequate investment should be allocated in quality budgets to purchase and deploy advanced technology. Such funding is vital to cope with the demand for lower thresholds, an increasing number of samples, faster turnover, more economical use of chemicals and maintenance of compatibility with advanced software. For standard analytical parameters such as limit of detection and limit of quantification (LOQ), the level of precision should be defined in advance, and equipment and test methods should be deployed ready to reach that level. For example, to analyze the level of pesticides in baby food, the LOQ of the liquid chromatography-mass spectrometry (MS)/MS instrument should be significantly below the legal limit of 10 ppb.
Standardized practices and procedures are the backbone of a laboratory and ensure consistent and reliable results. It is vital to train every technician to conduct analyses exactly the same way every time; this includes very basic techniques like weighing, measuring, pipetting, reading of a scale, etc. Particular focus should be spent on sampling (e.g., who, when, where, accessories, environmental conditions like humidity, temperature, sampling sequence for different types of analyses) and sample storage conditions (e.g., temperature, humidity, light). Quality control cards and trend analyses are useful tools to track the performance of a method or a piece of equipment and to detect any deviations at an early stage. Additionally, a preventive maintenance procedure should be in place to ensure the equipment delivers reliable results each time.
Standards of Analyses
International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC) 17025 is the main standard used by testing and calibration laboratories. Originally known as ISO/IEC Guide 25, ISO/IEC 17025 was initially issued by the ISO in 1999. There are many commonalities with the ISO 9000 standard, but ISO/IEC 17025 adds the concept of competence to the equation, and it applies directly to those organizations that produce testing and calibration results. A second release of the ISO/IEC 17025 standard was made in 2005 to align it more closely with the 2000 version of ISO 9001. The most significant changes introduced greater emphasis on the responsibilities of senior management and explicit requirements for the continual improvement of the management system itself, particularly, communication with the customer.
There are two main sections in ISO/IEC 17025—management requirements and technical requirements. Management requirements are primarily related to the operation and effectiveness of the quality management system within the laboratory. Technical requirements address the competence of staff, methodology and test/calibration equipment.
Laboratories use ISO/IEC 17025 to implement quality systems aimed at improving their ability to consistently produce valid results. It is also the basis for validation by an Accreditation Body. Since the standard is about competence, accreditation is simply the formal recognition of a demonstration of that competence based on a documented quality management system that follows the outline of ISO/IEC 17025.
ISO 17025 accreditation should be a minimum requirement of a laboratory. However, it is not a guarantee of correct results, good service or customer satisfaction.
Laboratory Proficiency
Laboratory proficiency testing is an independent, unbiased assessment of the performance of all aspects of the laboratory, both human and hardware, and is an essential element of laboratory quality assurance. With the increasing demands for independent proof of competence from regulatory bodies and customers, proficiency testing is relevant to all laboratories testing food for quality and safety.
In proficiency tests, the laboratory is encouraged to use its usual methods to simulate the testing of a routine laboratory sample as closely as possible. While the outcome of the analysis may be dependent upon the choice of method, it could also be affected by the performance of the laboratory equipment or the competence of the analyst. For this reason, it is important to involve all analysts in any proficiency test program.
Usually, each participant receives a report that allows them to identify their own assessment. Anonymous results and assessments are also listed for all other participants, allowing a laboratory to compare its performance with other laboratories. Reports also contain information on methods used by participants. Laboratories that do not perform satisfactorily in a proficiency test may be required to take remedial action by their Accreditation Body or in-house quality system.
Considerations for Consistent Service
Analytical portfolio. Whether a company operates its own laboratory or uses third-party services, the first consideration will be the analytical portfolio of the laboratory of choice. “One-stop shopping” services help customers who would otherwise send multiple samples to different laboratories to meet their analytical needs. On the other hand, the portfolio offered in a laboratory should be carefully considered, not only with respect to the number of parameters, but also to the matrices for which a method is validated. For example, a method suitable for the analysis of dry milk powder may fail on a liquid dairy product. The cost of developing, implementing, training and maintaining a wide range of test methods can be very high. It is advisable to identify the core competency of the laboratory and, before keeping any analysis in-house, to define a minimum number of samples to be analyzed per week.
Response time. “Time is money” certainly applies to the area of analysis. The result of in-process control may be needed for a customer to release a batch of raw materials or intermediates to the next step of production; the result of QC analyses may be needed to release a batch to the market. Such analyses can particularly delay batch release by days or even weeks, increasing stocks and working capital. To meet customer expectations, it is therefore essential to offer fast reliable test methods, adequate resources (e.g., analysts and equipment) as well as maximum flexibility within the laboratory to accommodate internal and external effects (e.g., holidays, sickness, peak customer demand). As a customer, one needs to be prepared to pay a premium for fast service to compensate for spare resources or incomplete material utilization, like test kits. This is especially true for support needed in emergencies and crises, when instant services should be available at all times, even during weekends.
Considerations for Consistent Cost
Competitive and transparent price structure. Analytical costs are often looked at only from an internal angle, that is, development from one year to the next, frequently linked to an ambitious savings target. This, however, does not take into account the obvious and necessary evolution of the lab, for example, different analytical requirements, new methods or state-of-the-art equipment. A first step to get out of this trap could be a benchmarking of the laboratory’s cost with other labs, which will help to identify major discrepancies. On the high end, these could include methods that the laboratory conducts in a particularly expensive or ineffective way. On the low end, it might be that the method or equipment used is outdated.
Once these variables are identified, an investigation of the total cost of analysis should be conducted, which should include the cost of administration and management, method development, equipment capital and running cost, consumables like chemicals or cartridges as well as the human resources deployed. In doing this, many surprises may come out, for example, the ratio of administration and management cost vs. true analytical cost. Transparency over costs will help the laboratory to reduce overhead and to develop an overall lab strategy including the portfolio, in-house vs. external services and purchasing.
Quality control vs. monitoring. QC in the food industry relates to a program that systematically uses analyses of a defined set of parameters relevant for product release. The objective is to confirm the conformity of a batch with the specification, particularly concerning food safety-related parameters that are analyzed on every batch. On the other hand, food product monitoring is a systematic collection and surveillance of quality parameters, in order to evaluate the long-term compliance of the product with the specification. QC and monitoring are complementary to one another and provide important information to ensure quality and food safety. A risk assessment should be conducted to assign certain parameters to quality control and monitoring, respectively, in order to achieve the best balance between safety/quality and cost.
Central or local/make or buy. In larger national or international organizations, it may be beneficial to establish a central laboratory responsible for conducting sophisticated analyses that require specifically trained analysts, high-tech or expensive equipment or that are rarely requested. The same criteria also apply to the discussion of whether or not to conduct an analysis in-house or to outsource with a third-party laboratory.
Conclusions
Physical, chemical and microbiological analyses play important roles in the production of foods and beverages to protect consumers from any foodborne hazard and to ensure consistent quality at all stages from raw materials to the retailer’s shelf. The value management triangle of Quality – Service – Cost may help to find a balance between necessary analyses and required services at the lowest possible cost. Clear objectives and transparency will help food companies to define their analytical strategy for their consumers and their own benefit.
Christian Mahr, Ph.D. graduated as a food chemist from the University of Wuerzburg, Germany, and received his doctoral degree from the Technical University Munich, Germany on “Structure-activity relationships of bitter compounds.” Following a postdoctoral fellowship at the University of California, San Diego, from 1992 to 2005, he held various positions in R&D and Quality Management at Kraft Intl., Hoechst AG, Onken Dairy and Campbell Soup Company. In 2005, he joined Numico B.V. as Managing Director of Central Laboratories, Friedrichsdorf. Since 2007, he has been Director Quality & Food Safety of DANONE Medical Nutrition Division.