Instrumentation challenges

Food safety regulations vary around the world, requiring test methods for different pesticides, drug residues and pass/fail thresholds. “This regulatory process is not transparent,” says Nigel Skinner, European Market Development, Agilent Technologies. “Food safety equipment manufacturers will not know about a change in a regulation (i.e. change in detection limits for a drug residue) until about a month before the new regulation comes into effect.

“And while government regulators are keen to detect as small an amount of target as possible, food companies would like higher thresholds with the implication of a smaller number of failures,” says Skinner. “The EU regulatory environment also favors regulating in cases of potential risk, whereas the U.S. regulates after proven risk”—a very significant difference in the testing protocols used by each region.

“Each food supplier, such as Kraft or ADM, also has different requirements,” says Tore Fossum, technical director at Mettler Toledo, making it more complicated for instrument suppliers to provide generic systems. They want instruments that can perform their specific set of measurements reliably long-term. They want instruments that will have a long service life, are easy to use and are cost-effective.

“We see an increasing focus on broad screening approaches that look for a large number of compounds in a single analysis,” says Tisserand. “We also see an increasing focus on establishing tests based on biological activity, rather than chemical identity. For example, testing for endocrine disrupting activity or beta-agonist activity in a sample rather than targeting specific chemicals.”

The net challenge is that instruments need to analyze a greater number of compounds in less time. Part of this can be accomplished with simpler and more efficient sample preparation techniques, increased automation, and smarter software-analysis systems. There is also continued growth in the development of analytical instrumentation technologies, such as time-of-flight mass spectrometry, which offers significant throughput and analytical advantages.

Mettler-Toledo’s C30 Karl Fischer Coulometer provides fast and precise water determination in food and beverage samples.

Sample preparation for food and beverage measurement analyses is particularly involved. “By its very nature, food is not particularly well-shaped to be injected directly into a chromatograph or mass spectrometer,” says Varian’s Debusschere. “Food safety labs look for cost-effective and robust sample prep techniques that allow them to deal with a wide variety of sample matrices, from fruits and vegetables to meat, fish or olive oil.”

“Foods are generally more involved than simple beverages,” agrees Agilent Technologies’ Worldwide Food Industry Manager Paul Zavitsanos. “Coffee and tea are exceptions, but generally high solids and high fat foods present more testing challenges.”

Just working with the various matrices that constitute foods and beverages can be troublesome for instrumentation measurement protocols. Liquids are a hazard with electronic equipment while fine powders can become lodged in mechanisms or create static electricity, says Ian Cziesnuski, technical director for Weighing Products at Mettler Toledo. “Government regulators

Substances Measured Well-established test protocols exist for most food and beverage contaminants with most development focused on how to measure multiple contaminants in the same run.

Sample preparation techniques automated to the highest degree possible are a key to integrating the overall future demands of the food and beverage safety measurements process, according to Jay Gandhi, business development manager for Ion Chromatography at Metrohm USA. “Specific throughput, measurement accuracy, resolution, ease of measurement, and the cost effectiveness of the food safety measurements all depend upon how well the samples are prepared,” he says.

There’s also a growing “need for reference materials, especially in mycotoxin testing, but for other areas of food as well,” says Agilent’s Skinner. “These reference materials consist of different food matrices with a pre-defined level of a particular contaminant.” Existing test protocols also need to be adapted to meet the needs of ever more complicated food matrices, such as those involving nanoparticle contamination.

Improvements have been seen in sample prep and food safety measurements over the past ten years, says Debusschere. “More specific and easy-to-use sample prep procedures have been developed,” he says. “More sensitive and accurate instruments have been developed, and modern computers with capabilities that could not have been dreamed of 15 years ago are now commonplace. But despite these improvements, significant advances remain possible in assisting food testing labs to answer daily challenges.

Metrohm’s 844 is the first compact UV-Vis IC system. It is useful in determining the ionic composition of foods and beverages, such as caffeine in colas.

Just three months ago, the CDC issued a report stating that the safety of the U.S. food supply has actually declined over the past three years. According to the report, in 2008, 16 of every 100,000 people in the U.S. had lab-confirmed cases of salmonella infections. In 2005, these same data were 14 people per 100,000.

“The system needs to be modernized to address the challenges of the globalization of the food supply chain,” said David Acheson, associate commissioner for foods at the FDA.

The individual nature of new pesticides, herbicides and additives by themselves do not represent a major challenge to current analytical instrumentation techniques. The key challenges lie in their growing number and differing nature. “The difficulty resides in efficiently extracting out of mixed fruits or vegetables such a wide array of different organic molecules to identify and quantify them in a single analytical run,” says Varian’s Debusschere.

So should the public feel comfortable in the current level of food and beverage safety measurements? In general, yes, according to the respondents of a Laboratory Equipment reader survey and instrument manufacturers. According to the survey: 1) food quality has improved, 2) measurement budgets have increased, 3) researchers are testing for more substances, 4) they’re measuring more samples, and 5) they’re measuring to tighter specs.

Are there likely to be food safety issues in the future? “Yes,” says Agilent’s Zavitsanos. “Constant vigilance and technology will not solve the issue, just as it does not for other crimes, but we can make it more difficult to do and restrict the act to fewer people.”

Food Safety Instruments Analytical tools are the workhorses in determining the specific contaminants in food safety measurements, with most samples measured initially with basic lab equipment.

“We work to ensure that the breaches in the food safety net are small and low impact,” says Zavitsanos, “but no one expects the issue will retreat forever.”

For more information, contact:
• Chris Conner, Varian, chris.conner@varianinc.com
• Tore Fossum, Mettler Toledo, tore.fossum@mt.com
• Jay Gandhi, Metrohm USA, jgandhi@metrohmusa.com
• Jeff Tarmy, Waters Corp., jeff_tarmy@waters.com
• Paul Zavitsanos, Agilent Technologies, paul_zavirsanos@agilent.com