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sample. Characterised by its quick This contamination is a screening abilities, GC-MS has been concern and has periodically caused widely heralded as the ‘gold standard’ for outcry among environmental and health forensic substance identification.” advocates. The results from This sophisticated scientific technique, decarboxylation of the which is routinely used by the FDA in the in the presence of ascorbic US to detect dioxin, may well have been acid (), especially under heat successfully employed to trace the source and light. to a single fats manufacturer in the German egg scare of 2012. EU rules allow Contemporary threats and detection no more than a one part per trillion of As little as 20 years ago, three of the dioxin in for human consumption. four most significant foodborne Over a period of two weeks, batches of pathogens – Campylobacter, eggs and a shipment of pork with 1.5 and enterohaemorrhagic E. coli (EHEC) trillionths were found. The German feed- – were unrecognised as causes of mixing company supplied 110 egg farms, . 651 piggeries and other farms in four German states, federal officials stated. “Amid heightened Dioxin and chemically-related concerns about compounds (referred to collectively as dioxin-like compounds or DLCs) are a in many parts of the world, group of environmental contaminants GC-MS comes to the fore as found throughout the world. While German officials have said that eaten a very important analytical occasionally, the excess is unlikely to technique...” make anyone sick, the EFSA suggests that exposure to DLCs may lead to a is today variety of adverse health effects including regarded as the biggest cause of food- reproductive and developmental borne infection in the western world. problems, cardiovascular disease, For example, scientists believe that increased diabetes and increased cancer. contaminated bottled water could As DLCs tend to accumulate in the fat of account for 12% of infections by this food-producing animals, consumption bacterium. Listeria monocytogenes (Lm) of animal-derived , such as meat, is regarded as emerging because the poultry, eggs, fish, and dairy products, role of food in its transmission has only is considered to be the major route of recently been recognised. human exposure to low levels of DLCs. are toxic chemical Part 1: Ensuring food safety and integrity “Applying a qualitative technique in products formed by mould species a detective-like fashion in this crisis including Penicillium, Aspergillus and n recent years, Chinese officials lifelong diseases, ranging from diarrhoeal (FDA) publishes the Food Code, a and that analysis of food and beverage situation was critical. Samples could be Fusarium. These moulds can readily have come under intense public and diseases to various forms of cancer. model set of guidelines and procedures produce is critical. Gas chromatography- checked right back through the food colonise food crops such as cereal grains, international pressure to intensify WHO estimates that foodborne and that assists food control jurisdictions mass spectrometry (GC-MS) is fast chain until analysts reached a point nuts and fruits, either in the field or post efforts to ensure safer food, after waterborne diarrhoeal diseases taken by providing a scientifically sound emerging as the analytical tool of choice where the chemical did not show up in harvest. Consumption of foods produced Imelamine-tainted milk products from together kill about 2.2 million people technical and legal basis for regulating for such forensic food analysis (see An the sample – indicating that this is where from these commodities poses a potential the 2008 scandal in which six babies died annually, 1.9 million of them children. the retail and food service industries, Introduction to…GC-MS in the food it entered,” says Harrison. risk to human health because the and 300,000 babies fell ill, re-emerged in Many world governments, particularly including restaurants, grocery stores and sector, page 62). Similar scares have occurred in the are resistant to various food processes, several stores around the country. those in developed countries, have institutional providers such “Amid heightened concerns about beverage industry, one of the most including heat treatment. This tragedy brought the issue of food established dedicated official bodies to as nursing homes. food safety in many parts of the world, notable being the benzene in soft drinks Microbiology laboratories doing safety under the world spotlight. The develop, monitor and enforce food safety However, in the wake of the dioxin GC-MS comes to the fore as a very episode of the 1990s. Benzene levels are classical testing use specialty gas World Health Organisation (WHO) directives and regulations. poisoning scare in Europe in 2011 which important analytical technique,” says regulated in drinking water nationally mixtures containing carbon dioxide, has stated that foodborne diseases The EU parliament is informed on sparked import bans on some German Stephen Harrison, Head of Specialty and internationally, and in bottled water hydrogen, nitrogen or oxygen to create and threats to food safety constitute a food safety matters by the European farm products, we are reminded that Gases and Specialty Equipment at Linde in the US, but only informally in soft aerobic and anaerobic controlled growing public health problem. Unsafe Food Safety Authority (EFSA). In the the threat to food safety very much Gases. “It is one of few techniques to drinks. Benzene in soft drinks is of some atmospheres in controlled temperature food is the cause of many acute and US, the Food and Drug Administration exists even within mature economies determine exactly what is in a food concern due to its carcinogenic nature. incubators to stimulate and control

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olfactometry – the testing of flavour and smell compounds.

Sophisticated analytical techniques Harrison explains that laws and regulations have tightened up considerably over the years and scientific food analysis techniques are advancing rapidly, to the point where profiling to determine the origin of ingredients is on the way. The FDA, for example, has instituted analytical methods to detect levels as low as 0.25 parts per million (ppm), with the GC/MS method used for screening the presence of melamine and analogues. “These sophisticated analytical techniques were developed by regulatory and compliance laboratories specifically to identify the presence of melamine microbial sample growth that assists with Scientific methods of food analysis and have now become a standard the microbial analysis. first emerged in the mid-19th century methodology,” comments Harrison. In addition to these pathogens and and a variety of analytical techniques are In verifying food ingredients for fungi, there are a vast range of more available. In the 21st century, principally the absence of undeclared additives, contemporary health threats associated four different types of laboratories laboratories also make use of atomic with the presence of , heavy conduct food analysis: ‘in-house’ absorption spectrometry which is a metals, antibiotics and other food laboratories undertaking research and very fast and accurate way to screen for contaminants such as melamine – as development, checking for contaminants contaminants at levels as low as parts earlier mentioned. and monitoring at food per billion, for example for the analysis More than a billion pounds of manufacturers; commercial contract of . Laboratories also pesticides are used in the US alone laboratories, which handle outsourced monitor the authenticity of origin and annually, to control weeds, insects work from the in-house laboratories for adulterations of natural product using and other organisms that threaten or and are independent, often providing nuclear magnetic resonance (NMR), undermine human activities. Although specialised expertise for niche analysis; which compares the food stuff with a this is a necessary process, studies show academic research laboratories; and known sample; NMR requires liquefied that pesticides, which are toxic by design, fourthly, regulatory and compliance helium for its extremely cold property to can cause health problems, such as birth laboratories aligned with food safety activate the super-conductive magnets defects, nerve damage and cancer over a authorities such as the FDA and the essential for this analytical technique. long period of time. EFSA, which conduct investigations into Katrin Åkerlindh, Global Product Together with essential nutrients, food safety incidents. Manager, Specialty Gases, at Linde plants and animals also take up small Specialty gases are used for food concludes, “It’s critical to monitor food amounts of contaminant heavy metal analysis in laboratories around the quality at a variety of different control compounds and can concentrate them. world. Gases are also used with GC-MS points, from the supply of individual This can be harmful as even minute systems to verify food ingredients such ingredients, through the manufacturing quantities of certain heavy metals such as sweeteners, colourings, aromas, the process and during distribution. as lead, cadmium and mercury are addition of glycerol, and any undeclared Impurities occurring in just a few parts recognised to be potentially toxic when additives, to identify isotopic profiles and per million or parts per billion can have consumed by humans. Mercury exposure to assess whether flavours are natural. serious consequences.” gw via food most often occurs when seafood Gases also play an important role in containing mercury is consumed. the assessment of fat content, whether RELATED ARTICLE All of these contemporary threats rely a fat is saturated or unsaturated and Food processing on accurate scientific analysis of food determination of the protein content. Part 2: Increasing dry ice yield in food at various points in the supply chain to Additionally, gases assist with the chilling and freezing, page 40 ensure safety and integrity. very complex chemistry testing of

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