Health, safety and even religious demands are ensuring that food and drink laboratory analysts need the very latest in detection technologies. Sean Ottewell reports.
PerkinElmer has announced the results of collaborations with Fukushima University and the University of Tokyo to develop new radiation detection tests in support of ongoing nuclear crisis response efforts in Japan.
Immediately after last March's earthquake that triggered the radiation contamination event in Fukushima prefecture, PerkinElmer assembled and deployed a loan package of sophisticated radiometric detection instruments and expertise for use by front-line researchers in Japan.
The company provided research teams with critical application knowledge and technology platforms including liquid scintillation counters, gamma ray counters and mass spectrometers for measuring uranium, plutonium, iodine, caesium and strontium isotopes in water supplies, fish, vegetables and other produce in affected areas.
Radioactive comtamination
In response to concerns from the local community of Fukushima prefecture, Fukushima University researchers developed the first map of radioactive contamination immediately after the accident. PerkinElmer worked closely with Yoshitaka Takagai, associate professor of analytical chemistry in the division of environmental system management, faculty of symbiotic systems science, Fukushima University.
He said: "Our research team took the initiative to build the first map of radioactive fallout in response to urgent local anxiety and demands for assurance, as well as taking on the additional vital task of detecting soil contamination to guide clean-up efforts. PerkinElmer technology was instrumental in speeding up the formerly labour-intensive radiation screening of large volumes of samples.
Instrument sensitivity
The sensitivity of the instruments also helped in developing protocols for removing topsoil to ensure effective decontamination of public areas such as schoolyards and playgrounds."
The radioisotope centre of University of Tokyo also participated in the urgent task of determining the scope of contamination in the affected areas, as well as devising new methods for detecting radiation in soil, water, and food, to determine their safety and to guide development of decontamination methods, using PerkinElmer equipment.
Toshiyuki Tadenuma, radiation detector group leader, PerkinElmer, commented: "PerkinElmer has also deployed these technologies in collaboration with the national institute of health sciences in Japan, to create screening methods for testing radiation levels in beef products in the affected areas, which will be expanded into other food ingredients."
Robert F Friel, chairman and chief executive officer of PerkinElmer, said: "As soon as the crisis became known, we felt a unique responsibility to offer all possible assistance, as our company has long been a leader in the specific field of radiometric detection, a technology that enables critical applications needed by the Japanese crisis monitoring and remediation teams.
"We quickly identified the technologies and applications that would be required, and rapidly mobilised the needed solutions and expertise to support response efforts, by offering our people and technologies to aid researchers leading contamination detection and clean-up activities."
Directly and indirectly, the use of PerkinElmer equipment by Japanese researchers in response to the nuclear crisis led to such discoveries as: while radioactive iodine is completely gone from affected sites, the bulk of remaining contamination comprises long half-life cesium-134 and -137; and cleaning up radioactive soil depends on varied terrain - and requires different protocols depending on variables such as abundance of site vegetation, and other related factors.
Test water
Specific PerkinElmer technology platforms used by the university teams included: liquid scintillation counter technology used for measurement of radioactive strontium and radioactive hydrogen (tritium), to locate contamination patterns as well as testing environmental water samples; automatic gamma counter technology (WIZARD2) used for 270 sample sequential measurement of gamma-ray nuclear species such as radioactive caesium and iodine, to determine the scope of contamination in the affected areas, as well as devise new methods for detecting radiation in soil, water, and food, to determine their safety as well as to guide development of decontamination methods; and inorganic technology (ELANDRC II ICP-MS) with the necessary broad range of detection limits required for metal contamination (as well as the presence of uranium and plutonium) in drinking water, soil, wastewater and food.
Porcine testing kits
In a separate development, the company has also announced the launch of Porcine Testing Kits for the rapid detection of porcine meat traces by the Halal food certification industry.
The new solution will make it easier, faster and more cost effective to provide confidence in the integrity and authenticity of food products for global markets where Halal certification is required.
The worldwide market for Halal food products represents US$635b (EUR485b) of the US$4 trillion (EUR3.1b) spent annually on food supplies worldwide, with Asian countries accounting for over 60 per cent of that expenditure (Fig. 1).
The Porcine Detection Kits provide Halal-certifying agencies, contract laboratories and food manufacturers with a screening capability alongside existing laboratory-based technologies, providing on-the-spot rapid characterisation of food products.
The fast and easy-to-use kit can provide a positive or negative screening result for the presence of porcine protein/meat/immunoglobulin G (IgG) as soon as 15 minutes, through a simple interface and minimal sample preparation allowing for operation by non-technical users.
Target food pathogens
Agilent Technologies has entered into a cooperative R&D agreement with the US Food and Drug Administration (FDA) to develop new tools to detect and analyse pathogens in food.
The joint R&D effort will also seek to improve DNA-based tools for confirming that seafood is correctly labelled.
The goal of the first part of the project is to develop a novel assay panel to identify subtypes of salmonella in food.
When outbreaks occur, knowing the subtype can help officials quickly identify the source of the pathogen and hopefully limit the number of victims.
The research will focus on using mass spectrometry-based genotyping to quickly identify salmonella subtypes.
"This effort on the part of Agilent is of extraordinary importance to the FDA," said Eric W Brown, director, division of microbiology, FDA.
"We expect this collaboration will be an important step in the development of new and specific tools for tracking bacterial pathogens in foods."
The second part of the agreement - to be carried out in collaboration with both the FDA and the Campden BRI laboratory in the UK - aims to update Agilent's lab-on-a-chip method of DNA analysis to identify fish species.
Agilent's analytical technique can identify species even after the fish has been processed, which generally removes identifying features such as the head, tail and skin.
Mislabelling
The technology is based on the Agilent Bioanalyser, using restriction fragment length polymorphism. The goal is to make this technology fast, inexpensive and simple enough that many kinds of laboratories can use it on a routine basis.
This type of test could detect such things as intentional mislabelling to avoid tariffs and import restrictions or economic fraud where a less expensive species of fish is sold as a more costly species.
"We're very pleased to be collaborating with the FDA, because this work holds tremendous potential for solving some very challenging threats to the safety and integrity of the food supply," said Paul Zavitsanos, Agilent global food safety manager.
"There's real value in applying biological analysis techniques to food safety, and this collaboration advances our shared vision."
Animal carcinogen
Meanwhile new laboratory chemical analyses have found that Coca-Cola, Pepsi-Cola, Diet Coke, and Diet Pepsi contain high levels of 4-methylimidazole (4-MI), a known animal carcinogen. The carcinogen forms when ammonia or ammonia and sulphites are used to manufacture the caramel colouring that gives those sodas their distinctive brown colours, according to the US Centre for Science in the Public Interest (CSPI), the non-profit watchdog group that commissioned the tests. CSPI first petitioned the FDA to ban ammonia-sulphite caramel colouring in February 2011.
CSPI has reiterated its call to the FDA to revoke its authorisation for caramel colourings that contain 4-MI, and in the interim to change the name of the additive to 'ammonia-sulphite process caramel colouring' or 'chemically modified caramel colouring' for labelling purposes.
In response, Pepsi told CSPI that it has switched to a colouring in California that contains much less 4-MI and plans to do the same in the rest of the country.
Particles are key to taste
Shimadzu has launched the SALD-2300 laser diffraction particle size analyser, which measures the size and distribution of particles. The particle size distribution of raw powdered materials is known to have a significant effect on the performance and function of foods and many other products.
As measurement needs are expanding in a variety of fields and domains, Shimadzu has extended the measurement range from 30 nm to 1000 µm to 17 nm to 2500 µm, and developed an instrument that can easily perform highly efficient, sophisticated measurements.
Furthermore, by increasing the sensitivity by a factor of ten over its conventional models, this system accommodates a wide range of particle concentration conditions, from a low concentration 0.1ppm to high concentrations of 200,000ppm. In addition, it is equipped with a continuous measurement function that provides measurements in intervals as short as one second. As a result, the real-time state of particle size distributions that change with concentration or time can now be measured accurately.
Trace quantities of particulate ingredients in foods, red wines, distilled spirits, teas and other beverages have an impact on peoples' refined sensations, and broadly speaking, on 'taste' and 'flavour'. As a result, the hue, texture, smoothness when swallowing, and crispness of beverages are subtly changed by the size and size distribution of trace particles. Yet because the quantity of particulate ingredients is so small, evaluation and quality control with respect to the flavour could often only rely on the sensations, experience, and perception of trained workers.
