Source: www.tehrantimes.com

Researchers at the United States Department of Agricultures Food Safety Intervention Technologies Research Unit report that the application of zinc oxide (ZnO) nanoparticles in food systems could prove to be an effective means to inhibit certain pathogens. In a study, scientists evaluated the antimicrobial activity of zinc oxide quantum dots (QDs), nanoparticles of purified, powdered ZnO. The team stated that ZnO QDs were utilized as a powder bound in a polystyrene film (ZnO-PS) and suspended in a polyvinylprolidone gel (ZnO-PVP). Bacterial cultures were inoculated into a growth media of tryptic soy broth (TSB) or brain heart infusion broth (BHIB) or liquid egg white (LEW) and incubated at 22C.

LEW was chosen for the study because both the physical and functional properties of liquid egg products are sensitive to thermal treatments and because occurrences of egg-related Salmonellosis have heightened concerns for the safety of egg-related products. Results indicate that the inhibitory efficacies of ZnO QDs against three pathogens were concentration-dependent and also related to the type of application. The ZnO-PVP (3.2 mg ZnO/ml) treatment resulted in 5.3 log reduction of L. monocytogenes and 6.0 log reduction of E. coli O157:H7 in growth media after 48 hours of incubation, compared with the controls.

Website: www.ap-foodtechnology.com

Researchers at the Agricultural Research Service (ARS), of the United States Department of Agriculture (USDA), have developed a prototype pressure chamber and camera system that can find microcracks (very small cracks) in fresh eggshells. This device could help the egg industry find microcracks that often go undetected during grading, claim the researchers at ARS Quality and Safety Assessment Research Unit (QSARU) and Egg Safety and Quality Research Unit (ESQRU). The ARS team that developed the device comprised food technologist Ms. Deana Jones at ESQRU, and engineers Mr. Seung Chul Yoon, Mr. Kurt Lawrence and Mr. Bosoon Park, technician Mr. Allan Savage and image analyst Mr. Jerry Heitschmidt at QSARU.

The technology emulates human graders who squeeze the egg along suspected cracks to see if it opens. A prototype chamber was built that uses a brief negative pressure to slightly pull the eggshell outward to expose any existing cracks that may be present, without causing cracks in intact eggs. A camera system then takes a picture before and while the pressure is applied to see if the shell is cracked. The system detected 99.4 per cent of eggshell cracks, says Mr. Lawrence, while recording almost no false positives only 0.3 per cent. In comparison, professional human graders exhibited an 85.8 per cent crack detection rate and 1.2 per cent false positives.

Source : www.ars.usda.gov

In Germany, experts from five different research institutes came together two years ago to develop a scanner to evaluate the quality of meat. Funded by the German Federal Ministry for Education and Research, the FreshScan project is headed by the Fraunhofer Institute for Reliability and Microintegration, and brings together researchers from Max Rubner Institute, Ferdinand Braun Institute for High Frequency Technology, Leibniz Institute for Agricultural Engineering Potsdam-Bornim and the Technical University of Berlin. The team employed processes based on laser technology that could read and document the freshness of raw meat. Within the project, a usable experimental model made up of an intelligent label and a hand scanner has been developed. The label functions as a type of running sheet and documents the condition of meat from the slaughterhouse to the point of sale. Additionally, the temperature can be continuously monitored and recorded, ensuring any interruption to the cool chain is documented. The scanner reads the meats condition and simultaneously records it in the intelligent label.

The concept builds on two approaches, firstly by focusing on the food itself and secondly on the logistics of the processing chain, the foodstuffs history is transparent at all steps and can be traced back if necessary. Various functions can be chosen via a touch screen that also displays the analysed measurements. The functional system is currently being tested and optimized as a pilot solution for pork. After the implementation of any required modifications, it could also be used commercially for other types of perishables. Contact: Dr. Volker Groer, Fraunhofer Institute for Reliability and Microintegration, Germany. Tel: +49 (30) 4640 3250; E-mail: volker.grosser@izm.fraunhofer.de; Or Mr. Georg Weigelt, Fraunhofer Institute for Reliability and Microintegration, Gustav-Meyer-Allee 25, Berlin 13355, Germany. Tel: +49 (304) 6403 279; E-mail: georg.weigelt@izm.fraunhofer.de.

Source: cordis.europa.eu

The bar code label is based on the employment of an ink that is nearly invisible, but which turns red when the food is contaminated; the colour change on the bar code prevents the product from being scanned at the checkout counter. The labelling thus establishes an irreversible, tamperproof archived signal in any applicable database. While there are other thermochromic indicators on the market, these are expensive and lack the archival feature required by regulatory agencies to track and trace products on a global scale. The colour changing bar code is cost-effective at US$0.04 per label.

Source: www.fnbnews.com

IFM Electronic Ltd., the South African arm of the process optimization and control company IFM Electronic GmbH, is offering T series full-metal inductive sensors, which have been specifically designed for the food industry. Application tests such as temperature/shock, 1,000 hour long-term and steam boiler tests have proved the suitability of these sensors. The threaded body and the sensing face of the one-piece housing are made of stainless steel, leading to longer sensor life and reducing machine downtime.

The M12, M18 and M30 sensors provide sensing ranges of 3, 5 and 10 mm at 0-100C temperature. High ingress resistance is ensured by the choice of IP67/IP68/IP69K ratings, while the newly developed EVT series connectors, certified by ECOLAB, prevent ingress of moisture into the nut or cable. The asymmetrically acting vibration protection holds the nut tight in its position, guaranteeing an optimum and permanent seal. Contact: Ms. Celia de Beer, IFM Electronic Pty. Ltd., Postnet Suite 279, Private bag X8, Elardus Park, 0047 South Africa. Tel: +27 (12) 450 0370; Fax: +27 (12) 345 5145; E-mail: info.za@ifm.com; Website: www.ifm.com.

Source: www.instrumentation.co.za

Researchers at Iowa State University, the United States, have developed a technique to test for the presence of Salmonella that may give better answers faster. Developed by Mr. Byron Brehm-Stecher, assistant professor in food science and human nutrition, and his graduate student Mr. Bledar Bisha, the process begins with testing the food, in most instances produce, with a strip of adhesive tape. The tape is applied to the produce, then carefully removed, taking a sample of whatever is on the skin of the produce. That sample is then put on a slide and soaked in a special warm, soapy mixture that contains a genetic marker that binds with Salmonella and gives off a fluorescent glow when viewed under an ultraviolet light this genetic marker approach is called fluorescent in situ hybridization (FISH). FISH technique can tell investigators if the produce is contaminated with Salmonella in about 2 h, while current methods of detecting Salmonella take 1-7 days.

The tape-FISH technique can also be used to test produce not suspected of being contaminated, but the volume of produce that would need to be tested may make this impractical. However, the technique could be valuable as a basic research tool. Researchers could study how Salmonella and other types of organisms interact on produce surfaces, explains Mr. Brehm-Stecher. Contact: Mr. Byron Brehm-Stecher, Food Science and Human Nutrition, Iowa State University, United States of America. Tel: +1 (515) 2946 469; E-mail: byron@iastate.edu.

Source: www.public.iastate.edu

Researchers at Purdue University, the United States, report to have developed a new method to determine melamine levels in whole milk and milk powder. Led by Prof. Graham Cooks, the detection technique is based on ambient ionization utilizing a low-temperature plasma (LTP) probe combined with tandem mass spectrometry (MS/MS) This highly sensitive assay is claimed to be the fastest technique yet. According to Prof. Cooks, this technique allows detection and quantitative assessment of the industrial chemical in milk powder, whole milk and other products at levels down to low parts per billion in analysis times of about 25 seconds.

Prof. Cooks stated that ambient ionization methods, such as the low-temperature plasma ionization employed by the Purdue group, can greatly reduce the time-intensive and sometimes difficult prerequisites of mass spectrometers. Prof. Cooks explains that the ionization source of the research project was developed as a general method, not aimed at melamine, with the melamine experiments completed in about 10 days. A patent has been applied for in relation to the detection method, while discussions with regard to its commercialization are ongoing. Further, the research team has been involved in many other food safety related projects, including studies focused on pesticide residues, components in olive oil and natural sweeteners.

Source: www.ap-foodtechnology.com

In the United States, researchers at ARS National Peanut Research Laboratory have developed a new technology to facilitate the peanut industry grade peanuts faster and more accurately. An engineer, Mr. Hank Sheppard, and research leader Mr. Marshall Lamb uncovered that using X-ray technology to grade peanuts delivered a 98-99 per cent accuracy rate and is faster than official peanut grading methods 7 minutes versus 20 minutes per sample. Official peanut grading is labour-intensive, requiring 3-6 people to hand shell, pick, sort and grade each nut.

Another processing problem addressed by ARS research is peanut moisture. Nuts must have a moisture content of 10 per cent or less to be suitable for further processing and shelling. The ability to determine moisture before grading begins would allow processors to divert high-moisture nuts for further drying instead of discarding them. At present, peanuts are shelled and the moisture content is then determined. An engineer at NPRL, Mr. Chari Kandala, developed an automated in-shell moisture detection system utilizing radio frequency that could work in tandem with the X-ray grading unit to provide peanut processors a more efficient operation.

Source: www.ars.usda.gov