Assuring Fruit and Vegetable Product Quality and Safety Through the Handling and Marketing Chain

NON-TECHNICAL SUMMARY: Fruit and vegetable industries are faced with challenges of food quality, safety and security in the face of world-wide market competition, loss of chemicals for control of diseases and pests, labor uncertainties, and potential natural and man-made contaminations. This study spans from measuring basic properties of biological materials to the development and evaluation of sensing technologies and their application for food quality and safety. <P>

APPROACH: An information search of companies commercially marketing electronic sorting equipment will be performed. Techniques/technology/methodology used and commodities and their quality characteristic being addressed/measured will be documented. Database of fruit and vegetable quality characteristics versus technology and specific parameters capable of detecting such characteristics will be an extension of the commercial industry evaluation (above) and will involve combining both commercial and research-based information to develop a database of technology versus commodity characteristic. Development of fruit tissue quality characteristic sensing systems will require spectroradiometer and multi- and hyperspectral imaging instrumentation for identification of spectra capable of providing valued contrast between desirable and undesirable tissue and other fruit quality characteristics. Structuring lighting, filtering and imaging components to obtain chlorophyll fluorescence images. Coupling spectral image data with fluorescence image data through neural networks and statistical classifiers for fruit characteristic (including insect presence) classification. Identification, evaluation or development of dedicated instrumentation for prototype development. Multi-array biosensor for food safety and biosecurity: The biosensor platform is made of silicon (Si) wafer. An open channel is formed on the center of the Si wafer by the etching method, where the capture zone will be located. The capture zone is coated with primary antibody and situated between two electrodes. Electrical signal is monitored between the electrodes during use of the biosensor. Electrical signal is directly related to bacterial cell concentration. More than one capture zone will be designed, thus, different antibodies can be immobilized on the biosensor surface. Sampling protocol will be developed according to the biosensor design and the type of food to be monitored. It is anticipated that protocols will differ between solid and liquid food and between fresh and processed food. Fouling and shelf-life of the biosensor will be studied under different storage temperatures. Optimum storage time will be identified. Validation of the pathogen sniffer (electronic nose): The pathogen sniffer (electronic nose) designed and developed at Michigan State University will be used in this study. The sniffer will be used to detect E. coli O157:H7 and Salmonella spp. in fresh fruits and vegetables. Fresh produce will be obtained from a local grocery store. Samples will be prepared, chopped, and added with nutrient broth. The sample will be spiked with E. coli or Salmonella stock culture and placed in the test tube for headspace gas measurements by the sniffer. An enrichment procedure will be developed appropriate to the organism and food group, such fruit or vegetable. Various enrichment broths will be evaluated for the most robust gas patterns. Sampling time will be varied. Chemical compounds from the emitted gases will be identified by gas chromatography/mass spectrometry and other appropriate methods.
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PROGRESS: 2002/10 TO 2007/09<BR>
OUTPUTS: This project exists as a direct association with a national-level multi-state research project having the overall focus of defining and measuring engineering properties of fruits and vegetables and the development of concepts and sensors and systems to assure food safety and postharvest quality of commodities. One important general output of this project is the conducting of an annual national meeting at rotating sites to share technology updates and knowledge as well as to tour and meet with specialty crop industry constituents in that region. This helps advance collaboration and also ensures the project is engaged and connected with the clientele the project is meant to support. The specific focus at this station is in the areas of nondestructive sensing; technology for orchard management; and biosensing. Visible, NIR and UV fluorescence spectroscopy and imaging has been studied to evaluate electronic nondestructive concepts for surface and internal commodity defects. Success was demonstrated in the ability to segment disease disorders that are difficult to detect with human eyes. Additionally, various combinations of wavelengths used in transmittance and reflectance modes were identified which showed the potential to detect insect infestation internal to tart cherries and in turn differentiate high-quality cherries versus cherries having plum curculio infestation damage. A low-cost photodiode-based sensor was developed based on early results and successfully compared against laboratory measurement instrumentation. The newest activity under this project has been the involvement and initiation of research in orchard management technology under the national-level effort of engineering for specialty crops to address labor and cost of production challenges. It is expected outputs and knowledge developed from this project will be important in leading to productive outputs under this new important initiative. Multiple biosensor platforms have been researched and developed, including nanotechnology, for rapid identification of food and water borne pathogens. The studies have been successful in creating methods which are both highly selective and sensitive resulting in advancement of the science and engineering and in multiple patents. All areas of research under this project have produced the important additional output of education of graduate and undergraduate students. <BR>TARGET AUDIENCES: Specialty Crop Industries <P>

IMPACT: 2002/10 TO 2007/09<BR>
This project has increased knowledge of the interactions and response between light and tissue and in turn the capabilities of various electronic systems to measure and quantify fruit and vegetable quality characteristics. More specifically, this research has addressed and advanced development of automatic sorting technology which is needed because of reduced labor; importance of providing safe and consistent quality product; and the presence of pests/insects reaching the postharvest stages of production resulting from loss of in-field control methods due to a significant reduction in chemical controls. Development of biosensors capable of rapid detection/analysis improves the flow of product and provides a more immediate response to avoid expansion or escalation of any potential problem. All aspects of this research have, in general, produced the output of education of graduate and undergraduate students. Overall, the impact of this project has been to advance electronic sorting and sensing technology which has the potential to reduce labor inputs and assure final product quality as well as assist with monitoring in-field production parameters vital to efficient and effective orchard management. For US producers to remain sustainable they must be equipped with technology tools that will lead to reduced input costs and maximization of produce quality and safety.