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United States Department of Agriculture

Agricultural Research Service

Research Project: ENHANCEMENT OF THE QUALITY AND MICROBIAL STABILITY OF FRESH FRUITS AND VEGETABLES WITH EDIBLE COATINGS AND OTHER SURFACE TREATMENTS

Location:

2008 Annual Report


1a.Objectives (from AD-416)
Improve technology that preserves quality, edibility and storability of whole fresh and fresh-cut produce, with emphasis on chemical-free and organic-compatible treatments. Model how fruit coatings influence concentrations of internal gases and, thus, affect quality.


1b.Approach (from AD-416)
Assess potential incidence of disease preharvest to anticipate problems under postharvest conditions. Test antagonistic microorganisms as a decay-control treatment as well as antimicrobial essential oils and natural phytoalexins. Coating formulations will be developed from new or traditional ingredients and analyzed for their ability to block pores in the fruit peel, and reduce microbial populations for intact and fresh-cut produce. Intact fruit will undergo treatments that reduce wound-ethylene in the fresh-cut product. In all cases, affect of treatments on quality will be evaluated.


3.Progress Report
This project aims to extend shelf life, quality and microbial stability of intact and fresh-cut fruit. Work was continued on deploying calcium chloride in fruit cartons (sachets, chlorine dioxide) on a laboratory scale for decay control of tomato and citrus, and pilot plant tests are now planned. Allowable sanitizers and commercial fruit coatings were tested for their effect on eliminating the canker bacteria that causes blemishes on citrus fruit rendering them unmarketable and subject to quarantine (in that they are banned from shipment to other citrus growing areas) and a reduction of the pathogen was observed, but not eliminated. Antimicrobial compounds were screened for efficacy against the canker bacteria, and several food grade candidates were found. Work was also done on laser labeling of fruit, its effect on decay and water loss. Research on fresh-cut pears showed that delayed harvest maturity resulted in better quality. Work on removal of the waxy cuticle layer on fruit for effect on removal of decay organisms showed that decay was reduced on whole fruit and microbial populations were reduced on the fresh-cut product for papaya.

This work relates to National Program 306 Quality and Utilization of Agricultural Products, Component 1 Quality Characterization, Preservation, and Enhancement, Problem Area 1b Methods to Evaluate and Predict Quality.


4.Accomplishments
1. Selection of anti-microbial essential oils. Citrus fruit from Florida are banned from shipment to other citrus growing areas because of the possibility of spreading citrus canker disease. Sanitizers, fruit coating ingredients and essential oils (from citrus peel and other plants), were screened and selected for efficacy against the citrus canker bacteria in vitro. These were then applied to fruit as well as low oxygen, high carbon dioxide atmosphere. The sanitizer peroxyacetic acid, several food grade oils, carnauba wax, the coating component, morphalene, and low oxygen all showed some effect in reducing canker growth in vitro. The most effective sanitizer, essential oil, coating and storage atmosphere will be combined to create a systems approach that is lethal to the canker bacteria, but that does not impair fruit quality so that the quarantine can be rescinded.

This work relates to National Program 306 Quality and Utilization of Agricultural Products, Component 1 Quality Characterization, Preservation, and Enhancement1c, Problem Area 1c Factors and Processes that affect Quality.


5.Significant Activities that Support Special Target Populations
Work on citrus canker elimination from citrus fruit benefits the small citrus fresh fruit grower in rural Florida by lifting the quarantine on their fruit that prevents shipment to other citrus-growing areas.

Work on tropical fruits benefits the small rural and often woman or minority-owned farms in south Florida.


6.Technology Transfer

Number of the New MTAs (providing only)1
Number of Non-Peer Reviewed Presentations and Proceedings7
Number of Newspaper Articles and Other Presentations for Non-Science Audiences3

Review Publications
Jarret, R.L., Baldwin, E.A., Perkins, B., Guthrie, K., Bushway, R. 2007. Diversity of fruit quality characteristics in Capsicum frutescens. HortScience. 42(1):16-19.

Navaro-Tarazaga, M.-L.,Perez-Gago, M.-B., Goodner, K., Plotto, A. 2007. A new composite coating containing HPMC, beeswax and shellac for 'Valencia' oranges and 'Marisol' tangerines. Proceedings of Florida State Horticultural Society. 120:228-234.

Pinnavaia, S., Plotto, A., Narciso, J.A., Baldwin, E.A., Senesi, E. 2007. Flavor and other quality factors of enzyme-peeled oranges treated with citric acid. HortScience. 42(7):1644-1650.

Last Modified: 7/23/2014
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