Vol. 119 (2006): Proceedings of the Florida State Horticultural Society
Citrus

Effect of fruit pick up systems on the microbial quality of citrus fruit surfaces

Renee M. Goodrich
University of Florida,

Published 2006-12-01

Keywords

  • Citrus sinensis,
  • Salmonella,
  • Escherichia coli,
  • citrus processing

Abstract

For Florida to effectively compete in the world citrus industry, significant reductions in harvesting costs will be necessary. Mechanical harvesting can be thought of as a twostep process: removal of fruit from the tree and retrieval of fruit from the ground and/or collection area. A citrus fruit pick up machine developed by OXBO International Corporation is being tested for performance and productivity. The machine is being evaluated for its picking up rate, efficiency, field capacity, and its efficiency for removing undesirable fruit and trash. The performance test is being conducted under different ranges of forward speed, orange variety, and grove conditions. A UF-IFAS machine is also being evaluated for the same criteria. This study evaluates the microbiological aspects of mechanically-handled fruit with respect to fruit surface microflora. Three treatments were evaluated: hand-harvested fruit (control), mechanically-harvested and dropped fruit picked up manually from the ground (MH/hand PUfruit), and mechanically-harvested and dropped fruit picked up with the OXBO or UFIFAS pick up machine (MH/machine PU fruit). Microbial analysis included total plate count (TPC), acidophilic organisms (OSA), generic Escherichia coli (as an indicator of potential contamination), and Salmonella. In general, hand-harvest control fruit had similar microbial loads on the surface of the fruit as microbial loads on the MH/hand PU or MH/machine PU fruit. Neither Escherichia coli nor Salmonella were detected in any of the samples. There were substantial differences among the four replicate trials conducted to date, which may have been due to a variety of factors including differing mechanical action of the machines, weather, equipment sanitation, grove location, and tree/fruit treatments during production.