Abstract
Investigations were conducted on fruit surface and juice microflorae from individual oranges removed from processing lines at a manufacturer of bulk citrus concentrate, and at a fresh, unpasteurized juice processor. Testing included aerobic plate counts (APC), total coliforms, fecal conforms, E.coli, and Salmonella. Fruit were removed from three points in the processing line: pre-grading, post-grading and culled fruit. Fruit surface APCs were generally in the range of 103 to 104 colony forming units (cfu) per fruit for both types of processing facilities. Culled fruit surface APCs were 5 to 30 times higher than for pre- or post-graded fruit. APCs for juice were in the range of 10° to 102 cfu/ml for pre- and post-graded fruit, and 105 to 106 cfu/ml for culled fruit. In general, surfaces and juice of defective culled fruit were much more likely to be contaminated with coliforms, E. coli, or Salmonella than non-defective fruit. Preliminary results suggest that removal of culled fruit from the process stream is necessary to reduce problems related to quality and safety. Research is ongoing.
