Purpose: This study is undertaken to evaluate the hygiene conditions of specific sites along fresh blueberry packing lines in Georgia.
Methods: Five fresh blueberry packing establishments in Georgia were selected. A delimited area (100 cm2) on ten selected sites in each establishment was swabbed with sterile sponges in the morning, at lunchtime and in the evening. The sponges were thoroughly rinsed with Dey-Engley neutralization broth, and the broth were subsequently sampled for total aerobic bacteria, yeasts and molds, total coliforms, fecal coliforms and enterococci.
Results: Average aerobic bacteria counts, yeast and mold counts, and total coliform counts on the selected sampling sites ranged from 2.34 to 3.74, 1.90 to 3.36, and 0.60 to 1.31 log CFU/cm2, respectively. Sample source, sample site, and sampling time had a significant influence (P≤0.05) on total aerobic bacteria, yeasts and molds and total coliform counts. The evening samples had the highest microbial counts whilst the morning samples had the lowest counts. Thirty-two out of the 230 (13.9%) sampled sites tested positive for enterococci whilst 20 sites (8.7%) tested positive for fecal coliforms. Seven sites sampled in the morning and evening tested positive for fecal coliforms whereas 6 sites sampled at lunchtime tested positive. Five, 16 and 11 samples collected in the morning, lunchtime and evening, respectively tested positive for enterococci. Berry lugs, rubber belts on color sorters, and pre-mature berry disposing areas had relatively higher microbial counts.
Significance: The study suggests that some sites along the packing lines could be potential sources of blueberry contamination during processing. Sanitation and cleaning practice of blueberry packing houses need to be improved to minimize contamination of freshly packed blueberries.