The goal of this work was to evaluate the effect of hydrogen peroxide (H2O2) and sodium dichloroisocianurate (NaDCC) sanitizers on the shelf-life of fresh-cut onion, based on the microbial development and physical and physical-chemical characteristics. The onions were washed, peeled and sliced. The following treatments were tested using three randomized blocks: H2O2 (2%), H2O2 (4%), H2O2 (6%), NaDCC (50ppm) and NaDCC (100ppm). The slices were packed and stored at 4ºC for 7 days, after sanitation. One package for treatment was used daily and the following variables were evaluated: standard counting of mesophile aerobic microorganisms, total counting of psychrotrophs aerobic microorganisms, moulds and yeasts, total coliforms at 35ºC and 45ºC, total soluble solids (TSS), pH, titratable acidity (TA), firmness and mass loss. Lower counting of mesophile aerobic were found in slices treated with H2O2; all treatments, but control, were effective in decreasing psychrotroph aerobic and total coliforms at 35ºC; coliforms 45ºC were not found in slices of any treatment; only H2O2 (4%) and H2O2 (6%) treatments decreased the values of moulds and yeasts; the treatments did not affect the TSS and mass loss; NaDCC treatments promoted higher pH; lower TA were found in slices treated with H2O2 (4%), H2O2 (6%) and NaDCC (50ppm) and higher firmness were obtained in slices treated with H2O2 (4%) and H2O2 (6%). From the results it is concluded that H2O2 (4 and 6%) was more effective sanitizer for fresh-cut onions than NaDCC; according the analyzed parameters, the fresh-cut onion was held in proper edible conditions for 7 days after processing, including the control (without sanitizer).
Onion; minimally processed; sanitizers; microorganisms