Effect of Sequential Treatment of Warm Water Dip and Low-dose Gamma Irradiation on the Quality of Fresh-cut Green Onions

The effect of warm water dip in combination with irradiation on quality of fresh-cut green onions was studied. Fresh-cut green onions were treated with and without warm water (50 °C for 20 s) and packaged prior to irradiation at 0, 0.5, 1.0, and 1.5 kGy, then stored at 4 °C for 14 d. Color, texture, decay percentage, electrolyte leakage, sensory qualities, and total aerobic count (TAC) were measured at 1, 4, 8, and 14 d of storage. The warm water treatment reduced the TAC by 0.9 log initially but the beneficial effect disappeared during storage. With the test conditions used in this study, the warm water treatment did not provide added benefits for quality improvements. Irradiation at all tested doses reduced TAC and the development of decay and off-odor, improved visual quality, and preserved green color.