19-2 |
Chemical and sensorial quality of irradated fruits and vegetables |
X. FAN, USDA-ARS-Eastern Regional Research Center, 600 E. Mermaid Ln., Wyndmoor, PA 19038-8598 Ionizing radiation can be used for disinfestation, shelf-life extension, and spoilage reduction. In recent years, there is an increasing interest in the use of ionizing radiation for the control of foodborne pathogens on the minimally processed fruits and vegetables. The radiation sensitivity of common foodborne pathogens varies among different bacterium species and strains. To achieve a 5-log reduction of E. coli O157:H7, radiation doses of 2 kGy or less are sufficient. However, for inactivating a 5-log of relatively radiation-resistant bacteria such as Listeria, and Salmonella, doses above 2 kGy may be required. At those doses, radiation may cause undesirable changes in sensorial quality of fresh and minimally processed fruits and vegetables. The adverse effects of irradiation on fruits and vegetables include tissue discoloration, softening, and development of off-flavor/off-odor. Other impacts may include loss in nutrients, such as vitamin C. To reduce those adverse effects, ionizing radiation may be used in conjunction with other chemical or non-chemical techniques such as chlorine, ozone, heat shock, calcium infiltration, ozone, growth regulators and modified atmosphere package. This presentation will examine our latest knowledge on the impact of ionizing radiation on texture, flavor/odor, nutrition and appearance in a number of fruits and vegetables, such as lettuce, apples, herbs, and sprouts. Irradiation in combination with other treatments can be used for enhancing food safety without important losses in sensorial or chemical quality of fresh fruits and vegetables by suppression of softening and browning and by enhancement of lethality to the targeted organisms.
Session 19, Emerging technologies for enhancement of fruit and vegetable quality and safety
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