title: Warm water treatment in combination with modified atmosphere packaging reduces undesirable effects of irradiation on the quality of fresh-cut iceberg lettuce.
abstract: Fresh-cut iceberg lettuce dipped in either 5 or 47 degrees C water for 2 min was packaged in modified atmosphere film bags and then exposed to 0, 0.5, 1, or 2 kGy gamma-radiation. Dipping cut lettuce in 47 degrees C water for 2 min prior to irradiation reduced antioxidant and phenolic accumulations induced by irradiation. Irradiation at 2 kGy increased cellular leakage and sogginess of cut lettuce dipped in both temperatures. Samples irradiated at 0.5 and 1 kGy had similar firmness and vitamin C and antioxidant contents as the controls after 14 and 21 days of storage except 1 kGy samples dipped at 47 degrees C had lower antioxidant contents than controls at 14 days of storage. Lettuce dipped at 47 degrees C and irradiated at 0.5 and 1 kGy had better overall visual quality and less tissue browning than corresponding irradiated samples dipped at 5 degrees C. These results suggest lettuce treated with warm water and irradiated at 0.5 or 1 kGy had the best sensory quality without significant loss in texture, vitamin C, or total antioxidants.
authors.affiliation: Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA. xfan@arserrc.gov
authors.forename: Xuetong
authors.initials: X
authors.lastname: Fan
authors.forename: Peter M A
authors.initials: PM
authors.lastname: Toivonen
authors.forename: Kathleen T
authors.initials: KT
authors.lastname: Rajkowski
authors.forename: Kimberly J B
authors.initials: KJ
authors.lastname: Sokorai
mesh_terms: D000975:Antioxidants / Q000032:analysis; D002245:Carbon Dioxide / Q000032:analysis; D005514:Food Irradiation; D018857:Food Packaging / Q000379:methods*; D005720:Gamma Rays; D006358:Hot Temperature; D018545:Lactuca / Q000737:chemistry / Q000382:microbiology / Q000528:radiation effects*; D009753:Nutritive Value; D010100:Oxygen / Q000032:analysis; D010636:Phenols / Q000032:analysis; D011786:Quality Control; D014867:Water
chemical_list: D000975:Antioxidants; D010636:Phenols; D014867:Water; D002245:Carbon Dioxide; D010100:Oxygen