title: Natural surface coating to inactivate Salmonella enterica serovar Typhimurium and maintain quality of cherry tomatoes.
abstract: The objective of the present study was to investigate the effectiveness of zein-based coatings in reducing populations of Salmonella enterica serovar Typhimurium and preserving quality of cherry tomatoes. Tomatoes were inoculated with a cocktail of S. Typhimurium LT2 plus three attenuated strains on the smooth skin surface and stem scar area. The zein-based coatings with and without cinnamon (up to 20%) and mustard essential oil or a commercial wax formulation were applied onto tomatoes and the treated fruits were stored at 10 °C for up to 3 weeks. Populations of S. Typhimurium decreased with increased essential oil concentration and storage duration. S. Typhimurium populations on the smooth skin surface were reduced by 4.6 and 2.8 log colony forming units(CFU)/g by the zein coatings with 20% cinnamon and 20% mustard oil, respectively, 5h after coating. The same coating reduced populations of S. Typhimurium to levels below detection limit (1.0 log CFU/g) on the stem scar area of tomato during 7 days of storage at 10 °C. Salmonella populations were not reduced on fruit coated with the commercial wax. All of the coatings resulted in reduced weight loss compared with uncoated control. Compared with the control, loss of firmness and ascorbic acid during storage was prevented by all of the coatings except the zein coating with 20% mustard oil which enhanced softening. Color was not consistently affected by any of the coating treatments during 21 days of storage at 10°C. The results suggest that the zein-based coating containing cinnamon oil might be used to enhance microbial safety and quality of tomato.
authors.affiliation: Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, China; Tianjin Gasin-Donghui Preservation Technologies Co., Ltd., Tianjin 300457, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Yun
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 E. Mermaid Lane, Wyndmoor, PA 19038, USA. Electronic address: xuetong.fan@ars.usda.gov.
authors.forename: Xuetong
authors.initials: X
authors.lastname: Fan
authors.affiliation: Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, China.
authors.forename: Xihong
authors.initials: X
authors.lastname: Li
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 E. Mermaid Lane, Wyndmoor, PA 19038, USA.
authors.forename: Tony Z
authors.initials: TZ
authors.lastname: Jin
authors.affiliation: Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Jia
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Tree Fruit Research Laboratory, Wenatchee, WA 90081, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Mattheis
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology; D002935:Cinnamomum zeylanicum / Q000737:chemistry; D015169:Colony Count, Microbial; D005516:Food Microbiology / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D005638:Fruit / Q000382:microbiology* / Q000592:standards; D018551:Solanum lycopersicum / Q000382:microbiology*; D050296:Microbial Viability; D009149:Mustard Plant; D009822:Oils, Volatile / Q000494:pharmacology; D010938:Plant Oils / Q000494:pharmacology; D012486:Salmonella typhimurium / Q000187:drug effects / Q000254:growth & development*; D015028:Zein / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D009822:Oils, Volatile; D010938:Plant Oils; D015028:Zein; C027793:mustard oil
keywords: Color; Essential oil; Firmness; SEM; Salmonella; Zein