Effect of gamma radiation and storage at 4°C on the inactivation of Listeria monocytogenes,Escherichia coli and Salmonella enterica Typhimurium in Legon-18 pepper(Capsicum annuum)powder  

作　　者：Bernard Tawiah Odai Kwaku Tano-Debrah Kennedy Kwasi Addo Firibu K.Saalia Lorenzo Moses Akyeh 

机构地区：[1]Department of Nutrition and Food Science,University of Ghana,Legon,Accra [2]Radiation Technology Centre,Biotechnology and Nuclear Agriculture Research Institute,Ghana Atomic Energy Commission,Kwabenya,Accra [3]Noguchi Memorial Institute for Medical Research,University of Ghana,Legon,Accra

出　　处：《Food Quality and Safety》2019年第4期265-272,共8页食品品质与安全研究（英文版）

基　　金：the authors from the collection of data,its analysis,and interpretation.

摘　　要：Objectives:Spices are low moisture foods which have been known to be contaminated with various pathogens and sun-dried Legon-18 pepper powder is not left out.Due to its contamination with various pathogens,a study was conducted to determine the effects of gamma irradiation on the decontamination of Legon-18 pepper powder and on some quality parameters.Methods:Samples were obtained from a local farmer from the Eastern Region of Ghana.Sterility tests were carried out.The samples were inoculated with known cfu/ml of Escherichia coli,Listeria monocytogenes and Salmonella enterica Typhimurium.Samples were irradiated at 1,2,4,and 5 kilogray(kGy).Zero kilogray served as control(unirradiated).All samples were stored at 4oC for 60 days.Enumeration of the various pathogens was done in appropriate media.Some quality parameters were determined after irradiating unsterile samples at 5 kGy and 0 kGy served as control.Capsaicinoids and carotenoids were quantified using a high performance liquid chromatography.The samples were stored at 4oC for 8 weeks.Results:A dose-dependent effect on the inactivation of the pathogens was observed(P<0.05).Storage time affected the inactivation of the pathogens as well(P<0.05).Complete inactivation of the pathogens was observed at 5 kGy at day 0.Capsaicin,dihydrocapsaicin and total capsaicinoid content of the samples irradiated at 5 kGy increased at 23.64%,14.7%and 20.95%respectively as compared with the contents of the unirradiated samples.A gamma irradiation dose of 5 kGy caused losses of 8.11%,8.67%and 26.54%in capsanthin,beta carotene and beta cryptoxanthin respectively.Quality parameters measured reduced with storage(P<0.05).Conclusions:Gamma irradiation inactivated pathogens at 5 kGy.Lower doses used during the study could inactivate the pathogens but with time.All quality parameters and carotenoids quantified were affected by gamma irradiation and storage period(P<0.05).

关 键 词：CAPSAICINOIDS gamma irradiation PATHOGENS carotenoids 

分 类 号：TS2[轻工技术与工程—食品科学与工程]