title: Combined effects of gamma-irradiation and modified atmosphere packaging on quality of some spices.
abstract: Thyme (Thymus vidgaris L.), rosemary (Rosmarinus officinalis L.), black pepper (Piper nigrum L.) and cumin (Cuminum cyminum L.) in ground form were packaged in either air or 100% N2 and γ-irradiated at 3 different irradiation levels (7kGy, 12kGy, 17kGy). Total viable bacterial count, yeast and mould count, colour, essential oil yield and essential oil composition were determined. Microbial load was not detectable after 12kGy irradiation of all samples. Irradiation resulted in significant changes in colour values of rosemary and black pepper. The discolouration of the irradiated black pepper was lower in modified atmosphere packaging (MAP) compared to air packaging. Essential oil yield of irradiated black pepper and cumin was lower in air packaging compared to MAP. Gamma-irradiation generally decreased monoterpenes and increased oxygenated compounds, but the effect was lower in MAP. Overall, spices should be irradiated under an O2-free atmosphere to minimise quality deterioration.
authors: Food Engineering Department, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Maslak 34469, Istanbul, Turkey.
authors: Celale
authors: C
authors: Kirkin
authors: Australian Centre for Research on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton, VIC 3800, Australia.
authors: Blagoj
authors: B
authors: Mitrevski
authors: Food Engineering Department, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Maslak 34469, Istanbul, Turkey.
authors: Gurbuz
authors: G
authors: Gunes
authors: Australian Centre for Research on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton, VIC 3800, Australia. Electronic address: philip.marriott@monash.edu.
authors: Philip J
authors: PJ
authors: Marriott
mesh_terms: D028527:Cuminum / Q000737:chemistry / Q000382:microbiology / Q000528:radiation effects*; D005514:Food Irradiation / Q000379:methods*; D018857:Food Packaging; D005720:Gamma Rays; D029222:Piper nigrum / Q000737:chemistry / Q000382:microbiology / Q000528:radiation effects*; D011786:Quality Control; D027542:Rosmarinus / Q000737:chemistry / Q000382:microbiology / Q000528:radiation effects*; D017365:Spices / Q000032:analysis* / Q000382:microbiology / Q000528:radiation effects*; D046930:Thymus Plant / Q000737:chemistry / Q000382:microbiology / Q000528:radiation effects*
keywords: Essential oil; Gamma-irradiation; Modified atmosphere packaging; Spice quality; Spices