Combined effects of gamma-irradiation and modified atmosphere packaging on quality of some spices

Food Chem. 2014 Jul 1:154:255-61. doi: 10.1016/j.foodchem.2014.01.002. Epub 2014 Jan 10.

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.

Keywords: Essential oil; Gamma-irradiation; Modified atmosphere packaging; Spice quality; Spices.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cuminum / chemistry
  • Cuminum / microbiology
  • Cuminum / radiation effects*
  • Food Irradiation / methods*
  • Food Packaging
  • Gamma Rays
  • Piper nigrum / chemistry
  • Piper nigrum / microbiology
  • Piper nigrum / radiation effects*
  • Quality Control
  • Rosmarinus / chemistry
  • Rosmarinus / microbiology
  • Rosmarinus / radiation effects*
  • Spices / analysis*
  • Spices / microbiology
  • Spices / radiation effects*
  • Thymus Plant / chemistry
  • Thymus Plant / microbiology
  • Thymus Plant / radiation effects*