Impact of shortwave ultraviolet (UV-C) radiation on the antioxidant activity of thyme (Thymus vulgaris L.)

Dogu-Baykut E., Güneş G., DECKER E. A.

FOOD CHEMISTRY, cilt.157, ss.167-173, 2014 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 157
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1016/j.foodchem.2014.02.027
  • Dergi Adı: FOOD CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.167-173
  • Anahtar Kelimeler: Thyme, Shortwave ultraviolet, Antioxidant activity, Oxidation, Corn oil-in-water emulsion, MICROBIAL DECONTAMINATION, ROSEMARY EXTRACTS, GAMMA-IRRADIATION, SUNFLOWER OIL, PULSED-LIGHT, SAGE, INACTIVATION, OFFICINALIS, OXIDATION, SPICES
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

Thyme is a good source of antioxidant compounds but it can be contaminated by microorganisms. An experimental fluid bed ultraviolet (UV) reactor was designed for microbial decontamination of thyme samples and the effect of shortwave ultraviolet light (UV-C) radiation on antioxidant properties of thyme was studied. Samples were exposed to UV-C radiation for 16 or 64 min. UV-C treatment led to 1.04 and 1.38 log CFU/g reduction of total aerobic mesophilic bacteria (TAMB) counts. Hunter a* value was the most sensitive colour parameter during UV-C treatment. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of extracts was not significantly affected by UV-C. Addition of thyme extracts at 0.15 and 0.3 mu mol GAE/ml emulsion delayed the formation of lipid hydroperoxides and headspace hexanal in the 5.0% (wt) corn oil-in-water emulsion from 4 to 9 and 14 days, respectively. No significant changes in oxidation rates were observed between UV-C treated and untreated samples at same concentrations. (C) 2014 Elsevier Ltd. All rights reserved.