Surface decontamination of white cheese by pulsed UV light treatment

KEKLİK N. M. , ELİK A. , SALGIN U. , Demirci A., Kocer G.

JOURNAL OF FOOD SAFETY AND FOOD QUALITY-ARCHIV FUR LEBENSMITTELHYGIENE, cilt.71, sa.4, ss.86-92, 2020 (SCI İndekslerine Giren Dergi) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 71 Konu: 4
  • Basım Tarihi: 2020
  • Doi Numarası: 10.2376/0003-925x-71-86
  • Sayfa Sayıları: ss.86-92


Surface contamination of cheese varieties with pathogenic microorganisms is a potential risk in dairy industry. Pulsed UV (PUV) light is a method, which provides rapid inactivation of a wide range of microorganisms on foods. In this study, white cheese inoculated on top surface with Staphylococcus aureus or Escherichia coli O157:H7 was exposed to PUV light. Treatment parameters were time (5, 15, 30, 45, 60 s) and distance from the quartz window of xenon lamp (5, 8, 13 cm). The 60 s-8 cm treatment (91.22 J/cm(2)) resulted in the highest inactivation level without visually altering the appearance of white cheese. After this treatment, approximately 1.31 and 2.20 log(10) reductions (cfu/cm(2)) were obtained for S. aureus and E. coli 0157:H7, respectively. Lipid oxidation, pH, and moisture content, except the color parameters, remained unchanged (p>0.05) after the 60 s-8 cm treatment. Only 1.75 % of the PUV light reached to a depth of 0.5 cm in white cheese after treatment at 5 cm. These findings indicate that although PUV light is able to reduce pathogen counts of white cheese, this technology can only be utilized for surface decontamination.