Comparison of effects of mild heat combined with lactic acid on Shiga toxin producing Escherichia coli O157:H7, O103, O111, O145 and O26 inoculated to spinach and soybean sprout


DİKİCİ A., Koluman A., Calicioglu M.

Food Control, cilt.50, ss.184-189, 2015 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 50
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.foodcont.2014.08.038
  • Dergi Adı: Food Control
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.184-189
  • Anahtar Kelimeler: Decontamination, E. coli O157:H7, Fresh produce, Mild heat, Non-O157 Shiga toxin-producing E. coli, Organic acids
  • Uşak Üniversitesi Adresli: Evet

Özet

The aim of the present study was to investigate the effect of lactic acid against Shiga toxin producing Escherichia coli (O157:H7 and non-O157 serogroups including O103, O111, O145 and O26) at different conditions. Soybean sprouts and spinach leaves inoculated with each serogroup of E. coli (~7.00 + 1.00 log10 cfu/g) were treated with the lactic acid solutions at different concentrations (0% (control), 1.5%, 2.0%, or 2.5%) and at different temperatures (20, 40, or 50 °C) for 3 min. Results indicated that regardless of the treatment temperature, no significant reduction in the numbers of any serogroup occurred in the control group (0%) (p > 0.05). However, lactic acid at concentration of 1.5%, 2% and 2.5% was found to be effective against all organisms tested. There was no significant difference (p > 0.05) between E. coli O157:H7 and non-O157 STEC serogroups at any treatment group. The highest reductions (ca. 4.00 log10 cfu/g) of all serotypes in both produces were observed after immersing into 2.5% lactic acid at 50 °C. The results of this study showed that decontamination of fresh produces such as spinach and soybean sprout with lactic acid solutions prepared at mild temperatures (40 °C and 50 °C) might be an effective safety measure in preventing public health risks associated with these products contaminated with STEC.