Ufuk BAĞCI, Sine Özmen TOĞAY, Ayhan TEMİZ

Efficacy of different decontamination treatments on microbial population of leafy vegetables

Bu çalışmada, Ankara’daki yerel pazarlardan toplanan bazı yapraklı sebzelerin mikrobiyel kontaminasyon düzeyleri belirlenmiştir. Çeşitli yüzey dekontaminasyon işlemlerinin bu sebzeler üzerindeki etkileri de ayrıca incelenmiştir. Ortalama toplam mezofilik aerobik bakteri (MB) ve toplam koliform (TC) sayıları sırasıyla 6.20 - 7.14 log kob/g ve 3.39 - 4.91 log EMS/g düzeyinde bulunmuştur. İncelenen 16 örneğin 13’ünde Escherichia coli tespit edilmiştir. Çeşme suyuna daldırma işlemi, sebzelerdeki mikrobiyel popülasyonun azaltılmasında etkili bulunmamıştır. MB ve TC sayılarındaki azalma açısından klor (200 mg/L) ve asetik asit (% 0.25, v/v) ile yıkama işlemleri arasında istatistiksel olarak önemli bir fark bulunmamıştır. MB ve TC sayılarındaki en fazla azalma, birbirini takip eden asetik asit ve klor uygulamasıyla elde edilmiştir. Bu sonuçlara göre de asetik asitin gıda işletmelerinde ve ev düzeyinde yapraklı sebzelerin yüzey dekontaminasyon uygulamalarında klora alternatif olabileceği ortaya çıkmıştır. Mikrobiyel dekontaminasyon düzeyi farklı sanitizerlerin ardışık uygulamaları ile arttırılabilecektir.

Değişik dekontaminasyon yöntemlerinin yapraklı sebzelerde mikrobiyel yük üzerine etkisi

In the present study, levels of microbial contamination on some leafy vegetables collected from local wholesale markets (Ankara, Turkey) were determined. The efficacies of different surface decontamination methods on these vegetables were also investigated. Average total mesophilic aerobic bacteria (MB) and total coliform (TC) counts were between 6.20 - 7.14 log cfu/g, and 3.39 - 4.91 log MPN/g, respectively. Of the sixteen samples analyzed, thirteen contained Escherichia coli. Dipping in tap water was not effective at reducing microbial populations on vegetables. Difference between chlorine (200 mg/L) and acetic acid (0.25 %, v/v) treatments in the reduction of MB and TC counts was found to be statistically insignificant. The highest reduction in both MB and TC counts was obtained by sequential treatment with acetic acid followed by chlorine. According to these results, acetic acid can be an alternative to chlorine for surface decontamination of leafy vegetables in food establishments and house level. Level of microbial decontamination can be increased by sequential dipping in different sanitizers.

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