Microbiological Quality of Fresh Produce and Ready-to-Eat Salads Through the Processing Line at a Mass Catering System

Abstract

This study investigated the microbiological load of vegetables used for salad preparation through the salad processing line of a mass catering establishment and salad as a final product. Total viable count (TVC), the levels of total coliform bacteria and Staphylococcus aureus (S. aureus), and the presence of Eschericia coli (E. coli) in the salads a long with the processing line were determined. A total of 510 vegetable and salad samples, and 30 washing water samples (before and after washing) were collected and analyzed. The results showed that the TVCs were ranging between 5.54 log cfu/g and 6.66 log cfu/g on the fresh produce entering kitchen. The total coliform bacteria levels were between 3.31 log cfu/g and 5.98 log cfu/g. The levels of S. aureus obtained from vegetables just before processing were between 2.10 log cfu/g and 4.91 log cfu/g. The incidence of E. coli was ranging between 10 and 30%. In salads, the levels for TVC, total coliform bacteria and S. aureus were 5.36 log cfu/g, 4.72 log cfu/g and 2.67 log cfu/g, respectively. The incidence of E. coli was 30%. The levels of bacteria examined and the incidence of E. coli in salads were found to be substantially high and cross contamination was present through the steps of salad processing line. It is thought that the results of this study may help the establishments to reduce cross contamination at the processing steps and potential public health hazards.

Keywords

• Foodborne microorganisms
• food preservation and processing
• food safety and quality
• fresh-cut fruit and vegetables
• salad.

Toplu Tüketim Merkezlerinde Salatalık Sebzelerin ve Tüketime Hazır Salataların Üretim Hattı Boyunca Mikrobiyolojik Kaliteleri

Öz

Bu çalışmada bir toplu tüketim işletmesi için salata hazırlama sürecinde üretim basamaklarında kullanılan sebzelerin ve son ürün olan salatanın mikrobiyolojik kalitesi araştırılmıştır. Toplam mezofil aerobik canlı sayısı (TMAC), toplam kolifom bakteri ve Staphylococcus aureus (S. aureus) seviyeleri ile hazırlama süreci boyunca üretim basamaklarındaki Eschericia coli (E. coli) varlığı tespit edilmiştir. Çalışma kapsamında toplam 510 adet sebze ve salata örneği ile 30 adet yıkama suyu örneği (yıkama öncesi ve sonrası) analiz edilmiştir. Sonuçlar mutfağa giren taze ürünlerin TMAC sayılarının 5,54 log kob/g ile 6,66 log kob/g arasında değiştiğini göstermiştir. Toplam koliform bakteri seviyeleri 3,31 log kob/g ile 5,98 log kob/g arasında bulunmuştur. İşlemeden hemen önce sebze örneklerinden elde edilen S. aureus seviyeleri 2,10 log kob/g ile 4,91 log kob/g arasında bulunmuştur. Taze sebze örneklerinde E. coli’nin bulunma oranı ise %10 ile %30 arasında belirlenmiştir. Salatalarda TMAC sayısı, toplam koliform bakteri ve S. aureus seviyeleri sırasıyla 5,36 log kob/g, 4,72 log kob/g ve 2,67 log kob/g olarak tespit edilmiştir. Salata örneklerinde E. coli bulunma oranının ise %30 olduğu gözlemlenmiştir. Araştırmada bir toplu yemek işletmesinin salata işleme hattında salatalarda incelenen bakterilerin mikrobiyolojik yükü ile E. coli varlığının oldukça yüksek olduğu ve işleme hattında çapraz kontaminasyonun mevcut olduğu bulunmuştur. Bu çalışmanın sonuçlarının, işletmelere çapraz kontaminasyonu ve olası halk sağlığı tehlikelerini azaltmada yardımcı olabileceği düşünülmektedir.

Anahtar Kelimeler

• Gıda kaynaklı mikroorganizmalar
• gıda güvenliği ve kalitesi
• gıda muhafazası ve işlenmesi
• salata
• taze kesilmiş meyve ve sebzeler

Kaynakça

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