VWR Kromojenik Koliform Agar ve Biokar Compass ECC Agar'ın Çeşitli Gıda Matrislerindeki İşlevselliğinin Kabul Görmüş ISO 4832 ve TEMPO TC Yöntemleriyle Birlikte Değerlendirilmesi ve TEMPO TC'nin Laboratuvar İçi Validasyonunun Uygulanması

Abstract

Koliform bakteriler genellikle gıda hijyeni ve sanitasyon koşullarının göstergesi olarak gösterilse de varlıkları mutlaka patojenite anlamına gelmez. ISO 4832:2006 yöntemi, koliform sayımında kullanılan dünya çapında kabul görmüş uluslararası bir standarttır, ancak yoğun emek ve zaman gerektirir. Kromojenik besiyerleri ve TEMPO TC gibi otomatik MPN sistemleri daha hızlı alternatifler olarak mevcut olsa da farklı gıda matrisleri arasında karşılaştırmalı çalışmalar hala sınırlıdır. Bu çalışmada, ISO 4832, TEMPO TC ve iki kromojenik agar (VWR Kromojenik Koliform Agar ve Biokar Compass ECC Agar), yüksek, orta ve düşük kontaminasyon seviyelerinde E.coli NCTC 12923 ile yapay olarak aşılanmış süt, tavuk ve unda koliform sayımı için karşılaştırılmıştır. Sayımlar paralel olarak elde edilmiş ve Pearson korelasyon ve regresyon analizi ile analiz edilmiştir. TEMPO TC'nin laboratuvar içi validasyonu, pastörize sütte ISO 16140-3:2021 standardına uygun olarak gerçekleştirilmiştir. TEMPO TC ile ISO 4832 (R² = 0.83-0.85), TEMPO TC ile kromojenik agarlar (R² = 0.82-0.84) ve ISO 4832 ile kromojenik agarlar (R² = 0.85-0.89) arasında güçlü korelasyonlar tespit edilmiştir. TEMPO TC'nin validasyonu, ISO 16140-3 kriterlerini karşılayan tekrarlanabilirliği (SIR = 0.203) bulunarak doğrulandı. Bulgularımız, kromojenik agarların ve TEMPO TC'nin ISO 4832'ye güvenilir alternatif yöntemler olarak hizmet edebileceğini ve TEMPO TC'nin daha hızlı işleme, otomasyon ve tekrarlanabilirlik gibi ek avantajlar sağladığını göstermektedir.

Keywords

• Toplam koliform sayımı
• TEMPO TC (Toplam koliformlar)
• ISO 4832
• kromojenik agar
• laboratuvar içi doğrulama
• gıda güvenliği

Evaluation of the Functionality of VWR Chromogenic Coliforms Agar and Biokar Compass ECC Agar in Various Food Matrices in Combination with Accepted ISO 4832 and TEMPO TC Methods and Implementation of In-laboratory Validation of TEMPO TC

Abstract

Coliform bacteria are generally shown as indicators of food hygiene and sanitary conditions; although, their presence does not necessarily imply pathogenicity. The ISO 4832:2006 method is a globally accepted standard used in coliform counting but it is labor-intensive and time-consuming. Faster alternatives, such as chromogenic media and automated MPN systems like TEMPO TC, exist; though, comparative studies across different food matrices are still limited. In this study, ISO 4832, TEMPO TC, and two chromogenic agars (VWR Chromogenic Coliforms Agar and Biokar Compass ECC Agar) were compared for coliform enumeration in milk, chicken, and flour artificially inoculated with E.coli NCTC 12923 at high, moderate, and low contamination levels. Counts were obtained in parallel and analyzed by Pearson correlation and regression analysis. Intralaboratory validation of TEMPO TC was performed in pasteurized milk in accordance with ISO 16140-3:2021. Strong correlations were detected between TEMPO TC and ISO 4832 (R² = 0.83-0.85), TEMPO TC and chromogenic agars (R² = 0.82-0.84), and ISO 4832 and chromogenic agars (R² = 0.85-0.89). Validation of TEMPO TC confirmed reproducibility (SIR = 0.203), satisfying ISO 16140-3 criteria. Our findings demonstrate that chromogenic agars and TEMPO TC can serve as reliable alternative methods to ISO 4832 and TEMPO TC provides additional advantages such as faster processing, automation, and reproducibility.

Keywords

• Total coliform enumeration
• TEMPO TC (Total coliforms)
• ISO 4832
• chromogenic agar
• intralaboratory validation
• food safety

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