A Colorimetric Sensor Approach for Accurate Meat and Fish Freshness Monitoring

Abstract

Monitoring the freshness of meat and fish is crucial for enhancing food safety for consumers and protecting public health. In this study, a paper sensor using bromothymol blue indicator sensitive to colour change was developed. The sensor performance was compared in solutions prepared with different dye amounts and different holding times. Studies were conducted on meat and fish, and colour changes were analysedanalyzed using both RGB and ΔE values. In the first sensors produced on fish that had not yet come into contact with food, RGB values resembled grey-greenish tones. In spoiled samples, the colour changes to reddish tones. RGB analysis of meat transitions from beige to reddish tones in intact samples and from beige in spoiled samples. RGB is a method that provides objective results in monitoring spoilage. The findings emphasize that colour changes are not merely visual differences but can also be used as a highly effective parameter in determining product condition. Furthermore, solutions containing higher BTB showed more pronounced and rapid colour changes, particularly in response to alkaline compounds formed during spoilage. The paper sensor developed for determining the freshness of meat and fish products offers a practical, low-cost, rapid, and intuitive alternative. The study contributes to the optimization of sensor systems using pH-sensitive synthetic dyes and presents RGB, L*, a*, and b*-based data.

Keywords

• Bromothymol blue (BTB)
• Sensor
• Meat
• Fish
• Food freshness

Et ve Balık Tazeliğini Doğru İzleme İçin Kolorimetrik Sensör Yaklaşımı

Abstract

Et ve balığın tazeliğini izlemek, tüketiciler için gıda güvenliğini artırmak ve halk sağlığını korumak açısından çok önemlidir. Bu çalışmada, renk değişimine duyarlı bromotimol mavisi indikatörü kullanan bir kağıt sensör geliştirilmiştir. Sensörün performansı, farklı boya miktarları ve farklı bekletme süreleri ile hazırlanan çözeltilerde karşılaştırılmıştır. Et ve balık üzerinde çalışmalar yapılmış ve renk değişiklikleri hem RGB hem de ΔE değerleri kullanılarak analiz edilmiştir. Henüz gıda ile temas etmemiş balıklar üzerinde üretilen ilk sensörlerde, RGB değerleri gri-yeşilimsi tonlara benzemektedir. Bozulmuş numunelerde renk kırmızımsı tonlara dönüşmektedir. Etin RGB analizi, bozulmamış numunelerde bejden kırmızımsı tonlara, bozulmuş numunelerde ise bejden kırmızımsı tonlara geçiş göstermektedir. RGB, bozulmayı izlemede objektif sonuçlar sağlayan bir yöntemdir. Bulgular, renk değişikliklerinin yalnızca görsel farklılıklar olmadığını, aynı zamanda ürün durumunu belirlemede oldukça etkili bir parametre olarak da kullanılabileceğini vurgulamaktadır. Ayrıca, daha yüksek BTB içeren çözeltiler, özellikle bozulma sırasında oluşan alkali bileşiklere tepki olarak daha belirgin ve hızlı renk değişiklikleri göstermiştir. Et ve balık ürünlerinin tazeliğini belirlemek için geliştirilen kağıt sensör, pratik, düşük maliyetli, hızlı ve sezgisel bir alternatif sunmaktadır. Çalışma, pH'a duyarlı sentetik boyalar kullanan sensör sistemlerinin optimizasyonuna katkıda bulunmakta ve RGB, L*, a* ve b* tabanlı veriler sunmaktadır.

Keywords

• Bromotimol mavisi (BTB)
• Sensör
• Et
• Balık
• Gıda tazeliği

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