Determination of Lead and Cadmium Elements in Milk Chocolate with ICP-OES and Method Validation Study

Abstract

In this study, a method validation study was performed for the determination of lead (Pb), cadmium (Cd) elements in chocolate by inductively coupled plasma optical emission spectrometry (ICP-OES). As the validation parameters, determination limit (LOD), measurement limit (LOQ), linear measurement range, sensitivity and precision were determined. Certified Reference Materials (CRM) were used in the study. Repeatability was in the range of 0,0365-1,197 ppm for Pb, 0,064-0,247 ppm for Cd, accuracy between 0,365-1,255 and 0,065-0,247 ppm, respectively. Recovery rates were determined as 71,51-96,56% and 64,10-88,05%. In the study, 20 milk chocolate samples were examined, Pb and Cd concentrations were determined between 0,004-0,009 and 0,001-0,002 ppm, respectively, and LOD and LOQ values were calculated as 0,005 and 0,016 for Pb, 0,001 and 0,002 for Cd. The results obtained, Eurachem “The Fitness for Purpose of Analytical Methods” Second Edition 2014 and NMKL 161 method and Turkish Food Codex “Lead, cadmium, mercury, inorganic tin, 3-MCPD, 2 diol and polycyclic aromatic hydrocarbon levels in foods sampling, sample preparation and analysis method criteria were found to be appropriate for the control according to the communique (Communique No: 2014/2).

Keywords

• Chocolate
• Cadmium
• Lead
• Cocoa
• Validation
• ICP-OES

Sütlü Çikolatalarda Kurşun ve Kadmiyum Elementlerinin ICP-OES ile Tespiti ve Metod Validasyon Çalışması

Öz

Bu çalışmada, indüktif olarak eşleşmiş plazma optik emisyon spektrometresi (ICP-OES) ile çikolatada kurşun (Pb), kadmiyum (Cd) elementlerin tespiti için metod validasyon çalışması yapılmıştır. Validasyon parametreleri olarak, tayin limiti (LOD), ölçüm limiti (LOQ), lineer ölçüm aralığı, hassasiyet ve kesinlik belirlenmiştir. Çalışmada, Sertifikalı Referans Materyalleri (CRM) kullanılmıştır. Tekrarlanabilirlik, Pb için 0.0365-1.197 ppm, Cd için 0.064-0.247 ppm, doğruluk sırasıyla 0.365-1.255 ve 0.065-0.247 ppm aralığında idi. Geri kazanım oranları ise %71.51-96.56 ve %64.10-88.05 olarak belirlenmiştir. Çalışmada 20 sütlü çikolata örnekleri incelenmiş olup, Pb ve Cd konsantrasyonları sırasıyla 0.004-0.009 ve 0.001-0.002 ppm aralığında tespit edilmiş olup LOD ve LOQ değerleri Pb için 0.005 ve 0.016, Cd için 0.001 ve 0.002 olarak hesaplanmıştır. Elde edilen sonuçların, Eurachem “ The fitness for purpose of Analytical Methods” Second Edition 2014’e ve NMKL 161 metodu ve Türk Gıda Kodeksi “Gıdalarda kurşun, kadmiyum, cıva, inorganik kalay, 3-MCPD, 2 diol ve polisiklik aromatik hidrokarbon seviyelerinin resmi kontrolü için numune alma, numune hazırlama ve analiz metodu kriterleri tebliğine (Tebliğ No: 2014/2) göre uygun olduğu görülmüştür.

Anahtar Kelimeler

• Çikolata
• kadmiyum
• kurşun
• kakao
• validasyon

Kaynakça

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