In-house validation of analytical methods for the determination of NFCs in roasted coffee and cocoa

Process contaminants (NFCs) such as acrylamide, furfuryl alcohol (FFA), and hydroxymethylfurfural (HMF) have been linked to the development of adenomas, toxicity, and carcinogenicity. These NFCs are found in roasted coffee and cocoa consumed worldwide. Therefore, developing and evaluating reliable analytical methods for their determination is imperative. These methods are mainly based on chromatography, mass spectrometry, and absorbance detectors. However, information on the validation of analytical methods for determining NFCs, particularly in cocoa, is scarce, leading to uncertainty about the validity of the results. The performance parameters of the methods provide the reliability required for their intended use. Therefore, this study validated the performance parameters of Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and Liquid Chromatography coupled with a Diode Array Detector (LC-DAD) methods for determining NFC in roasted coffee and cocoa to provide reliable methods. The methods evaluated demonstrated a satisfactory fit to the linear model, with a coefficient of determination (R²) greater than 0.997. The accuracy of the methods ranged between 80 and 120%, and the precision and intermediate precision were below 9% RSD and below 16%. The reproducibility of the methods was between 0.36 and 2% in terms of HorRat. The methods were considered suitable for the determination of NFCs in high consumption matrices such as cocoa and coffee, in accordance with international guidelines of the Food and Drug Administration (FDA) and the Association of Official Analytical Chemists (AOAC). Obtaining these performance indicators for determining compounds of high interest, such as acrylamide, contributes to remedying the lack of information on the validation of methods for quantification, especially in cocoa. In addition, the importance of using salts for extract clean-up was established, which consistently and reliably eliminates interferences, allowing for greater sensitivity of the methods.