Halal authentication study of the chicken siomay with the adulteration of pork using FTIR spectroscopy combined with chemometrics

Abstract

Indonesia has a predominantly Muslim population, resulting in strong demand for halal products. Siomay, a type of dimsum originating in China, was initially made with pork but was later made with chicken to be marketed in Muslim countries. The large number of siomay produced by home industries is detrimental to Muslim consumers because the products are not halal-labeled, so their halal status is unknown. This study, thus, aims to identify chicken siomay and to analyze potential pork adulteration for halal verification using Fourier Transform Infrared (FTIR) spectroscopy coupled with chemometric techniques. The samples analyzed in this study consist of chicken siomay mixed with different concentrations of pork, which were used as training and testing sets. The animal fatty acid components in the samples were extracted using the Folch method, followed by spectral data acquisition by FTIR spectroscopy at wavenumbers of 4000-500 cm-1. The spectra results were used as chemometric modeling variables. The PCA (Principal Component Analysis) was performed to determine the most influential principal components in sample grouping, namely Dimension 1 (82.8%) and Dimension 2 (10.1%), with a wavenumber of 1744 cm-1 as the variable that contributed most to building the PCA model. Meanwhile, the PLS-DA (Partial Least Squares-Discriminant Analysis) was used to differentiate chicken fatty acids, pork fatty acids, and their binary mixture, with AUC-ROC values of 1.000, 0.9889, and 0.9630, respectively. These results indicate the quality of the discrimination model with high sensitivity and specificity.