Analysis of beef meatballs with rat meat adulteration using Fourier Transform Infrared (FTIR) spectroscopy in combination with chemometrics

Indonesia is a country with a majority Muslim population, and the halal food consumed should be assured. One type of food that must be considered halal is food from meat products. Due to the price difference between halal meat and non-halal meat, some unethical producers try to adulterate beef with non-halal meat of rat meat. The research objective was to employ FTIR spectroscopy in combination with chemometrics for the analysis of rat meat adulteration in beef meatballs. Lipid components in meatballs containing beef, rat meat, or its binary mixture were extracted using three extraction methods, namely Bligh and Dyer, Folch, and Soxhlet methods. The lipid components extracted were then analyzed using FTIR spectroscopy and FTIR spectra obtained were used as variables during chemometrics modeling. The absorbance values of FTIR spectra of lipid components extracted by Bligh and Dyer, Folch, and Soxhlet methods at selected wavenumbers regions of 3100–800 cm−1 were selected for discrimination between beef meatballs and meatballs adulterated with rat meat using chemometrics of linear discriminant analysis (LDA). LDA was successfully used to classify lipid components extracted by three lipid extraction methods from beef meatballs and rat meatballs with accuracy levels of 100%. The prediction of rat meatballs was successfully determined using multivariate calibrations of Partial Least Square (PLS) and Principle Component Regression (PCR) using optimized conditions. The difference in lipid composition, as indicated in FTIR spectra profiles of the analyzed samples, is used as a fingerprint technique for the analysis of rat meat in beef meatballs for halal authentication purposes.