Reyhan S Uysal1, Ozay Mentes Yilmaz2, Ismail H Boyaci2. 1. Department of Mechanical Engineering, Istanbul Gedik University, Istanbul, Turkey. 2. Department of Food Engineering, Hacettepe University, Ankara, Turkey.
Abstract
BACKGROUND: The use of liquid whole egg (LWE) in the food industry as a substitute for shell eggs has been on the increase lately. Since the composition of LWE can easily be changed, determination of protein, lipid, moisture and total soluble solid (TSS) contents of LWE has also gained importance. Traditional methods usually require more time and effort, and the use of toxic chemicals for sample preparation; hence more efficient techniques (faster, cheaper and more reliable) are needed. In this regard, a novel technique that determines LWE components using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy with partial least squares regression (PLS) is presented in this study. RESULTS: The actual values of LWE components were determined by applying reference methods. The accuracy of the PLS model was demonstrated by comparing the obtained predictions with the actual values of the components. High coefficients of determination values, which are 0.950, 0.992, 0.994 and 0.972, were achieved for protein, lipid, moisture, and TSS validation datasets, respectively. The error values, namely RMSEC, RMSECV and RMSEP, were obtained in the ranges 0.404-0.978, 0.57-1.82 and 0.83-1.84, respectively. CONCLUSIONS: ATR-FTIR spectroscopy coupled with chemometrics can provide a rapid and sensitive method for quality control of liquid egg composition.
BACKGROUND: The use of liquid whole egg (LWE) in the food industry as a substitute for shell eggs has been on the increase lately. Since the composition of LWE can easily be changed, determination of protein, lipid, moisture and total soluble solid (TSS) contents of LWE has also gained importance. Traditional methods usually require more time and effort, and the use of toxic chemicals for sample preparation; hence more efficient techniques (faster, cheaper and more reliable) are needed. In this regard, a novel technique that determines LWE components using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy with partial least squares regression (PLS) is presented in this study. RESULTS: The actual values of LWE components were determined by applying reference methods. The accuracy of the PLS model was demonstrated by comparing the obtained predictions with the actual values of the components. High coefficients of determination values, which are 0.950, 0.992, 0.994 and 0.972, were achieved for protein, lipid, moisture, and TSS validation datasets, respectively. The error values, namely RMSEC, RMSECV and RMSEP, were obtained in the ranges 0.404-0.978, 0.57-1.82 and 0.83-1.84, respectively. CONCLUSIONS: ATR-FTIR spectroscopy coupled with chemometrics can provide a rapid and sensitive method for quality control of liquid egg composition.