Near-infrared spectroscopy method for rapid proximate quantitative analysis of nutrient composition in Pacific oyster Crassostrea gigas

Glycogen, amino acids, fatty acids, and other nutrient components affect the flavor and nutritional quality of oysters. Methods based on near-infrared reflectance spectroscopy (NIRS) were developed to rapidly and proximately determine the nutrient content of the Pacific oyster Crassostrea gigas. Samples of C. gigas from 19 costal sites were freeze-dried, ground, and scanned for spectral data collection using a Fourier transform NIR spectrometer (Thermo Fisher Scientific). NIRS models of glycogen and other nutrients were established using partial least squares, multiplication scattering correction, first-order derivation, and Norris smoothing. The RC values of the glycogen, fatty acids, amino acids, and taurine NIRS models were 0.967 8, 0.931 2, 0.913 2, and 0.892 8, respectively, and the residual prediction deviation (RPD) values of these components were 3.15, 2.16, 3.11, and 1.59, respectively, indicating a high correlation between the predicted and observed values, and that the models can be used in practice. The models were used to evaluate the nutrient compositions of 1 278 oyster samples. Glycogen content was found to be positively correlated with fatty acids and negatively correlated with amino acids. The glycogen, amino acid, and taurine levels of C. gigas cultured in the subtidal and intertidal zones were also significantly different. This study suggests that C. gigas NIRS models can be a cost-effective alternative to traditional methods for the rapid and proximate analysis of various slaughter traits and may also contribute to future genetic and breeding-related studies in Pacific oysters.