Determination of 10‐Hydroxy‐2‐Decenoic Acid of Royal Jelly Using Near‐Infrared Spectroscopy Combined with Chemometrics

Abstract A rapid quantitative analysis model for determining the hydroxy‐2‐decenoic acid (10‐HDA) content of royal jelly based on near‐infrared spectroscopy combining with PLS has been developed. Firstly, near‐infrared spectra of 232 royal jelly samples with different 10‐HDA concentrations (0.35% to 2.44%) were be collected. Second‐order derivative processing of the spectra was carried out to construct a full‐spectrum PLS model. Secondly, GA‐PLS, CARS‐PLS, and Si‐PLS were used to select characteristic wavelengths from the second‐order derivative spectrum to construct a PLS calibration model. Finally, 58 samples were used to select the best predictive model for 10‐HDA content. The result show that the PLS model constructed after wavelength selection was significantly more accurate than the full spectrum model. The Si‐PLS algorithm performed best and the corresponding characteristic wavelength range were: 980 to 1038, 1220 to 1278, 1340 to 1398, and 1688 to 1746 nm. The prediction results were RMSEP = 0.1496% and R P = 0.9380. Hence, it is feasible to employ near‐infrared spectra to analyze 10‐HDA in royal jelly.