A PRELIMINARY STUDY ON WHETHER THE SOLUBLE SOLID CONTENT AND ACIDITY OF ORANGES PREDICTED BY NEAR INFRARED SPECTROSCOPY MEET THE SENSORY DEGUSTATION

摘要

Internal qualities of fruit, such as soluble solid content (SSC) and acidity, werernmostly used to reflect people’s sensory preference. Those indexes have beenrnnoninvasively measured by near infrared (NIR) spectroscopy over the past years.rnHowever, limited attentions have been given on whether the result of NIR spectroscopyrndetection can meet the sensory requirement of the consumers. In thisrnresearch, NIR measurement and the sensory test were carried out on oranges tornassay the answer. Multivariate analyses with several pretreatments were comparativelyrnemployed to calibrate a robust model on the basis of NIR spectra. Thernoptimal partial least squares model was obtained with root mean square error ofrnprediction of 0.613 for SSC, and 0.17 for acidity. The sensory test was investigatedrnby well-trained panelists to explore the sensory threshold, which had a root meanrnsquare error of deviation of 0.771 for SSC, as well as 0.203 for acidity. Resultsrnshowed that the noninvasive method of NIR usage was acceptable with fewer rootrnmean square error of prediction value than sensory threshold. This preliminaryrnstudy revealed that an accurate and fast method by NIR spectrometer coupledrnwith proper chemometric on oranges could meet the requirement of sensory taste.