Non-destructive Measurement Of Soluble Solids OfApple Using Near-infrared Spectroscopy

摘要

One-hundred apples were chosen, using the method of partial least squares (PLS). Inthis study the potential of visible and near-infrared reflectance & transmission spectroscopy asnon-destructive measurement technique for measuring quality characteristics of apples isevaluated. The results of experiment are : Thirty samples are used to found model betweenreflectance spectrums and the soluble solids in apples’ surface, obtain a validation correlativecoefficient ( R ) of 0.99695, and the standard error of calibration (SEC) value is 0.0903; the otherseventy samples are used to predict, the validation R of value is 0.97642, and the standard errorof prediction (SEP) value is 0.287. Choosing forty samples from one hundred apples, thirtysamples are used to found model between reflectance spectrums and the soluble solids in apples,obtain a validation R of 0.98541, and the SEC value is 0.171; the other ten samples are used topredict, the validation R of 0.98747, and the SEP value is 0.322. So, Near-infrared Spectroscopy(NIRS) is able to reach the soluble solids in apples’ surface & apples demanded in practice.However, the same forty samples, thirty samples are used to found model between transmissionspectrums and the soluble solids in apples, obtain a validation R of 0.78690, and the SEC valueis 0.619; the other ten samples are used to predict, the validation R of 0.81326, and the SEPvalue is 1.804. The transmission results is unreasonable, the possible cause is the lowerprecision of apparatus, so, the transmission experiment is going on.