Soluble solids content and pH prediction and varieties discrimination of grapes based on visible-near infrared spectroscopy

Visible and near infrared reflectance spectroscopy was used for the non-destructive variety discrimination and the prediction of soluble solids content (SSC) and pH of grapes. Spectra of 439 grape samples from three varieties were analyzed by genetic algorithm (GA). Results of GA indicated the most effective wavelengths for the variety discrimination and content prediction. With the spectra of the effective wavelengths from GA, variety discrimination and component content prediction were executed based on least-squares support vector machine. There were 293 samples of grapes used for calibration and the left 146 samples for prediction. The correct answer rate of 96.58% for variety discrimination was achieved. The correlation coefficients are 0.9781 for pH and 0.9065 for SSC in the prediction set. Models established based on effective wavelengths overperformed those that use whole spectral data.

[1]  B. Nicolai,et al.  NON-DESTRUCTIVE MEASUREMENT OF ACIDITY, SOLUBLE SOLIDS, AND FIRMNESS OF JONAGOLD APPLES USING NIR-SPECTROSCOPY , 1998 .

[2]  C. B. Lucasius,et al.  Genetic algorithms for large-scale optimization in chemometrics: An application , 1991 .

[3]  Yong He,et al.  [Discrimination of varieties of apple using near infrared spectra based on principal component analysis and artificial neural network model]. , 2006, Guang pu xue yu guang pu fen xi = Guang pu.

[4]  Silvia Arazuri,et al.  Maturity, Variety and Origin Determination in White Grapes (Vitis Vinifera L.) Using near Infrared Reflectance Technology , 2005 .

[5]  Shyam Narayan Jha,et al.  Non‐destructive determination of acid–brix ratio of tomato juice using near infrared spectroscopy , 2004 .

[6]  Di Wu,et al.  Study on infrared spectroscopy technique for fast measurement of protein content in milk powder based on LS-SVM , 2008 .

[7]  V. Mcglone,et al.  Vis/NIR estimation at harvest of pre- and post-storage quality indices for 'Royal Gala' apple , 2002 .

[8]  D. Slaughter,et al.  Nondestructive Determination of Soluble Solids in Tomatoes using Near Infrared Spectroscopy , 1996 .

[9]  M. M. Ferreira,et al.  Nondestructive determination of solids and carotenoids in tomato products by near-infrared spectroscopy and multivariate calibration. , 2005, Analytical chemistry.

[10]  J. Abbott,et al.  NEAR-INFRARED DIFFUSE REFLECTANCE FOR QUANTITATIVE AND QUALITATIVE MEASUREMENT OF SOLUBLE SOLIDS AND FIRMNESS OF DELICIOUS AND GALA APPLES , 2003 .

[11]  Stanley J. Kays,et al.  Near-infrared (NIR) Spectrometric Technique for Nondestructive Determination of Soluble Solids Content in Processing Tomatoes , 1998 .

[12]  Johan A. K. Suykens,et al.  Least Squares Support Vector Machines , 2002 .

[13]  C. Pizarro,et al.  Coffee varietal differentiation based on near infrared spectroscopy. , 2007, Talanta.

[14]  J. Roger,et al.  Application of LS-SVM to non-linear phenomena in NIR spectroscopy: development of a robust and portable sensor for acidity prediction in grapes , 2004 .