Article pubs.acs.org/ac
Determination of the Composition in Sugars and Organic Acids in Peach Using Mid Infrared Spectroscopy: Comparison of Prediction Results According to Data Sets and Different Reference Methods Sylvie Bureau,*,†,‡ Bénédicte Quilot-Turion,§ Véronique Signoret,§ Christel Renaud,∥ Mickael Maucourt,⊥,# Doriane Bancel,¶ and Catherine M. G. C. Renard†,‡ †
INRA, UMR408 Sécurité et Qualité des Produits d’Origine Végétale, Domaine Saint Paul, 228 route de l’Aérodrome, CS 40509, F-84000 Avignon, France ‡ Université d’Avignon et des Pays de Vaucluse, UMR408 Sécurité et Qualité des Produits d’Origine Végétale, F-84000 Avignon, France § INRA, UR1052 Génétique et d’Amélioration des Fruits et Légumes, Domaine Saint Maurice, Allée des Chênes, CS 60094, F-84143 Montfavet cedex, France ∥ INRA, UR419 Espèces Fruitières, Centre de Bordeaux, F-33140 Villenave d’Ornon, France ⊥ Université de Bordeaux, UMR1332 Biologie du Fruit et Pathologie, Centre INRA de Bordeaux, F-33140 Villenave d’Ornon, France # Metabolome Facility of Bordeaux Functional Genomics Center, IBVM, Centre INRA de Bordeaux, F-33140 Villenave d’Ornon, France ¶ INRA, UR1115 Plantes et Systèmes de Cultures Horticoles, Domaine Saint Paul, 228 route de l′Aérodrome, CS 40509, F-84000 Avignon, France ABSTRACT: The prediction of internal quality properties, such as sweetness and acidity, in peach fruit by mid infrared spectroscopy is of interest for rapid determination. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was tested here on two populations of peach fruits issued from contrasting genitors providing a large phenotypic variability. Over two successive years, 284 samples in 2006 and 483 samples in 2007 were characterized for soluble solids content (SSC), titratable acidity (TA), glucose, fructose, sucrose, malic acid, and citric acid contents. Sugar and organic acid composition were determined by three methods: colorimetric enzymatic measurements (ENZ), high-performance liquid chromatography (HPLC), or proton NMR spectroscopy (1H NMR), depending on the samples. For all samples, fruit homogenates were analyzed in ATR-FTIR using the same methodology and the same spectrometer. The objective here was to evaluate the effect of reference methods on the prediction performance. The best results were generally observed for SSC and TA, the percentage of the root-mean-square error of cross validation (RMSECV%) ranging respectively between 5.8% and 8.7% and between 5.9% and 8.0%, depending on the samples. For individual sugars and organic acids, the best correlations were obtained between ATR-FTIR data and ENZ reference data followed by HPLC and 1H NMR ones.
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pineapple, tomato).1−11 At an industrial level, some applications have been developed, for example, in wine production.12 To our knowledge and despite the interest of their potential applications, no study was conducted on peach fruit using ATRFTIR. Peach fruit present a large diversity of acid and sugar content. Malic and citric acids are the most abundant organic acids with concentrations ranging from 3 to 6 g/kg FW for malic acid and between 1 to 3 g/kg FW for citric acid.13 Moreover, quinic acid and succinic acid are often present in peach at low
evelopment of high through-put analyses, for example, by infrared spectroscopy, could be highly beneficial for plant scientists and professional grower applications. Indeed techniques based on infrared spectroscopy offer the advantages of requiring minimal sample preparation with a rapid and simple data acquisition. However, they demand the creation of a database with spectra and reference measurements using classical techniques and the establishment of mathematical models to predict the measured quality traits. Mid infrared spectroscopy (ATR-FTIR) relevant for analyzing homogeneous plant materials such as liquids, purees or slurries, has been used since the mid-1990s. Different applications have been described in various plant products, such as cane juices, wine extracts, fruit juices, or homogenates (apple, apricot, blueberry, © XXXX American Chemical Society
Received: July 11, 2013 Accepted: November 7, 2013
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dx.doi.org/10.1021/ac402428s | Anal. Chem. XXXX, XXX, XXX−XXX
Analytical Chemistry
Article
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