, the best spectra pretreatment were determined by comparing the performance of two fold-group repeated cross-validation (2 random groups of 30 samples selected at random, repeated 50 times) [6] . Model results for TS content and for CP content ( table 3 & 4 ), for the best spectra pretreatment (among SNV, derivatives, normalization) were evaluated on the basis of the coefficient of determination (R ² cv ) and the root mean square standard error of cross-validation

, CRediT author statement Abdallah Zgouz: conceptualization, methodology, investigation, data curation, validation, writing -original draft; Daphné Héran: conceptualization, investigation, methodology

, Laurent Bonnal: resources; Vincent Baeten: methodology, validation; writing-reviewing and editing

M. Bonin and ;. Roger, software, writing-reviewing and editing, validation; Ryad Bendoula: funding acquisition, conceptualization, supervision, methodology, validation, writing -review & editing, investigation; Gilles Chaix: project administration, funding acquisition, conceptualization, investigation; methodology, data curation, supervision, validation, writing -original draft

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