Quantification and Prediction with Near Infrared Spectroscopy of Carbohydrates throughout Apple Fruit Development

Carbohydrates play a key role in apple fruit growth and development. are needed for cell division/expansion, regulate fruitlet abscission, influence maturation quality. Current methods to quantify carbohydrates labor intensive expensive. We quantified throughout growing season two cultivars evaluated the use of near infrared spectroscopy (NIR) predict carbohydrate content changes were with high performance liquid chromatography (HPLC) at five timepoints between early harvest ‘Gala’ ‘Red Delicious’ apples. NIR spectra was collected freeze-dried samples using benchtop spectrometer. Sorbitol major (~40% total carbohydrates). However, relative contribution sorbitol rapidly decreased by 59 days after full bloom (<10%). The proportion fructose increased development (40–50%). Three distinct periods development, early, mid-season, late, found over all sampling dates principal component analysis. first (PC1) second (PC2) components accounted 90% variation data, separated among date along PC1. Partial least squares regression used build models calibrating HPLC measured reflectance spectra. reliably predicted fructose, glucose, sorbitol, sucrose, starch, soluble sugars both Delicious’; r2 ranged from 0.60 0.96. These results show that can accurately estimate offers an efficient alternative or gas chromatography.