NIR Spectroscopy for Internal and External Quality Measurement and Analysis of Thick Rind Fruits

The global horticultural industry is continually faced with new technological challenges to be more internationally competitive and to meet the growing demand for quality-assured agricultural products. To meet these challenges, a global trend in postharvest research has resulted in the development of rapid detection and prediction of external and internal product quality attributes. Among the various non-destructive technologies, near-infrared spectroscopy (NIRS) is the most cost-effective and rapid method for qualitative and quantitative analysis of a wide range of fresh and processed horticultural products. NIRS offers tremendous prospects for application in measuring and predicting the organoleptic and nutritional quality of fruits. Unlike deciduous fruit such as apples and pears with thin rind/skin/peel, thick rind fruit has been reported to interfere with the prediction of internal quality parameters by near-infrared spectroscopy, primary due to the inadequate penetration depth of NIR radiation. This chapter provides a brief overview of the application of near-infrared spectroscopy to evaluate various internal and external quality parameters of thick rind fruit, including the measurement and prediction of internal and external disorders and diseases. A brief overview of the role of spectral acquisition, wavelength selection, chemometrics, and preprocessing techniques play in the model development of thick rind fruit. Finally, the prospects of NIRS technology in evaluating the quality attributes of fruits with thick rind are highlighted.