title: Fruit quality evaluation using spectroscopy technology: a review.
abstract: An overview is presented with regard to applications of visible and near infrared (Vis/NIR) spectroscopy, multispectral imaging and hyperspectral imaging techniques for quality attributes measurement and variety discrimination of various fruit species, i.e., apple, orange, kiwifruit, peach, grape, strawberry, grape, jujube, banana, mango and others. Some commonly utilized chemometrics including pretreatment methods, variable selection methods, discriminant methods and calibration methods are briefly introduced. The comprehensive review of applications, which concentrates primarily on Vis/NIR spectroscopy, are arranged according to fruit species. Most of the applications are focused on variety discrimination or the measurement of soluble solids content (SSC), acidity and firmness, but also some measurements involving dry matter, vitamin C, polyphenols and pigments have been reported. The feasibility of different spectral modes, i.e., reflectance, interactance and transmittance, are discussed. Optimal variable selection methods and calibration methods for measuring different attributes of different fruit species are addressed. Special attention is paid to sample preparation and the influence of the environment. Areas where further investigation is needed and problems concerning model robustness and model transfer are identified.
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. hl_wang@zju.edu.cn.
authors.forename: Hailong
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. jypeng@zju.edu.cn.
authors.forename: Jiyu
authors.initials: J
authors.lastname: Peng
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. cqxie@zju.edu.cn.
authors.forename: Chuanqi
authors.initials: C
authors.lastname: Xie
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. ydbao@zju.edu.cn.
authors.forename: Yidan
authors.initials: Y
authors.lastname: Bao
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. yhe@zju.edu.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: He
keywords: SSC; Vis/NIR; acidity; characteristic wavelength; chemometrics; discrimination; fruit quality