Determination of soluble solid content and acidity of loquats based on FT-NIR spectroscopy

作     者：Xia-ping FU Jian-ping LI Ying ZHOU Yi-bin YING Li-juan XIE Xiao-ying NIU Zhan-ke YAN Hai-yan YU 

作者机构：College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 China 

出 版 物：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 (浙江大学学报（英文版）B辑（生物医学与生物技术）)

年 卷 期：2009年第10卷第2期

页      面：120-125页

核心收录：

学科分类：09[农学] 0902[农学-园艺学] 090201[农学-果树学] 

基　　金：Project supported by the National Natural Science Foundation of China(No.30825027) the National Key Technology R&D Program of China(No.2006BAD11A12) 

主　　题：Near infrared (NIR) spectroscopy Loquats Soluble solid content (SSC) Acidity Partial least square (PLS) Modeling Spectra preprocessing 

摘      要：The near infrared （NIR） spectroscopy technique has been applied in many fields because of its advantages of simple preparation, fast response, and non-destructiveness. We investigated the potential of NIR spectroscopy in diffuse reflectance mode for determining the soluble solid content （SSC） and acidity （pH） of intact loquats. Two cultivars of loquats （Dahongpao and Jiajiaozhong） harvested from two orchards （Tangxi and Chun＇an, Zhejiang, China） were used for the measurement of NIR spectra between 800 and 2500 nm. A total of 400 loquats （100 samples of each cultivar from each orchard） were used in this study. Relationships between NIR spectra and SSC and acidity of loquats were evaluated using partial least square （PLS） method. Spectra preprocessing options included the first and second derivatives, multiple scatter correction （MSC）, and the standard normal variate （SNV）. Three separate spectral windows identified as full NIR （800-2500 nm）, short NIR （800-1100 rim）, and long NIR （1100-2500 nm） were studied in factorial combination with the preprocessing options. The models gave relatively good predictions of the SSC of loquats, with root mean square error of prediction （RMSEP） values of 1.21, 1.00, 0.965, and 1.16 °Brix for Tangxi-Dahongpao, Tangxi-Jiajiaozhong, Chun＇an-Dahongpao, and Chun＇an-Jiajiaozhong, respectively. The acidity prediction was not satisfactory, with the RMSEP of 0.382, 0.194, 0.388, and 0.361 for the above four loquats, respectively. The results indicate that NIR diffuse reflectance spectroscopy can be used to predict the SSC and acidity of loquat fruit.