Moisture Determination of Copra by Near Infrared Spectroscopy
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摘要:
目的 利用近红外光谱技术建立成熟椰果中椰子肉水分含量的近红外定量检测模型,实现椰子品种椰干含量及椰子种质含水率的高效率实时在线检测,满足椰干产量预测及椰子种质快速鉴定的需求。 方法 采用国产光栅S400型近红外农产品品质测定仪,对来自不同种质的360个成熟椰果的椰肉样本进行近红外光谱扫描,将采集到的光谱,以建模集∶检验集为1∶1的比例进行样本集划分,利用定量偏最小二乘分析方法建立椰肉含水率定量模型,同时分析一阶导数、二阶导数、散射校正、中心化、极差归一法等预处理方法对定量模型性能的影响。 结果 椰肉样本的近红外原始光谱所建模型性能最佳,其含水率检测模型建模集和检验集的相关系数分别为0.9963和0.9960,校正标准差和预测标准差分别为0.7605和0.8378。 结论 试验所建立的椰肉含水率近红外定量检测模型可以实现椰肉含水率的快速检测,满足椰子种质椰干产量的高通量鉴定和实际生产需求,对椰肉蛋白质、脂肪、糖类含量的快速检测有重要借鉴意义。 Abstract:Objective A high-efficiency, real-time, inline assay using near infrared spectroscopy to determine the moisture content in coconut meat was developed. Method The near infrared (NIR) spectra of 360 mature copra specimens came from varied germplasms were scanned by a grating diffuse NIR instrument made in China (S400 NIR Spectrophotometer for Quality of Agricultural Products). The collected data were separated by half into modeling and test sets. The quantitative partial least squares analysis was applied for the model construction with data pretreatments, such as first derivative, second derivative, scatter correction, zero-centered, and range normalization. Result The developed models achieved optimal performance. The root mean square error of calibration (SEC) and that of prediction (SEP) on the models were 0.7605 and 0.8378, respectively, while the correlation coefficients on the modeling and test sets 0.9963 and 0.9960, respectively. Conclusion The newly developed method for the determination of copra moisture content was capable of instantly and precisely delivering the measurement. It could be employed for real-time detection on a coconut processing line for quality assurance and yield prediction. Moreover, similar approach could conceivably be used to develop protein, fat, and carbohydrate determinations for copra as well. -
Key words:
- near infrared spectroscopy /
- moisture content /
- copra
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表 1 椰肉水分检测QPLS模型结果
Table 1. NIR-spectrum-based copra moisture determination obtained by using QPLS models
预处理方法
Pretreatment method建模集
Modeling set检验集
Test set相关系数
R校正标准差
SEC相关系数
R预测标准差
SEP原始光谱
Original spectra0.9963 0.7605 0.9960 0.8378 一阶导数
First derivative0.9865 1.4576 0.9880 1.4557 二阶导数
Second derivative0.9947 0.9126 0.9941 1.0201 散射校正
Scatter correction0.9932 1.0364 0.9907 1.2787 中心化
Zero-centered0.9981 0.5538 0.9950 0.9310 极差归一
Range normalization0.9956 0.8318 0.9953 0.8983 -
[1] 刘立云, 李杰, 董志国. 国内外椰子育种发展状况 [J]. 中国南方果树, 2007, 36(6):48−51. doi: 10.3969/j.issn.1007-1431.2007.06.021LIU L Y, LI J, DONG Z G. Development of coconut breeding in the world [J]. South China Fruits, 2007, 36(6): 48−51.(in Chinese) doi: 10.3969/j.issn.1007-1431.2007.06.021 [2] 沈晓君, 李瑞, 邓福明, 等. 初榨椰子油在烘焙食品中的应用 [J]. 中国油脂, 2019, 44(8):147−149.SHEN X J, LI R, DENG F M, et al. Application of virgin coconut oil in baking field [J]. China Oils and Fats, 2019, 44(8): 147−149.(in Chinese) [3] DEVI A, KHATKAR B S. Effects of fatty acids composition and microstructure properties of fats and oils on textural properties of dough and cookie quality [J]. Journal of Food Science and Technology, 2018, 55(1): 321−330. doi: 10.1007/s13197-017-2942-8 [4] ALLEYNE T, ROACHE S, THOMAS C, et al. The control of hypertension by use of coconut water and mauby: Two tropical food drinks [J]. The West Indian Medical Journal, 2005, 54(1): 3−8. [5] ANURAG P, RAJAMOHAN T. Cardioprotective effect of tender coconut water in experimental myocardial infarction [J]. Plant Foods for Human Nutrition, 2003, 58(3): 1−12. [6] 郑亚军, 陈卫军. 天然椰子水的抗氧化活性 [J]. 热带作物学报, 2009, 30(2):230−233. doi: 10.3969/j.issn.1000-2561.2009.02.022ZHENG Y J, CHEN W J. Antioxidative activities of natural coconut water [J]. Chinese Journal of Tropical Crops, 2009, 30(2): 230−233.(in Chinese) doi: 10.3969/j.issn.1000-2561.2009.02.022 [7] 郑亚军, 陈卫军, 辛波. 椰子花序汁液中多糖的抗氧化活性 [J]. 热带作物学报, 2009, 30(3):392−395. doi: 10.3969/j.issn.1000-2561.2009.03.028ZHENG Y J, CHEN W J, XIN B. Antioxidant activities of polysaccharides from coconut inflorescence Sap [J]. Chinese Journal of Tropical Crops, 2009, 30(3): 392−395.(in Chinese) doi: 10.3969/j.issn.1000-2561.2009.03.028 [8] VILLARINO B J, DY L M, LIZADA M C C. Descriptive sensory evaluation of virgin coconut oil and refined, bleached and deodorized coconut oil [J]. LWT - Food Science and Technology, 2007, 40(2): 193−199. doi: 10.1016/j.lwt.2005.11.007 [9] YANG Y D, IQBAL A, QADRI R. Breeding of Coconut (Cocos Nucifera L. ): The Tree of LifeAdvances in Plant Breeding Strategies: Fruits, 2018: 673-725. DOI: 10.1007/978-3-319-91944-7_17. [10] BOURDEIX R, BATUGAL P, OLIVER J T, et al. Catalogue of conserved coconut germplasm[M]. ISBN: 978-92-9043-831-1. Rome: Bioversity International, 2010. [11] 贾永立, 赵松林. 椰干干燥技术的发展现状与分析 [J]. 江西农业学报, 2012, 24(1):120−123,127. doi: 10.3969/j.issn.1001-8581.2012.01.037JIA Y L, ZHAO S L. Current development of desiccated coconut and its processing equipment [J]. Acta Agriculturae Jiangxi, 2012, 24(1): 120−123,127.(in Chinese) doi: 10.3969/j.issn.1001-8581.2012.01.037 [12] 胡晓航, 李海洋. 近红外光谱技术在农产品品质分析中的应用 [J]. 林业科技情报, 2007, 39(1):6−8. doi: 10.3969/j.issn.1009-3303.2007.01.004HU X H, LI H Y. Applications of near infrared spectroscopy technology in analyzing the quality of agricultural products [J]. Forestry Science and Technology Information, 2007, 39(1): 6−8.(in Chinese) doi: 10.3969/j.issn.1009-3303.2007.01.004 [13] 林艳, 何紫迪, 毛积鹏, 等. 基于近红外光谱技术建立沉香含油量预测模型 [J]. 热带作物学报, 2018, 39(1):182−188. doi: 10.3969/j.issn.1000-2561.2018.01.028LIN Y, HE Z D, MAO J P, et al. Prediction models of oil content of agarwood based on near infrared spectroscopy [J]. Chinese Journal of Tropical Crops, 2018, 39(1): 182−188.(in Chinese) doi: 10.3969/j.issn.1000-2561.2018.01.028 [14] 覃统佳, 刘冬, 从彦丽, 等. 近红外光谱法测定面粉的水分、脂肪、碳水化合物和蛋白质含量 [J]. 食品工业科技, 2020, 41(12):256−263.QIN T J, LIU D, CONG Y L, et al. Determination of moisture, fat, carbohydrates and protein contents in flour by near infrared spectroscopy [J]. Science and Technology of Food Industry, 2020, 41(12): 256−263.(in Chinese) [15] 王勇生, 李洁, 王博, 等. 基于近红外光谱技术评估高粱中粗蛋白质、水分含量的研究 [J]. 动物营养学报, 2020, 32(3):1353−1361. doi: 10.3969/j.issn.1006-267x.2020.03.043WANG Y S, LI J, WANG B, et al. Research on evaluation of crude protein and moisture contents in Sorghum grain based on near-infrared spectroscopy technique [J]. Chinese Journal of Animal Nutrition, 2020, 32(3): 1353−1361.(in Chinese) doi: 10.3969/j.issn.1006-267x.2020.03.043 [16] HAZARIKA A K, CHANDA S, SABHAPONDIT S, et al. Quality assessment of fresh tea leaves by estimating total polyphenols using near infrared spectroscopy [J]. Journal of Food Science and Technology, 2018, 55(12): 4867−4876. doi: 10.1007/s13197-018-3421-6 [17] WANG H, LV D, DONG N, et al. Application of near-infrared spectroscopy for screening the potato flour content in Chinese steamed bread [J]. Food Science and Biotechnology, 2019, 28(4): 955−963. doi: 10.1007/s10068-018-00552-x [18] SUN X D, ZHU K, LIU J B. Nondestructive detection of reducing sugar of potato flours by near infrared spectroscopy and kernel partial least square algorithm [J]. Journal of Food Measurement and Characterization, 2019, 13(1): 231−237. doi: 10.1007/s11694-018-9936-8 [19] NOYPITAK S, IMSABAI W, NOKNOI W, et al. Detection of cracked shell in intact aromatic young coconut using near infrared spectroscopy and acoustic response methods [J]. Journal of Food Measurement and Characterization, 2019, 13(3): 1991−1999. doi: 10.1007/s11694-019-00119-2 [20] 王雪, 马铁民, 杨涛, 等. 基于近红外光谱的灌浆期玉米籽粒水分小样本定量分析 [J]. 农业工程学报, 2018, 34(13):203−210. doi: 10.11975/j.issn.1002-6819.2018.13.024WANG X, MA T M, YANG T, et al. Moisture quantitative analysis with small sample set of maize grain in filling stage based on near infrared spectroscopy [J]. Transactions of the Chinese Society of Agricultural Engineering, 2018, 34(13): 203−210.(in Chinese) doi: 10.11975/j.issn.1002-6819.2018.13.024 [21] 杨传得, 于洪涛, 关淑艳, 等. 近红外反射光谱技术预测花生种子含水量 [J]. 花生学报, 2012, 41(1):6−9,20. doi: 10.3969/j.issn.1002-4093.2012.01.002YANG C D, YU H T, GUAN S Y, et al. Prediction of moisture content in single peanut seed by near infrared reflectance spectroscopy [J]. Journal of Peanut Science, 2012, 41(1): 6−9,20.(in Chinese) doi: 10.3969/j.issn.1002-4093.2012.01.002 [22] 于旭峰, 李红梅, 卓伟, 等. 基于近红外光谱技术的马铃薯叶片含水率高效预测 [J]. 光学仪器, 2020, 42(4):7−13.YU X F, LI H M, ZHUO W, et al. Efficient determination of water content in potato leaves based on spectroscopy technology [J]. Optical Instruments, 2020, 42(4): 7−13.(in Chinese) [23] 曲正义, 逄世峰, 王兆森, 等. 基于近红外光谱技术的大力参含水量快速无损检测 [J]. 时珍国医国药, 2020, 31(11):2653−2655. doi: 10.3969/j.issn.1008-0805.2020.11.026QU Z Y, PANG S F, WANG Z S, et al. Rapid nondestructive testing of boiled ginseng moisture content based on near infrared spectroscopy technique [J]. Lishizhen Medicine and Materia Medica Research, 2020, 31(11): 2653−2655.(in Chinese) doi: 10.3969/j.issn.1008-0805.2020.11.026 [24] 李陈孝, 于小庭, 赵晨宇, 等. 基于微波空间驻波法的叶类蔬菜含水率无损检测 [J]. 农业工程学报, 2021, 37(11):307−314. doi: 10.11975/j.issn.1002-6819.2021.11.035LI C X, YU X T, ZHAO C Y, et al. Non-destructive detection of moisture content of leafy vegetables based on microwave free space traveling-standing wave method [J]. Transactions of the Chinese Society of Agricultural Engineering, 2021, 37(11): 307−314.(in Chinese) doi: 10.11975/j.issn.1002-6819.2021.11.035 [25] 陈文玉, 穆宏磊, 吴伟杰, 等. 利用低场核磁共振技术无损检测澳洲坚果含水率 [J]. 农业工程学报, 2020, 36(11):303−309. doi: 10.11975/j.issn.1002-6819.2020.11.036CHEN W Y, MU H L, WU W J, et al. Nondestructive measurement of moisture content of Macadamia nuts by low-field nuclear magnetic resonance [J]. Transactions of the Chinese Society of Agricultural Engineering, 2020, 36(11): 303−309.(in Chinese) doi: 10.11975/j.issn.1002-6819.2020.11.036 [26] 李红, 张凯, 陈超, 等. 基于高光谱成像技术的生菜冠层含水率检测 [J]. 农业机械学报, 2021, 52(2):211−217,274. doi: 10.6041/j.issn.1000-1298.2021.02.019LI H, ZHANG K, CHEN C, et al. Detection of moisture content in lettuce canopy based on hyperspectral imaging technique [J]. Transactions of the Chinese Society for Agricultural Machinery, 2021, 52(2): 211−217,274.(in Chinese) doi: 10.6041/j.issn.1000-1298.2021.02.019 [27] 李君, 董磊, 姜发堂, 等. 食品中水分含量测定装置的研究现状 [J]. 食品工业科技, 2019, 40(8):297−303.LI J, DONG L, JIANG F T, et al. Development of devices for measuring the moisture contents in foods [J]. Science and Technology of Food Industry, 2019, 40(8): 297−303.(in Chinese) [28] 刘洁, 李小昱, 李培武, 等. 基于近红外光谱的板栗水分检测方法 [J]. 农业工程学报, 2010, 26(2):338−341. doi: 10.3969/j.issn.1002-6819.2010.02.058LIU J, LI X Y, LI P W, et al. Determination of moisture in chestnuts using near infrared spectroscopy [J]. Transactions of the Chinese Society of Agricultural Engineering, 2010, 26(2): 338−341.(in Chinese) doi: 10.3969/j.issn.1002-6819.2010.02.058 [29] 王文霞, 马本学, 罗秀芝, 等. 近红外光谱结合变量优选和GA-ELM模型的干制哈密大枣水分含量研究 [J]. 光谱学与光谱分析, 2020, 40(2):543−549.WANG W X, MA B X, LUO X Z, et al. Study on the moisture content of dried Hami big jujubes by near-infrared spectroscopy combined with variable preferred and GA-ELM model [J]. Spectroscopy and Spectral Analysis, 2020, 40(2): 543−549.(in Chinese) [30] 高升, 王巧华. 基于可见/近红外透射光谱技术的红提糖度和含水率无损检测 [J]. 中国光学, 2021, 14(3):566−577. doi: 10.37188/CO.2020-0085GAO S, WANG Q H. Non-destructive testing of red globe grape sugar content and moisture content based on visible/near infrared spectroscopy transmission technology [J]. Chinese Optics, 2021, 14(3): 566−577.(in Chinese) doi: 10.37188/CO.2020-0085