{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,14]],"date-time":"2026-06-14T08:24:55Z","timestamp":1781425495492,"version":"3.54.1"},"reference-count":36,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,22]],"date-time":"2019-05-22T00:00:00Z","timestamp":1558483200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"New Developing Subject Construction Program of Guangdong Academy of Agricultural Science","award":["201802XX"],"award-info":[{"award-number":["201802XX"]}]},{"name":"Presidential Foundation of Guangdong Academy of Agricultural Science","award":["201920"],"award-info":[{"award-number":["201920"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31571561"],"award-info":[{"award-number":["31571561"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The objective of this study was to find an intelligent and fast method to detect the type, blended ratio, and mixed ratio of ancient Pu\u2019er tea, which is significant in maintaining order in the Pu\u2019er tea industry. An electronic nose (E-nose) and a visible near infrared spectrometer (VIS\/NIR spectrometer) were applied for tea sampling. Feature extraction was conducted using both the traditional method and a convolutional neural network (CNN) technique. Linear discriminant analysis (LDA) and partial least square regression (PLSR) were applied for pattern recognition. After sampling while using the traditional method, the analysis of variance (ANOVA) results showed that the mean differential value of each sensor should be selected as the optimal feature extraction method for E-nose data, and raw data comparison results showed that 19 peak\/valley values and two slope values were extracted. While the format of E-nose data was in accord with the input format for CNN, the VIS\/NIR spectrometer data required matrixing to meet the format requirements. The LDA and PLSR analysis results showed that CNN has superior detection ability, being able to acquire more local features than the traditional method, but it has the risk of mixing in redundant information, which can act to reduce the detection ability. Multi-source information fusion (E-nose and VIS\/NIR spectrometer fusion) can collect more features from different angles to improve the detection ability, but it also contains the risk of adding redundant information, which reduces the detection ability. For practical detection, the type of Pu\u2019er tea should be recognizable using a VIS\/NIR spectrometer and the traditional feature extraction method. The blended ratio of Pu\u2019er tea should also be identifiable by using a VIS\/NIR spectrometer with traditional feature extraction. Multi-source information fusion with traditional feature extraction should be used if the accuracy requirement is extremely high; otherwise, a VIS\/NIR spectrometer with traditional feature extraction is preferred.<\/jats:p>","DOI":"10.3390\/s19102359","type":"journal-article","created":{"date-parts":[[2019,5,23]],"date-time":"2019-05-23T03:22:03Z","timestamp":1558581723000},"page":"2359","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Detection of Type, Blended Ratio, and Mixed Ratio of Pu\u2019er Tea by Using Electronic Nose and Visible\/Near Infrared Spectrometer"],"prefix":"10.3390","volume":"19","author":[{"given":"Sai","family":"Xu","sequence":"first","affiliation":[{"name":"Public Monitoring Center for Agro-Product of Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China"},{"name":"Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiuxiu","family":"Sun","sequence":"additional","affiliation":[{"name":"Indian River Research and Education Center, University of Florida, Ft. Pierce, FL 34945, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huazhong","family":"Lu","sequence":"additional","affiliation":[{"name":"Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China"},{"name":"College of Engineering, South China Agricultural University, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qianqian","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Engineering, South China Agricultural University, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,22]]},"reference":[{"key":"ref_1","first-page":"391","article-title":"Genetic Diversity and Relationship of Tea Germplasm in Yunnan Revealed by ISSR Analysis","volume":"36","author":"Liu","year":"2010","journal-title":"Acta Agron. 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