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Detection of Thrips Defect on Green-Peel Citrus Using Hyperspectral Imaging technology Combining PCA and B-Spline Lighting Correction Method

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Journal of Integrative Agriculture 2014年第10期13卷 2229-2235页

作者： DONG Chun-wang YE Yang ZHANG Jian-qiang ZHU Hong-kai LIU Fei tea Research Institute Chinese Academy of Agricultural Sciences School of food and Biological engineering Jiangsu University

In order to find an effective method of detecting thrips defect on green-peel citrus, a defect segmentation method was developed using a single threshold value based on combination of characteristic wavelengths principal component analysis （PCA） and B-spline lighting correction method in this study. At first, four characteristic wavelengths （523, 587, 700 and 768 nm） were obtained using PCA of Vis-NIR （visible and near-infrared） bands and analysis of weighting coefficients; secondarily, PCA was performed using characteristic wavelengths and the second principal component （PC2） was selected to classify images; then, B-spline lighting correction method was proposed to overcome the influence of lighting non-uniform on citrus when thrips defect was segmented; finally, thrips defect on citrus was extracted by global threshold segmentation and morphological image processing. The experimental results show that thrips defect in citrus can be detected with an accuracy of 96.5% by characteristic wavelengths PCA and B-spline lighting correction method. This study shows that thrips defect on green-peel citrus can be effectively identified using hyperspectral imaging technology.

关键词： hyperspectral images principal component analysis lighting correction green-peel citrus thrips defect

Determination of carbendazim in tea using surface enhanced Raman spectroscopy

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Chinese Chemical Letters 2015年第12期26卷 1455-1459页

作者： Chun-Hua Ma Jing Zhang Yong-Cong Hong Yi-Ru Wang Xi Chen College of tea and food Science/Collaborative Innovation Center of Chinese Oolong tea Industry Wuyi University department of Chemistry and The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation College of Chemistry and Chemical EngineeringXiamen University

Surface-enhanced Raman scattering（SERS） is applied to detect the concentration of carbendzim（CBZ） in tea leaves. Au colloid is selected and used for active surfaces, and the extraction conditions are optimized in the experiment. The linearity range for the SERS intensity and the concentration of CBZ is found to be0.5 to 8 mg kgà1. The detection limit for CBZ is 0.1 mg kgà1and its recovery in tea samples is 72.3%. The detection results for CBZ using this method are compared with those of HPLC, and no obvious difference can be found. In addition, by dripping the condensed Au colloid on the tea leaves, the proposed SERS approach could be used to the in-situ determination of the half life period of CBZ on tea leaves.

关键词： SERS colloid linearity pesticide condensed filtered preparations listed attributed consuming

pH effect on the formation of THM and HAA disinfection byproducts and potential control strategies for food processing

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Journal of Integrative Agriculture 2017年第12期16卷 2914-2923页

作者： Yen-Con Hung Brian W.Waters Veerachandra K.Yemmireddy Ching-Hua Huang department of food Science and technology The University of Georgia department of food Science and technology The Ohio State University School of Civil and Environmental engineering Georgia Institute of Technology

Chlorine-based sanitizers have seen wide spread use in food sanitation. The reaction of chlorine species with organic matter is a concern for two reasons. Available chlorine can be “used up” by organic compounds resulting in a lower amount of chlorine available for disinfection. Another concern is that some forms of chlorine can react with some organic compounds to form toxic halogenated disinfection byproducts（DBPs）. Many studies have been conducted to evaluate the role of hypochlorous acid（HOCl） and hypochlorite ion（OCl–） in the production of DBPs with a particular interest in the production of trihalomethanes（THMs） and haloacetic acids（HAAs）. Since most of the chlorine reactions are pH dependent, pH is found to have a significant effect on the formation of chlorine DBPs. In many cases, the concentration of THMs decreases and HAAs increases as pH decreases. pH also plays an important role in the determination of the type and amount of DBPs formed, with lower, more acidic, pHs resulting in the formation of less chloroform. This review summarizes the information from the literature on the role of chlorine-based sanitizers as affected by pH in the formation of different types of DBPs. Alternative novel strategies to minimize the formation of DBPs are also discussed.

关键词： sanitizer chlorine disinfection byproducts pH hypochlorite

Effect of elevated [CO_2] and nutrient management on wet and dry season rice production in subtropical India

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The Crop Journal 2015年第6期3卷 468-480页

作者： Sushree Sagarika Satapathy Dillip Kumar Swain Surendranath Pasupalak Pratap Bhanu Singh Bhadoria Agricultural and food engineering department Indian Institute of Technology Kharagpur Orissa University of Agriculture and technology

The present experiment was conducted to evaluate the effect of elevated [CO_2] with varying nutrient management on rice–rice production system. The experiment was conducted in the open field and inside open-top chambers(OTCs) of ambient [CO_2](≈ 390 μmol L-1) and elevated [CO_2] environment(25% above ambient) during wet and dry seasons in 2011–2013at Kharagpur, India. The nutrient management included recommended doses of N, P, and K as chemical fertilizer(CF), integration of chemical and organic sources, and application of increased(25% higher) doses of CF. The higher [CO_2] level in the OTC increased aboveground biomass but marginally decreased filled grains per panicle and grain yield of rice, compared to the ambient environment. However, crop root biomass was increased significantly under elevated [CO_2]. With respect to nutrient management, increasing the dose of CF increased grain yield significantly in both seasons. At the recommended dose of nutrients, integrated nutrient management was comparable to CF in the wet season, but significantly inferior in the dry season, in its effect on growth and yield of rice. The [CO_2] elevation in OTC led to a marginal increase in organic C and available P content of soil, but a decrease in available N content. It was concluded that increased doses of nutrients via integration of chemical and organic sources in the wet season and chemical sources alone in the dry season will minimize the adverse effect of future climate on rice production in subtropical India.

关键词： Climate change Nutrient management Elevated [CO2] Rice yield Soil fertility

Effects of fermentation time on phenolic composition, antioxidant and antimicrobial activities of green, oolong, and black teas

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food Bioscience 2022年第5期49卷 322-330页

作者： Sinem Salman Gülsüm¨Oz Rasih Felek Ayhan Haznedar Turgay Turna Feramuz¨Ozdemir department of food engineering Faculty of EngineeringAkdeniz University07070AntalyaTurkey department of Microbiology Faculty of DentistryAkdeniz University07070AntalyaTurkey Atatürk tea Garden Cultures Research Institute Turkish Tea Board(Çaykur)53100RizeTurkey

In this study, it was aimed to investigate the effect of fermentation degree on total phenolic content, individual catechins, gallic acid, theaflavins, caffeine content, antioxidant and antimicrobial activity in teas. Green tea, black tea and oolong tea (partially oxidized 7 different degrees) were produced from the same cultivar of tea leaves harvested in first shooting period. The higher degree of fermentation was resulted in higher theaflavins, however in lower individual catechins and total phenolic content. Standard catechins gradually decreased with extended fermentation duration and epigallocatechin gallate decreased 87% from green tea to oolong to black tea. Higher antioxidant activity was observed in green and lower fermented oolong teas. There were significant (p0.9) between DPPH, ABTS assays and total phenolic content, catechin, epigallocatechin gallate, epicatechin, epicatechin gallate and total catechins. Significant (p0.7) were also observed between ORAC and those catechins. Moreover, the tea samples especially green tea showed antibacterial effects against three of the tested pathogenic bacteria Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853 and antifungal effects against Candida albicans ATCC 10231. However, no antimicrobial activity was detected against Escherichia coli.

关键词： Black tea Green tea Oolong tea Fermentation degree Catechins Antimicrobial activity

Additivity of pore structural parameters of granular activated carbons derived from different coals and their blends

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International Journal of Mining Science and technology 2016年第4期26卷 661-667页

作者： Yao Xin Xie Qiang Yang Chuan Zhang Bo Wan Chaoran Cui Shanshan School of Chemical and Environmental engineering China University of Mining and Technology department of Chemical and food engineering Hefei University of Technology

A series of granular activated carbons （GACs） were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET specific surface area （SBEr）, total pore volume （Vr） and average pore diameter （da） were measured and cal- culated as well as process parameters such as yield of char （CY） and burn-off （B）. The relationship between the pore structural parameters of the GAC from coal blend （BC-GAC） and the ones of the GACs from corresponding single coals （SC-GACs） was analyzed, in which an index, the relative error （δ）, was presented to define the bias between fitted values and experimental values of these parameters of the BC-GACs. The results show that the BC-GAC keeps qualitatively the pore structural features of the SC-GACs; as concerned as the quantitative relationship, the pore structural parameters of the BC-GAC from coal blend consisting of non-caking coals can be obtained by adding proportionally the pore structural parameters of the SC-GACs with a less than 10%. Meanwhile, for the BC-GAC from coal blend containing weak caking bituminous coal, the δ increases up to 25% and the experimental pore size distribution differs greatly from the fitted one.

关键词： Granular activated carbon Coal blend Pore structural parameters Additivity

Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals

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Journal of Environmental Sciences 2016年第5期28卷 91-98页

作者： Yinglong Sun Guangxia Qi Xuefei Lei Hui Xu Lei Li Chao Yuan Yi Wang department of Environmental engineering School of Environment Tsinghua University department of Environmental Science and engineering School of Food and Chemical EngineeringBeijing Technology and Business University

The radioactivity of uranium in radioactive coal bottom ash（CBA） may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride（HF） leaching, Siroquant（Rietveld） quantification, magnetic separation, and electron probe microanalysis（EPMA）. The Tessier sequential extraction showed that the uranium in the residual and Fe–Mn oxide fractions was dominant（59.1%and 34.9%, respectively）. The former was mainly incorporated into aluminosilicates,retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite（Fe_3O_4） and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment.

关键词： Coal bottom ash Uranium Radioactivity Tessier sequential extraction Magnetic separation

High-quality instant black tea manufactured using fresh tea leaves by two-stage submerged enzymatic processing

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food Science and Human Wellness 2022年第3期11卷 676-685页

作者： Junhao Kong Xiufang Yang Xiaobo Zuo Xiaoqin Su Bing Hu Xinle Liang department of Biochemical engineering Zhejiang Gongshang UniveristyHangzhou 310018China Hangzhou tea Research Institute China COOPHangzhou 310016China Zhejiang Key Laboratory of Transboundary Applied technology for tea Resource Hangzhou 310016China Haixi tea Deep Processing Institute Zhangzhou 363007China College of food Science and technology Nanjing Agricultural UniversityNanjing 210095China

Repeated thermal treatment could impair the flavor of instant black tea(IBT)as the volatile compounds and characteristic constituents dramatically vary during the manufacturing *** of fresh leaves as raw material in IBT manufacture at low temperature may become an alternative to conventional extraction *** study aimed to improve the quality of IBT using fresh tea leaves by a two-stage enzymatic *** influence of combined enzymatic oxidation and extraction conditions for maximal extractable flavour(taste and aroma)characteristics from fresh tea leaves were *** changes of aroma profiles and chemical constituents including theaflavins(TFs),thearubigins(TRs),theabrownines(TBs)and TRs/TFs ratio in converted tea brews under two-stage enzyme catalyzed fermentation and extraction conditions were further compared between different treatments,based on which the optimised conditions were *** the two-stage enzymatic processing,75 kinds of volatile compounds were identified in all processed samples,and the contents of TFs,TRs,TBs and TRs/TFs ratio could be optimized by adjusting different procedures and *** overall properties of final product were compared with two types of commercial *** quality IBT with desired properties and antioxidant activity can be manufactured using fresh tea leaves by two-stage enzymatic processing approach.

关键词： Instant black tea Liquid-state fermentation Enzymatic-enhanced extraction Quality characteristics

Comparative analysis of spray-drying microencapsulation of Lacticaseibacillus casei in synbiotic legume-based beverages

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food Bioscience 2022年第6期50卷 1605-1614页

作者： Smriti Chaturvedi Snehasis Chakraborty department of food engineering and technology Institute of Chemical TechnologyMumbai400019India

This study investigated the effect of three carrier agents, viz. maltodextrin (MD), gum acacia (GA), and xanthan gum (XG), on three synbiotic legume-based beverages subjected to optimized spray-drying conditions. Several characteristics of the encapsulated synbiotic powders were evaluated, including moisture content, bulk, and tapped density, dissolution encapsulation efficiency, flow properties, particle density, porosity, color, and powder yield. The survivability of probiotic bacteria Lacticaseibacillus casei ATCC 335 was also observed under gastric acid, bile salts, and simulated gastrointestinal tract. The results showed that while the higher powder yield (11–23%) was shown by MD-coated beverage powders, GA-coated beverage powders showed better encapsulation efficiency (79.9–89.3%) as well as lower moisture content values (7 log CFU/mL) in the case of gastrointestinal simulation and under gastric acid and bile juice. The scanning electron microscopy also showed the desirable particle morphology and formation of microcapsules preserving the probiotic activity. The thermal properties of GA-coated KB powder showed the peak degradation temperature as 143.44 °C, which suggested the use of appropriate drying temperatures for making stable encapsulated synbiotic powders. Thus, GA-coated KB powder holds the potential to be used as a functional food with synbiotic properties along with acceptable powder characteristics and maximum probiotic survivability.

关键词： Carrier agents In-vitro gastrointestinal digestion Probiotic Non-dairy Prebiotics