Foods
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2022
·Vol. 11
·期 9
·1273
·
IF 5.561
Jie-Qiong Wang,Ying Gao,Dan Long,Jun-Feng Yin,Liang Zeng,Yan-Qun Xu,Yong-Quan Xu
Hydrogen peroxide has a significant effect on the flavor of tea beverages. In this study, the yield of hydrogen peroxide in (–)-epigallocatechin gallate (EGCG) solution was first investigated and found to be significantly enhanced under specific conditions, and the above phenomenon was amplified by the addition of linalool. Then, an aqueous hydrogen peroxide solution was added to a linalool solution and it was found that the concentration of linalool was significantly reduced in the above-reconstituted system. These findings were verified by extending the study system to the whole green tea infusions. The results suggested that the production of hydrogen peroxide in tea beverages may be dominated by catechins, with multiple factors acting synergistically, thereby leading to aroma deterioration and affecting the quality of tea beverages. The above results provided a feasible explanation for the deterioration of flavor quality of green tea beverages with shelf life.Keywords:green tea beverages;EGCG;hydrogen peroxide;linalool;flavor
研究领域:
食品科学
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化学
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饮料技术
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2018
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IF 3.909
Ruyi Li,Guiming Fu,Chengmei Liu,David Julian McClements,Yin Wan,Shaoman Wang,Ting Liu
The tannase (from Aspergillus niger ) was immobilised by glutaraldehyde conjugation to amino-functionalised chitosan-coated magnetic nanoparticles (Fe 3 O 4 -CS nanoparticles). Fourier-transform infrared spectroscopy and thermo-gravimetric analysis showed that chitosan was coated on the surface of magnetic nanoparticles. Transmission electron microscopy indicated that the synthesised nanoparticles (Fe 3 O 4 -CS) were almost spherical or ellipsoidal with an average diameter of 5.97 ± 1.25 nm. The stability and functionality of free and immobilised tannase were compared. Both forms of tannase exhibited the same optimal temperature of 30 °C, whereas the optimal pH value of immobilised tannase (pH 4.5) was lower than that of the free tannase (pH 5.5). The pH and thermal stabilities of immobilised tannase were significantly better than those of free tannase. Immobilised tannase retained over 50% of its initial activity after repeated utilisation for eight cycles. Furthermore, the immobilised tannase effectively improve the clarity and colour of black and green tea infusions. These results showed that amino-functionalised Fe 3 O 4 -CS nanoparticles are an efficient carrier for immobilising tannase, and immobilised tannase can be used in the clarification of tea infusion.
研究领域:
生物技术
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食品科学
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2019
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IF 3.206
Li Gao,Longhui Liu,Yaming Sun,Wenjie Zhao,Lijun He
A novel azamacrocycle-based adsorbent for solid-phase extraction was synthesized by coupling a 26-membered aromatic-aliphatic-mixed azamacrocycle to 3-chloropropyltrimethoxylsilane-modified silica. The obtained material was characterized by elemental analysis and fourier transform-infrared spectroscopy. The adsorbent showed excellent performance for extracting organophosphorus pesticides (fenitrothion, parathion, fenthion and phoxim), which may be due to multiple interactions between the adsorbent and organophosphorus pesticides, including π–π, hydrophobic, dipole-dipole, charge-transfer, hydrogen-bonding and inclusion interactions. The main parameters that affected the extraction efficiency were investigated, including the amount of adsorbent, the volume and flow rate of the sample solution, the elution solvent and the ionic strength. This azamacrocycle-based extraction technique was further combined with high-performance liquid chromatography to measure trace organophosphorus pesticides in tea drinks. The method showed good linearity (5–500 ng/mL), low limit of detection (0.10 ng/mL), and high recoveries from spiked samples (90.4%–113.5%) were obtained with low relative standard deviation (0.6%–8.9%, n = 3). The azamacrocycle-based adsorbent showed good extraction performance and offered a promising application in the extraction of organophosphorus pesticides from complicated tea drinks.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
FOOD CHEMISTRY
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2024
·
IF 8.5
Meng Tao,Wenli Guo,Jin Liang,Zhengquan Liu
The occurrence of the cooked off-flavor during the thermal sterilization of green tea beverages negatively impacts their quality. This study aimed to identify the key cooked off-flavor compounds by molecular sensory science. The increase of 12 compounds, including malty (e.g., 3-methylbutanal), floral (e.g., linalool), sweet (e.g., methional), and smoky (2-methoxy-4-vinylphenol) compounds, contributed to the development of the cooked off-flavor. Additionally, the loss of five aroma compounds—dimethyl sulfide, ( E ) -β- ionone, 2-methylbutanal, 1-penten-3-one, and ( E,Z )-2,6-nonadienal—also caused the emergence this undesirable flavor. One potential solution to reduce the cooked off-flavor was the baking of tea raw materials. While baking did not significantly reduce the concentration of off-flavor compounds, it led to an increase in eight roasty aroma compounds, such as pyrazines and pyrroles, which helped partially mask the cooked off-flavor in green tea beverages.
研究领域:
食品科学
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分子感官科学
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PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2024
·
IF 4
Qing Wang,Xue Ren,Shao-Feng Tang
Background Limits on ametryn and benzo[a]pyrene in tea beverages are becoming more stringent. To enhance detection efficiency and reduce analysis costs, it is critical to develop mixed-mode extractants for these two analytes with substantial differences in properties concurrently. Biochar (BC) is increasingly being used in the preparation of mixed-mode adsorbents, but there is a challenge in balancing adsorption capacity against adsorption rate. Therefore, it is of great significance to explore mixed-mode adsorbents that can simultaneously adsorb or extract analytes with different properties, such as ametryn and benzo[a]pyrene, and achieve rapid adsorption or extraction. Results The shells of Zizyphus jujuba seeds were used to synthesize K-H-BC, a three-dimensional hierarchical porous BC with a wide range of oxygen-containing functional groups. The synthesis technique included KOH activation and modification using a 1:3 vol ratio of HNO 3 /H 2 SO 4 . K-H-BC's mixed-mode adsorption properties resulted in various interactions with ametryn and benzo[a]pyrene. It exhibited rapid adsorption rates for ametryn and benzo[a]pyrene (reaching equilibrium in 15 min and 5 min, respectively) as well as high adsorption capacities (487.64 mg g −1 and 133.16 mg g −1 , respectively). Using K-H-BC as a dispersed solid-phase extraction adsorbent, combined with high performance liquid chromatography, a method for simultaneously detecting the two analytes in tea beverages was established. Ametryn displayed a linear range of 2–500 μg L −1 with a limit of detection of 0.20 μg L −1 , while benzo[a]pyrene showed a linear range of 25–500 μg L −1 with a limit of detection of 2.12 μg L −1 . Significance and novelty It provides a solution to the problem of high hydrophobicity in KOH-activated BC by modifying it with mixed acids. K-H-BC possesses a three-dimensional hierarchical porous structure and abundant surface oxygen-containing functional groups, allowing it to retain high adsorption capacity during rapid adsorption while co-adsorbing and co-extracting analytes with significantly different properties. This research provides a reference for using BC in sample pretreatment and the comprehensive utilization of non-medicinal parts of Zizyphus jujuba .
研究领域:
环境科学
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分析化学
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2024
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IF 8
Panyu He,Xinglan Fu,Chenghao Wang,Yujiang Gou,Fengjing Cao,Hongwu Tian,Shixiang Ma,Yiyi Liang,Ting An,Guanglin Li
Tea infusion, as one of the most popular beverages, is favored by people around the world. However, tea plants accumulate heavy metals from the soil during growth, which are gradually transferred to the leaves and subsequently decomposed into the tea infusion after soaking in hot water. Long-term consumption of tea infusion containing heavy metals may lead to severe health issues, such as liver dysfunction and cancer. Therefore, rapid, precise, and highly sensitive detection of heavy metals in tea infusion becomes crucial for human health. Traditional methods, such as atomic absorption spectroscopy (AAS), suffer from long detection cycles, high costs, and the risk of secondary pollution from chemical extraction reagents. Thus, this paper presents a method, using laser-induced breakdown spectroscopy combined with electrospinning technology (LIBS-ES), to detect trace amounts of Cr and Cu in tea infusion. The electrospun nanofiber membranes (ENM) were modified with gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs), achieving ultra-sensitive detection of Cr and Cu. The experiment results show that the limits of detection for Cr and Cu are 5 μg/L and 10 μg/L, respectively. Moreover, this method was successfully applied to the detection of Cr and Cu in seven different types of tea infusion, achieving recovery rates of 99 %-106 % and 99 %-108 %, respectively. The method demonstrated good performance even under the interference of other ions at various concentrations, providing a reference for the rapid and highly sensitive detection of heavy metals in tea infusion.
研究领域:
食品科学
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环境科学
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分析化学
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DOI
高影响因子
Food Quality and Safety
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2022
·
IF 3.949
Kang Yuting,Li Chenghua,Li Huiru,Li Jing,Jiang Kezhi
Polycarboxylic acids (PACs) are important metabolic products in almost all living bodies, yet current analytical methods for detection of PACs in tea beverages are still unsatisfactory due to the complex matrix and physicochemical properties of PACs. In this work, a rapid method was developed for the simultaneous determination of 7 PACs, including tartaric acid, α-ketoglutaric acid, malic acid, malonic acid, cis-aconitic acid, succinic acid, and fumaric acid, in beverages, based on selective removal of the matrix in combination with liquid chromatography–mass spectrometry (LC-MS) analysis. By stirring with activated carbon and the Na2CO3 solution, the matrix in beverages was selectively removed, and PACs were almost retained in the supernatant of diluted Na2CO3 solution. Under optimized parameters, the limit of quantitation for the PACs was in the range of 1–50 ng/mL, and the content of the PACs in 8 beverages was determined with the recovery range of 72.2%–122.5%. The contents of malic acid, malonic acid, and succinic acid in tea beverages were found to be greater than those in non-tea beverages. Moreover, the concentration of these PACs in beverages was found to be multiplied many times in their deterioration period, especially for fumaric acid and α-ketoglutaric acid. These results indicated that PACs can be selected as a criterion to differentiate qualified tea beverages from spoiled beverages.
研究领域:
食品科学
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分析化学
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DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
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2022
·Vol. 46
·期 2
·2200661
·
IF 3.614
Wenhui Li,Ying Gu,Zikun Liu,Rimao Hua,Xiangwei Wu,Jiaying Xue
A novel solid-phase microextraction device coated with an efficient and cheap thin film of polyurethane was developed for trace determination of 13 widely used pesticides in fruit and tea beverages. A round-shaped polyurethane film covering the bottom of a glass vial was fabricated as the sorbent to exhibit a superior capacity for preconcentrating target compounds and reducing matrix interferences. After optimization of the key parameters including the film type, extraction time, solution pH, ionic strength, desorption solvent, and conditions, this device allowed an efficient adsorption-desorption cycle for the pesticides accomplished in one vial. Coupled with gas chromatography-electron capture detection, the polyurethane-coated thin film microextraction method was successfully established and applied for the analysis of real fruit and tea drinks, showing low limits of detection (0.001–0.015 μg/L), wide linear ranges (1.0–500.0 μg/L, r 2 > 0.9931), good relative recoveries (77.2%–106.3%) and negligible matrix effects (86.1%–107.5%) for the target pesticides. The proposed approach revealed strong potential of extending its application by flexibly modifying the type or size of the coating film. This study provides insights into the enrichment of contaminants from complex samples using inexpensive and reusable microextraction devices that can limit the environmental and health impact of the sample preparation protocol.
研究领域:
分析化学
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环境科学
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PubMed
高影响因子
Foods
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2022
·Vol. 12
·期 1
·8
·
IF 5.561
Xiaodong Huang,Huifang Liu,Xiaomin Xu,Ge Chen,Lingyun Li,Yanguo Zhang,Guangyang Liu,Donghui Xu
In this study, a novel composite material prepared by using deep eutectic solvent (tetrabutylammonium chloride-dodecanol, DES5) functionalized magnetic MWCNTs−ZIF−8 (MM/ZIF−8@DES5) was employed as an adsorbent for the magnetic solid-phase extraction of six pyrethroids from tea drinks. The characterization results show that MM/ZIF−8@DES5possessed sufficient specific surface area and superparamagnetism, which could facilitate the rapid enrichment of pyrethroids from tea drink samples. The results of the optimization experiment indicated that DES5, which comprised tetrabutylammonium chloride and 1-dodecanol, was selected for the next experiment and that the adsorption properties of MM/ZIF−8@DES5were higher than those of MM/ZIF−8 and M-MWCNTs. The validation results show that the method has a wide linear range (0.5–400 μg L−1, R2≥ 0.9905), low LOD (0.08–0.33 μg L−1), and good precision (intra-day RSD ≤ 5.6%, inter-day RSD ≤ 8.6%). The method was successfully applied to the determination of pyrethroids in three tea drink samples.Keywords:magnetic solid-phase extraction;deep eutectic solvent;ZIF−8;pyrethroids;tea drinks
研究领域:
分析化学
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环境科学
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2020
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IF 4.049
Heng Qian,Qian Yang,Yuan Qu,Ziwei Ju,Wenfeng Zhou,Haixiang Gao
Deep eutectic solvents (DESs) were used as an extractant for the determination of pyrethroids in environmental water and tea beverage samples. Three different acids were chosen as hydrogen bond donors for preparation of DESs, and decanoic acid was optimal because of its high recovery. Factors affecting relative recovery were optimized individually, including salt addition, surfactant addition, extraction temperature, DES amount, and sample volume etc. Under the optimized experimental conditions, the relative recovery of pyrethroids was from 89.3% to 97.7%, with relative standard deviation (RSD) values ranging from 1.75% to 2.73%. The linear correlation coefficient ranged from 0.9981 to 0.9992, and the linear range was between 1.9 and 500 μg/L. Based on a signal-to-noise ratio (S/N) of 3:1, the limit of detection (LOD) values were 0.56 to 1.24 μg/L. The enrichment factor ranged from 92 to 105. In conclusion, good extraction efficiency was achieved in tea beverage samples under the optimized conditions.
研究领域:
分析化学
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环境科学
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DOI
PubMed
高影响因子
Analytical Methods
·
2019
·Vol. 11
·期 38
·4923-4930
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IF 2.378
Heng Qian,Chaoran Liu,Qian Yang,Xinya Liu,Haixiang Gao,Wenfeng Zhou
Deep eutectic solvents (DESs), which consist of a mixture of hydrogen bond acceptor and hydrogen bond donor compounds, were used in liquid-phase microextraction, in which the extractant was dispersed in a porous ceramic film for the determination of pyrethroid pesticides in juice and tea beverage samples. Factors affecting recovery were optimized individually, which included salt addition, surfactant addition, extraction temperature, DES amount and sample volume. Based on the results of an optimized experiment, the recovery of pyrethroid pesticides is from 87.5% to 97.2% with relative standard deviation (RSD) values ranging from 1.68% to 2.86%. Determination coefficient was from 0.9981 to 0.9997 and the linear range was between 1.5 μg L−1 and 500 μg L−1. Based on a signal-to-noise ratio (S/N) of 3 : 1, the limit of detection (LOD) values were 0.45 μg L−1 to 1.30 μg L−1. The enrichment factor ranged from 93 to 106. For real samples, bifenthrin is found in black tea (Gold rougui) and oolong tea (Tieguanyin2); etofenprox is also found in the oolong tea (Tieguanyin3). In spiked samples, good extraction efficiency was achieved for all types of samples analyzed under the optimized conditions.
研究领域:
分析化学
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食品科学
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高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
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2012
·Vol. 236
·期 2
·303-310
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IF 1.566
Chen Guan-Lin,Hu Kun,Zhong Nan-Jing,Guo Juan,Gong Yu-Shi,Deng Xiao-Ting,Huang Ying-Si,Chu Da-Ke,Gao Yong-Qing
The total antioxidant capacity and total polyphenol content of 9 tea juices were examined following in vitro digestion model. Results show that there was a significant variation in total antioxidant capacity [16,392.30 ± 111.64–22,340.23 ± 46.73 μmol VC/L (DPPH), 3,194.24 ± 14.76–13,795.07 ± 37.46 μmol Trolox/L (ABTS), 2,540.61 ± 59.79–7,951.57 ± 31.91 μmol Trolox/L ferric reducing antioxidant power (FRAP)] and total polyphenol content (265.84 ± 9.52–876.62 ± 6.59 μg GAE/mL). Following the in vitro digestion, most of the juices of antioxidant capacities and 7 juices of the total polyphenol content were decreased. Before the in vitro digestion, a highly positive correlation was found between the total polyphenol content and FRAP value. After the gastric phase of digestion, there was a very strong positive linear correlation between the total polyphenol content and total antioxidant capacity. After the duodenal phase of digestion, the correlation between the total polyphenol content and total antioxidant capacity was very weak, and also, a very weak linear correlation was found between the antioxidant assays.
研究领域:
食品科学
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营养学
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生物化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）