Search Results (98)

Real-time measurement of tea bud phenotypes via mobile devices is constrained by model lightweighting challenges, and research on non-contact measurement of tea bud phenotypes based on key points remains largely unexplored. Information on the growth posture of tea buds is an important basis for determining tea maturity grades, quality monitoring, and tea breeding. Therefore, this work develops a deep learning-enabled YOLOv8p-Tea model to estimate key point information of tea bud posture and automatically obtain three-dimensional point cloud information of tea buds by integrating depth information, thereby achieving in situ measurement of tea bud phenotypic parameters. Meanwhile, the model is trained and validated using a tea bud (one-bud-three-leaf) image dataset, and its effectiveness is demonstrated through experiments. Compared to the YOLOv8p-pose model, the model achieves a mAP50 of 98.3%, a P of 97%, and parameters of 0.72 M, with mAP50 and P improved by 1.5% and 1.9%, respectively, and the parameter count is reduced by 25%. To validate the accuracy of phenotypic extraction, the model was deployed on edge devices, and 30 tea buds with one bud and three leaves were randomly selected in a tea garden. The final in situ measurement results showed an MRE of 6.63%. Experimental findings indicate that the developed method is capable of not only effectively estimate tea bud posture but also accurately achieves in situ measurement of tea bud phenotypes, which holds potential applications for meeting the construction needs of smart tea gardens and optimizing tea breeding. Full article

To address the need for rapid evaluation of large batches of Mee rough tea during the acceptance stage, this study aims to explore the feasibility of using portable Fourier transform near-infrared (FT-NIR) spectroscopy for preliminary quality screening. The goal is to develop a rapid, non-destructive, and relatively objective assessment method that is applicable to practical acceptance scenarios. This work represents an exploratory proof-of-concept study rather than a finalized industrial grading solution. Spectral data of three reference categories and thirty-six test samples were collected in the wavelength range of 1350–$2500\mathrm{nm}$ using a portable FT-NIR spectrometer. The sample configuration was designed to simulate practical acceptance sampling conditions. The spectra were preprocessed using multiplicative scatter correction, first-order derivative transformation, and mean-centering. Independent principal component analysis (PCA) models were constructed for each reference category to achieve class-wise feature dimensionality reduction, with cumulative explained variance exceeding $95\%$. Distance thresholds were determined using the $3\sigma$ principle based on Euclidean distance and Mahalanobis distance. Classification was performed by distance-based matching between test samples and reference categories. Under optimized matching degree threshold settings of $0.9$ and $0.7$, the two distance models achieved classification accuracies of $86.11\%$ and $83.33\%$, respectively, demonstrating the feasibility of the proposed approach. The main contribution of this study is the application of class-wise PCA combined with distance-based discrimination to the acceptance stage of Mee rough tea. The proposed framework provides a practical exploratory approach for rapid screening and offers a preliminary digital tool to support acceptance decisions. Further validation using larger and more diverse datasets will be necessary prior to large-scale industrial implementation. Full article

Tea offers health benefits, but some teas accumulate high fluoride (F), posing fluorosis risks. However, the roles of individual tea components in regulating F bioavailability remain unclear. This study investigated the effects of major tea constituents on F metabolism in male rats (n = 5/group) administered F (40 mg/L) alone or with graded doses of epigallocatechin gallate (EGCG, 150–450 mg/kg); theaflavins, thearubigins, and theabrownin (TFs, TRs, TB, 200–800 mg/kg each); tea polysaccharides (TPSs, 25–250 mg/kg); and calcium and aluminum (Ca, Al, 800–3200 µg/kg each) via gavage. Pharmacokinetic analysis of plasma F (0–480 min) and fecal F excretion were assessed. The result showed that high-dose EGCG (450 mg/kg) reduced C_max by 61.76% and total exposure (AUC_0–t) by 37.48% compared to the control, while significantly increasing fecal F by 26.79% (p < 0.05). TB (800 mg/kg) delayed F absorption by prolonging T_max from 18 to 30 min and reduced C_max by 35.38% (p < 0.05). TPS (250 mg/kg) decreased C_max by 51.72% and AUC_0–t by 24.38% (p < 0.05). Ca and Al (800–3200 µg/kg) reduced C_max by 39.19–69.62%, and low-dose aluminum (800 µg/kg) increased fecal F by 35.58% (p < 0.05). These findings elucidate distinct roles of tea constituents in mitigating F bioavailability, providing a scientific basis for tea safety assessment and dietary interventions against F overexposure. Full article

Rosehip-based products are rich in polyphenols with recognized health benefits, making accurate characterization essential for quality control and functional evaluation. Conventional analytical approaches for polyphenol determination are often time-consuming, costly, and environmentally demanding. In this study, a sustainable analytical method based on capillary zone electrophoresis coupled with diode array detection (CE–DAD) was developed as a green and accessible screening method for polyphenol analysis in rosehip-based products. Twelve polyphenolic compounds belonging to different classes (stilbenes, flavonols, flavanols, flavanones, and flavones) were used to optimize the electrophoretic conditions, including the buffer pH, voltage, and electrolyte concentration. Herbal tea and supplement samples were analyzed before and after a simple cartridge-based clean-up step to reduce matrix interferences. The method enabled simultaneous profiling of multiple polyphenol classes in a single CE–DAD run, showing excellent linearity (R² > 0.99), run to run reproducibility (RSD 0.8–1.6%), and sensitivity (LOD 0.4–1.4 μg/mL; LOQ 0.9–4.7 μg/mL). Eight target polyphenols were identified and quantified in real samples. Polyphenol profiling was complemented by DPPH and ABTS antioxidant assays, allowing a functional interpretation of compositional data and a case-based comparison between different product formulations. Specifically, the herbal tea showed the values of a 13.8 mg Trolox/g sample (80.5% DPPH inhibition) and 15.3 mg Trolox/g sample (98.5% ABTS inhibition), whereas the food supplement presented a 7.4 mg Trolox/g sample (34.2% DPPH inhibition) and 7.4 mg Trolox/g sample (54.1% ABTS inhibition). Method sustainability and applicability were also evaluated using the Blue Applicability Grade Index (BAGI), confirming a low environmental footprint. Full article

This study investigated the aroma characteristics of three grades of raw tea leaves and their corresponding jasmine tea products from Guangxi, China. Aromatic profiles of jasmine tea varieties were analysed using two-dimensional gas chromatography-olfactory-mass spectrometry (GC×GC-O-MS), stir bar sorptive extraction (SBSE), and descriptive sensory evaluation. Chemometric methods were applied to compare sensory scores with instrumental data. Volatile compound concentrations and relative odour activity values (r-OAVs) were calculated. The results indicated significant differences in base tea leaf quality: high-grade tea leaf G1 exhibited pure, sweet characteristics, serving as an excellent aroma-absorbing carrier. The scenting process significantly imparted jasmine fragrance to the finished product, although its efficacy was constrained by tea leaf grade. GH1 finished tea exhibited a fresh, vibrant, and rich aroma with a sweet, mellow fragrance and high floral integration. In contrast, GH3, due to its inferior base material quality, yielded a weak aroma after scenting with limited quality improvement. The initial quality of the tea base is the fundamental determinant of the upper limit of the finished jasmine tea’s sensory quality, while the scenting process is the core means of shaping its signature floral aroma. The combination of high-quality tea leaves and precise scenting techniques is essential for developing the fresh, vibrant, and rich flavour profile of premium jasmine tea. This study reveals that the flavour formation of jasmine tea originates from the foundational quality of the tea leaves, providing a theoretical basis for monitoring the aroma quality of jasmine tea produced from different grades of tea leaves. Full article

To address the challenge of disconnection between cultural and ecological values in Linear Cultural Heritage (LCH) conservation, this study examines the Jinzhong section of the Great Tea Road to develop a dual-dimensional framework for corridor identification and collaborative governance. The research establishes a dual-value evaluation system encompassing cultural and ecological dimensions, applied to grade 422 heritage sites. A potential corridor network is subsequently generated using the Minimum Cumulative Resistance (MCR) model. The study innovatively integrates the Multiple Centrality Analysis (MCA) model, employing heritage site values as network weights to identify and classify two primary corridor types: “culture-dominant” and “ecology-dominant” corridors. Through spatial overlay analysis, a ‘culture–ecology composite corridor’ network is ultimately constructed. The results demonstrate that the cultural value network exhibits a “monocentric” clustering pattern, whilst the ecological value network displays a “multicentric, networked” configuration, revealing significant spatial disjunction between the two systems. This analysis enables the identification of three corridor typologies—culturally dominant, ecologically dominant, and composite corridors integrating both values—alongside the positioning of key connectivity hubs and network vulnerability points across distinct value zones. The proposed “dual-dimension Multiple Centrality Analysis analytical framework” transforms the abstract concept of cultural–ecological value coupling into a quantifiable spatial analysis pathway, thereby addressing existing research gaps. This framework provides refined decision-making support for both conservation practices and World Heritage nomination processes of the Jinzhong section of the Great Tea Road, whilst offering a replicable scientific methodology for conserving comparable linear heritage sites globally. Full article

As the raw material for tea making, the quality of fresh tea leaves directly affects the quality of finished tea. Traditional manual sorting and machine sorting struggle to meet the requirements for high-quality tea processing. Based on machine vision and deep learning, intelligent grading technology has been applied to the automated sorting of fresh tea leaves. However, when faced with machine-picked tea leaves, the characteristics of complex morphology, small target recognition size, and dense spatial distribution can interfere with accurate category recognition, which in turn limits classification accuracy and consistency. Therefore, we propose an enhanced YOLOv12 detection framework that integrates three key modules—C3k2_EMA, A2C2f_DYT, and RFAConv—to strengthen the model’s ability to capture delicate tea bud features, thereby improving detection accuracy and robustness. Experimental results demonstrate that the proposed method achieves precision, recall, and mAP@0.5 of 81.2%, 90.6%, and 92.7% in premium tea recognition, effectively supporting intelligent and efficient tea harvesting and sorting operations. This study addresses the challenges of subtle fine-grained differences, small object sizes, variable morphology, and complex background interference in premium tea bud images. The proposed model not only achieves high accuracy and robustness in fine-grained tea bud detection but also provides technical feasibility for intelligent fresh tea leaves classification and production monitoring. Full article

Grade and cultivar are the important factors influencing white tea quality, but their relative metabolic contributions are not fully understood. Twelve white tea samples representing four major Fujian cultivars across three grades were analyzed using UHPLC–MS-based non-volatile metabolomics, HS-SPME–GC–MS volatile profiling, and sensory correlation analysis. In total, 47 non-volatile and 21 volatile markers were associated with grade differences, while 44 non-volatile and 26 volatile markers were linked to cultivar differences. Catechins and amino acids declined as grade decreased, whereas flavonol glycosides and gallic acid increased, accompanied by stronger astringency and reduced umami and sweetness. Aroma profiles showed a similar trend, with higher-grade teas dominated by floral notes and lower-grade teas exhibiting more herbal characteristics. Dimeric catechins, oxylipins, and aroma glycosides varied among cultivars. Volatile profiles separated the cultivars into two aroma groups: Fuding Dabai and Fuding Dahao showed more floral–fruity aromas, whereas Fuan Dabai and Zhenghe Dabai exhibited stronger herbal and aged aromas. Odor activity value analysis showed that linalool, geraniol, and (E,Z)-3,6-nonadien-1-ol were among the most abundant aroma-active compounds across white tea samples. These results provide chemical evidence for distinguishing white tea by grade and cultivar, with potential relevance to quality evaluation. Full article

Sustainable strategies for revalorizing food industry by-products are increasingly relevant in the development of modern experimental dermato-cosmetic formulations. In this study, two semisolid cosmetic creams (R10 and EM-R10) were designed using recycled palm oil—physically purified after intensive frying—as the lipid phase. The recycled oil was incorporated strictly within a controlled experimental framework and does not imply cosmetic-grade regulatory compliance. The formulations incorporated distinct bioactive profiles: R10 combined apricot and pineapple extracts with lime essential oil, while EM-R10 integrated fir bud and green tea extracts alongside the same essential oil. Both preparations contained Fragard as a preservative and niacinamide and panthenol as vitaminic components. The physicochemical properties of the formulations were assessed through rheology, confocal microscopy, ATR-FTIR, SEM, DSC, and contact angle measurements. Antimicrobial activity was evaluated against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans using disk diffusion and broth microdilution assays. The results demonstrate that, despite partial thermal degradation, recycled palm oil retains modified structural features that influence formulation-related properties relevant to topical systems. EM-R10 showed superior spreadability, adhesion, stability, and diffusion-related performance, as well as improved antimicrobial activity, within the investigated experimental conditions, highlighting recycled palm oil as a promising sustainable lipid phase for experimental dermato-cosmetic formulations, pending further purification, toxicological evaluation, and regulatory compliance assessment. Full article

Background: Excess adiposity induces low-grade inflammation, including increased C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Green tea contains epigallocatechin gallate (EGCG), with anti-inflammatory potential. EGCG metabolism is influenced by individual variations in catechol-O-methyltransferase (COMT) genotypes. Objectives: To evaluate the effect of green tea extract (GTE) supplementation on circulating inflammatory cytokines among postmenopausal women with overweight or obesity and differing COMT genotypes. Methods: This study is a secondary analysis of a random subset (N = 97) from the Minnesota Green Tea Trial (MGTT), a randomized double-blinded placebo-controlled trial. The intervention was a high-dose GTE supplement (843 ± 44 mg EGCG/day) or placebo for 1 year. Serum CRP, TNF-α, and IL-6 were measured at 0, 6, and 12 months. Absolute changes in inflammatory cytokines from baseline to month 12 were evaluated using linear mixed-effects models adjusted for age, body mass index (BMI), smoking history, physical activity, and vitamin supplement use. Results: The changes from month 0 to month 12 were not statistically different between the groups for any of the inflammatory cytokines measured. The overall treatment effect was not statistically significant for CRP (p = 0.24), IL-6 (p = 0.59), TNF-α (p = 0.36), nor for the interaction between treatment group and time (all Ps > 0.40). There was no significant interaction between treatment group and COMT genotype for the stated markers. Conclusions: A high-dose GTE supplement consumed daily for one year did not significantly decrease inflammatory cytokines among postmenopausal women with overweight or obesity. The COMT genotype did not modify the effects of GTE supplementation on inflammatory cytokines. Future studies with a larger sample size among those at high risk of systemic inflammation are warranted. Full article

Fu brick tea (FBT) develops its characteristic qualities through fermentation, yet how variation in the chemical composition of raw dark tea (RDT) is associated with microbial succession and final tea quality remains unclear. In this study, three grades of RDT (premium-grade (1M), first-grade (2M), and second-grade (3M)) were processed into FBT under identical conditions to examine the relationship between initial composition, microbial community structure, and sensory attributes. Results revealed that high-grade RDTs (1M) contained higher levels of water extracts (WE, 36.35 ± 0.14 (%), p < 0.05), total polyphenols (TP, 14.93 ± 0.19 (%), p < 0.05), and free amino acids (FAA, 2.90 ± 0.03 (%), p < 0.05), promoting Aspergillus (96.06% in C1M, compared with 66.43% in C2M and 55.01% in C3M) dominance and resulting in brighter liquor with enhanced body and smoothness. Correlation analyses demonstrated a coherent sequence from substrate composition to microbial assembly and then to quality-related chemistry. WE, TP, and FAA were positively correlated with Aspergillus abundance and body and smoothness (p < 0.05), whereas soluble sugars correlated with Rhodotorula and sweetness (p < 0.05). These findings support a substrate-mediated association framework in which the chemical composition of RDT is closely aligned with microbial community structure and sensory differentiation during FBT fermentation, providing a scientific basis for raw material grading and fermentation management in dark tea production. Full article

Linear cultural heritage is characterized by complex cross-regional and multi-level features, facing severe challenges of spatial resource fragmentation and an imbalance in cultural and tourism functions. However, existing research lacks quantitative analysis regarding the non-linear driving mechanisms of spatial distribution and the misalignment of culture–tourism coupling. In this study, we construct an integrated identification–explanation–coupling–governance (IECG) theoretical framework. Taking The Great Tea Road (Jinzhong Section) as a case study, our framework integrates the CCSPM, XGBoost-SHAP machine learning interpreter, and Geodetector to systematically quantify the spatial structure of heritage and the level of culture–tourism integration. The results indicate that, (1) in terms of spatial patterns, the study area exhibits an unbalanced agglomeration characteristic of “dual-primary and dual-secondary cores,” with high-density areas showing significant orientation along rivers and roads; (2) regarding driving mechanisms, the machine learning model reveals a significant “non-linear threshold effect,” with 83% of driving factors (e.g., elevation and distance to transportation) exhibiting non-linear fluctuations in their influence on heritage distribution; and, (3) in terms of culture–tourism coupling, the overall coupling coordination degree (CCD) is low (mean 0.38), indicating significant “resource–facility” spatial misalignment. The modern number of public cultural facilities (NCF) is identified as the primary obstacle restricting the transformation of high-grade heritage into tourism products. Based on these findings, we propose adaptive zoning governance strategies. This research not only theoretically clarifies the complexity of the social–ecological system of linear heritage but also provides a generalizable quantitative method for the digital protection and sustainable tourism planning of cross-regional cultural heritage. Full article

Microbial spoilage of nutrient-rich strawberries leads to considerable food waste and economic losses. Plant-derived phenolic compounds, including resveratrol (RES), epigallocatechin gallate (EGCG), and tea polyphenols (TP), have gained attention for their multi-target antimicrobial efficacy and potential applications in fruit preservation. This study evaluated the individual and combined effects of these three compounds on strawberries infected with Escherichia coli (E. coli) and Botrytis cinerea (B. cinerea). The minimum inhibitory concentration (MIC) values for RES (analytical grade, ≥99% purity) and EGCG (analytical grade, ≥98% purity) against E. coli were 1.56 g/L and 25 g/L, with an additive effect against E. coli growth (FICI = 0.625). 5 g/L TP (analytical grade, ≥98% purity) completely inhibited the mycelial growth of B. cinerea. The in vivo application of RES and EGCG significantly reduced spoilage and improved texture, color, weight retention, and flavor quality in strawberries infected by E. coli individually or in combination. Similarly, the combined use of TP and chitosan saved the quality of strawberries infected by B. cinerea compared to single treatments. This study provided new effective and eco-friendly strategies for the preservation of strawberries. Full article

Cu in tea leaves can be easily leached into the tea broth during brewing and ingested by humans; therefore, excessive accumulation of Cu in tea leaves may pose potential health risks. In this study, the relationship between soil Cu and Cu content in tea plantations was investigated by analyzing 106 surface soil samples (0–20 cm) and their corresponding tea samples from Anxi County. The distribution of Cu, ecological risk, and early warning indicators were analyzed in both tea and soil samples. Research indicates that soil Cu content is classified into five grades in accordance with the Specifications for Geochemical Evaluation of Land Quality: Grade I (>29 mg/kg, accounting for 7.55%), Grade II (24~29 mg/kg, accounting for 2.83%), Grade III (21~24 mg/kg, accounting for 3.77%), Grade IV (16~21 mg/kg, accounting for 8.49%), and Grade V (≤16 mg/kg, accounting for 77.36%). The mean soil Cu content varied with the underlying rock type, following the order: sedimentary rocks > metamorphic rocks > magmatic rocks. The spatial distribution of soil Cu content was higher in the north and lower in the southeast and northwest, whereas tea Cu content was higher in the southeast and northwest and lower in the central region. Soil-forming parent materials, traffic emissions, and agricultural activities were identified as the main sources of soil Cu, while tea Cu content was mainly affected by soil Cu and agricultural activities. Importantly, soil Cu posed no significant ecological risks, and all tea samples had Cu contents within safe limits without significant toxicity or health hazards. This study innovatively integrates Cu source identification, spatial analysis, and dual-dimensional (soil–tea) risk assessment in a typical tea-producing area, providing a targeted scientific basis for the precise monitoring and management of soil Cu in tea plantations and ensuring compliance of soil and tea products with national safety standards. Full article

Background: Ozonation is a non-thermal process that can remodel the chemistry and bioactivity of plant extracts. We evaluated whether ozonating green tea extract enhances its phenolic composition and in vitro bioactivity in relation to nutrition and food applications, with potential clinical applications. Methods: Ethanolic green tea extract (GTE) was exposed to ozone (0–7 L/min, 5 h) to yield an ozonated extract (GTOE). Phenolics were quantified by the HPLC. Bioactivities included antimicrobial testing (agar diffusion; MIC/MBC/MFC), antibiofilm formation, time-kill kinetics (0–180 min), bacteria-induced hemolysis in human RBCs, DPPH radical scavenging, pancreatic lipase inhibition, and scratch-wound closure in human fibroblasts. Data from n = 3 independent experiments were analyzed by one-way ANOVA with Tukey’s post hoc test (α = 0.05). Results: Ozonation increased gallic acid (3150.92 to 3229.69 µg/g) and ellagic acid (2470.66 to 2789.40 µg/g), while catechin decreased slightly (2634.09 to 2535.09 µg/g). Compared with GTE, GTOE produced larger inhibition zones and lower MIC/MBC/MFC against Candida albicans, Bacillus subtilis, Staphylococcus aureus, Klebsiella pneumoniae, and Salmonella typhi; Aspergillus niger remained unsusceptible. For example, inhibition zones for S. aureus and K. pneumoniae increased by 2–4 mm and MIC/MBC values were 2-8-fold lower. Candida albicans showed marked sensitivity (MFC 500 to 125 µg/mL). GTOE exhibited superior, dose-dependent antibiofilm activity across all tested strains, reaching up to 97.82% inhibition, (highest for S. aureus and S. typhi, at 75% MBC). GTOE reduced bacterial counts more rapidly than GTE across all tested strains, achieving full eradication within 150 min. Bacteria-induced hemolysis was inhibited by 97% at 75% MIC with GTOE, versus 93–96% with GTE. Antioxidant capacity improved (DPPH IC₅₀ 3.31 vs. 5.54 μg/mL), as did lipase inhibition IC₅₀ 6.06 vs. 17.69 μg/mL). Wound closure at 48 h increased (GTOE 61.1%; GTE 56.8%; control 50.8%). Conclusions: Controlled ozonation of green tea extract remodeled phenolics and consistently enhanced antimicrobial, antibiofilm, antioxidant, potential anti-obesity, and wound-healing activities in vitro. These results support food-grade optimization and safety/by-product profiling, followed by in vivo validation at diet-relevant doses, to enable nutrition, food, and potential clinical applications. Full article