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•Colorimetric sensor with spectral was attempted to classify different grades matcha.•Different classification methods were compared in developing identification ...models.•Back-propagation artificial neural network model had optimal prediction performance.•Volatile compounds differences between matcha grades were verified by HS-SPME-GC–MS.
Matcha tea powder is considered as an integral part of a healthy diet due to its enormous health benefits. In the current study, visible near-infrared (Vis-NIR) and colorimetric sensor array (CSA) techniques are applied to identify the matcha grades. The color-sensitive dyes reacted with their volatile compounds and the information was recorded by Vis-NIR spectroscopy, namely Vis-NIR-CSA. Specifically, three linear and three nonlinear classification models were compared, yielding the optimal identification rate by the back-propagation artificial neural network (BPANN) model with 99% and 98% in the calibration and prediction sets, respectively. The results indicated the sensor combined with the BPANN model could be applied satisfactorily in identification of different matcha grades. Additionally, the variations in volatile compounds between different matcha grades and eight characteristic volatile compounds were identified, which verified the sensor identification results. This study provided a scientific and novel method for the stability of matcha quality in production.
O estado obeso, caracterizado pelo excesso de acúmulo de gordura corporal, possui uma elevada incidência na população tornando-se problema de saúde pública. Diante disso, surge a necessidade de ...adotar estratégias para auxiliar no seu combate e das doenças crônicas não transmissíveis (DCNT) a ele associadas. Uma alternativa são os alimentos que possuem compostos bioativos como, por exemplo, o chá verde que pode auxiliar na oxidação de gordura, devido a concentração de catequinas. Além do chá verde - consumido apenas a infusão das folhas - outro tipo de chá também originário da Camellia sinensis ganha atenção na oxidação de lipídeos: o matcha, feito da maceração completa das folhas. Pesquisas mostraram que ele pode ter 137 vezes mais polifenóis, do tipo epigalocatequina-3-galato (EGCG), em relação ao chá verde tradicional. O objetivo desse trabalho é comparar a eficácia do matcha e chá verde como agentes lipolíticos, administrados diariamente em não praticantes de atividade física, sem dieta restrita, por 40 dias. Foram analisados dois grupos – chá verde (GCV) e matcha (GM), com dez pessoas cada. Foram realizadas análises bioquímicas e antropométricas dos participantes. Dentre os resultados, destaca-se a redução dos níveis séricos de glicose nos dois grupos, ambos com nível de significância **p < 0,01 para o teste t de student. Acredita-se que a EGCG iniba a atividade do transportador de glicose intestinal, levando a redução da captação de glicose no intestino. Logo, o chá verde e o matcha podem ser utilizados para diminuição de glicemia e outras complicações da obesidade. Em ambos os grupos, houve também diminuição de peso corporal, além de gordura livre, mas sem relevância estatística.
Matcha, a powder processed from tea leaves, has a unique green tea flavor and appealing color, in addition to many other sought after functional properties for a wide range of formulated food ...applications (e.g., dairy products, bakery products, and beverage). The properties of matcha are influenced by cultivation method and processing post-harvest. The transition from drinking tea infusion to eating whole leaves provides a healthy option for the delivery of functional component and tea phenolics in various food matrix. The aim of this review is to describe the physico-chemical properties of matcha, the specific requirements for tea cultivation and industrial processing. The quality of matcha mainly depends on the quality of fresh tea leaves, which is affected by preharvest factors including tea cultivar, shading treatment, and fertilization. Shading is the key measure to increase greenness, reduce bitterness and astringency, and enhance umami taste of matcha. The potential health benefits of matcha and the gastrointestinal fate of main phenolics in matcha are covered. The chemical compositions and bioactivities of fiber-bound phenolics in matcha and other plant materials are discussed. The fiber-bound phenolics are considered promising components which endow matcha with boosted bioavailability of phenolics and health benefits through modulating gut microbiota.
This study compares and clarifies the changes in intestinal flora resulting from the continuous consumption of two types of matcha. Healthy adults will consume two types of matcha tea for four weeks, ...and differences in the intestinal microflora before and after drinking will be compared. Gut microbiota will be identified using next-generation sequencing. Phylogenetic classification of the enterobacteria will be performed based on sequence similarities. The relative proportions of the classified enterobacteria to the total nucleotide sequences will be compared between the samples obtained from the two groups consuming different matcha. The continuous consumption of matcha may improve dysbiosis and prevent atherosclerosis. The effects may vary according to the type of matcha used. Trial registration: The study was registered with university hospital medical information network (UMIN) (UMIN000040303), and all participants gave their written informed consent. Registered 1 November 2020, https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000045982.
Matcha is gaining popularity around the globe, because of its worthy compositions and health benefits. This work proposed to predict free amino acids (FAA) and caffeine contents in matcha using a ...portable near-infrared (NIR) spectroscopy system combined with two different acquisition techniques (integrating sphere, IS; and fiber probe, FP) in comparison to a benchtop Fourier transform-NIR (FT-NIR) spectroscopy system. The prediction models were built using multi-variable selection algorithms such as synergy interval (Si), competitive adaptive reweighted sampling (CARS), and bootstrapping soft shrinkage (BOSS). Results in the current work showed that BOSS-PLS (BOSS-partial least squares) models yielded satisfactory results for both NIR spectroscopy types. In addition, the portable NIR-IS system has a prediction ability comparable to the benchtop FT-NIR, with coefficients of prediction (Rp) of 0.8920 and 0.8992 for FAA and caffeine, respectively. Consequently, the portable NIR-IS system has great compatibility for the rapid, accurate and on-site prediction of matcha compositions.
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•Free amino acids and caffeine of matcha were predicted using NIR.•Results between portable and benchtop NIR systems were compared.•Portable NIR-IS system has a prediction ability comparable to benchtop FT-NIR.•Model performance can be improved by variable selection methods.
Hyperspectral microscope imaging (HMI) technology as a novel approach was proposed to evaluate physical characteristics of matcha. Particle size distribution as one of the significant physical ...characteristics was investigated. Data fusion which integrated of textural features from images at 524 nm and key spectral features selected by competitive adaptive reweighed sampling (CARS) were as the raw data for modeling. Models were optimized by cross-validation. Results showed that the performance of models was improved with data fusion. The best ANN models with data fusion were achieved with Rp (correlation coefficient in prediction set) of 0.8020 for D10, 0.8414 for D20, 0.8238 for D30, 0.8124 for D40, 0.8058 for D50, 0.8157 for D60, 0.7643 for D70, 0.7360 for D80, and 0.6313 for D90, respectively. This work demonstrated that HMI technology as a rapid, accurate and high effective protocol has great potential in predicting particle size distribution in matcha powder.
•Particle size distribution in matcha was creatively assessed using HMI technology.•CARS selected characteristic spectral variables to simplify and enhance models.•Data fusion models combining image with spectra information can improve performance.
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•Combined LIBS with a novel sample preparation method to detect matcha adulteration.•Feature variables of the LIBS spectrum were selected by XGBoost.•The fusion model based on LIBS ...spectrum and image could achieve the best results.
Matcha adulteration is a critical issue in food production, which may reduce the effective components in matcha and have a detrimental effect on human health. Hence, laser-induced breakdown spectroscopy (LIBS) combined with chemometric methods was used to fast quantify the adulterant content. Two types of matcha adulteration, including mixing two grades of matcha (Fuding and Jiukeng) with barley seedling powder, were quantified with fusion of LIBS spectrum and ablation image. In addition, important features of spectrum and ablation image were extracted by extreme gradient boosting (XGBoost) and gray-level co-occurrence matrix (GLCM), respectively. Support vector machine regression models were established based on full spectrum, spectral features, and feature fusion. The models based on fusion of spectral and textural features achieved the best performance with R of 0.9046, RMSE of 0.12 for Fuding, and R of 0.9200, RMSE of 0.11 for Jiukeng. This study provides a fast approach for quantifying matcha adulteration.
The interest in the plant-derived healthy foods, nutraceuticals, functional foods and food supplements is increasing in recent times as potential agents in maintenance of health and the prevention ...and treatment of diseases. Matcha tea powder is obtained from the leaves of tea plant (Camellia sinensis (L.) Kuntze) grown under specific condition using about 90% shade. As compared to green tea, a hot water extract of tea leaves, matcha is consumed as a powder of whole leaves. Matcha powder is reported to have higher content of some bioactive components such as catechins, theanine and caffeine. In recent years, there is an increased market demand and consumption of matcha as a drink and as a component in various beverages, snacks and other food products.
In this review, the available scientific information of the chemical constituents and their analysis and biological activities were critically analyzed. These results may help to understand current status of research on matcha and the gaps which help to guide future research related to evidence based product formulations.
Various studies have reported the difference in bioactive compounds in matcha as compared to green tea and other tea formulations. The content and composition were mostly affected by the cultivation and processing techniques. Analysis of marketed samples in various countries have shown the variable content of the bioactive compounds. Thus, there is a need for proper standardization for maintaining the quality. Matcha as a whole, its extract and compounds have shown promising biological activities in in vitro and animal studies. However, comparatively only a few clinical studies are performed, which need future attention. There should also be more detailed studies regarding matcha-containing food products' formulation, quality control and biological activities.
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•Matcha tea powder is obtained from the leaves of tea plant grown under specific condition.•The food market demand of matcha is increasing rapidly in recent years.•Catechins, phenolic compounds, amino acids, and caffeine are major components.•Studies have shown its antioxidant, antianxiety and anti-stress activities among others.
Matcha green tea (MGT) is a natural product that is currently used as a dietary supplement and may have significant anti-cancer properties. However, the molecular mechanism(s) underpinning its ...potential health benefits remain largely unknown. Here, we used MCF7 cells (an ER(+) human breast cancer cell line) as a model system, to systematically dissect the effects of MGT at the cellular level, via i) metabolic phenotyping and ii) unbiased proteomics analysis. Our results indicate that MGT is indeed sufficient to inhibit the propagation of breast cancer stem cells (CSCs), with an IC-50 of ~0.2 mg/ml, in tissue culture. Interestingly, metabolic phenotyping revealed that treatment with MGT is sufficient to suppress both oxidative mitochondrial metabolism (OXPHOS) and glycolytic flux, shifting cancer cells towards a more quiescent metabolic state. Unbiased label-free proteomics analysis identified the specific mitochondrial proteins and glycolytic enzymes that were down-regulated by MGT treatment. Moreover, to discover the underlying signalling pathways involved in this metabolic shift, we subjected our proteomics data sets to bio-informatics interrogation via Ingenuity Pathway Analysis (IPA) software. Our results indicate that MGT strongly affected mTOR signalling, specifically down-regulating many components of the 40S ribosome. This raises the intriguing possibility that MGT can be used as inhibitor of mTOR, instead of chemical compounds, such as rapamycin. In addition, other key pathways were affected, including the anti-oxidant response, cell cycle regulation, as well as interleukin signalling. Our results are consistent with the idea that MGT may have significant therapeutic potential, by mediating the metabolic reprogramming of cancer cells.
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