The Global Matcha Research Library

Comprehensive assessment of matcha qualities and visualization of constituents using hyperspectral imaging technology.

… without compromising the integrity of the product. In this study, hyperspectral imaging technology (HSI) combined with machine learning methods enabled the first visual in situ assessment of matcha quality. The physicochemical …

Effects of Light Intensity and Spectral Composition on the Transcriptome Profiles of Leaves in Shade Grown Tea Plants (Camellia sinensis L.) and Regulatory Network of Flavonoid Biosynthesis.

… percentages, blue, yellow and red nets to alter the light intensity and light spectral composition in the fields. Flavonol glycosides are more sensitive to light intensity than catechins, with a reduction percentage of total flavonol …

Simultaneous quantification of chemical constituents in matcha with visible-near infrared hyperspectral imaging technology.

… multiple chemical constituents in matcha using visible-near infrared hyperspectral imaging (VNIR-HSI) technology. Regions of interest (ROIs) were first defined in order to calculate the representative mean spectrum of each sample. …

Assessment of matcha sensory quality using hyperspectral microscope imaging technology

Hyperspectral microscope imaging (HMI) technology coupled with chemometrics was attempted to mimic human panel test for estimating sensory quality of matcha in this study. The hypercubes from HMI system contained spatial and spectral …

Quantitative prediction and visualization of matcha color physicochemical indicators using hyperspectral microscope imaging technology

Detection of the Pigment Distribution of Stacked Matcha During Processing Based on Hyperspectral Imaging Technology

… pigments of stacked tea during processing. This paper presents the use of hyperspectral imaging technology (HSI), combined with machine learning algorithms, to detect chlorophyll a, chlorophyll b, and carotenoids in stacked matcha tea …

Monitoring of carotenoids changes during the matcha drying process using a portable developed spectral analytical system

… A total of 275 tea samples were obtained at various stages of drying for spectral acquisition and carotenoid analysis. After normalization preprocessing, bootstrapping soft shrinkage (BOSS), iteratively variable subset optimization …

Effects of Different Shading Treatments on the Biomass and Transcriptome Profiles of Tea Leaves (Camellia sinensis L.) and the Regulatory Effect on Phytohormone Biosynthesis.

Our previous study showed that colored net shading treatments had comparable effects on the reduction of bitter and astringent compounds such as flavonol glycosides in tea leaves, compared with black net shading treatment, whereas the…

Monitoring chlorophyll changes during Tencha processing using portable near-infrared spectroscopy.

… content by a portable near-infrared (NIR) spectrometer. The Tencha samples' spectral data were first preprocessed using various preprocessing techniques. Subsequently, iteratively variable subset optimization (IVSO), bootstrapping soft …

Application of visible-near infrared spectroscopy in tandem with multivariate analysis for the rapid evaluation of matcha physicochemical indicators.

… was firstly proposed for selecting the characteristic wavelengths from Vis-NIR spectra to build partial least squares (PLS) models. Results indicated that the ICPA-CARS-PLS models achieved satisfactory performance for the evaluation of …

Evaluation of matcha tea quality index using portable NIR spectroscopy coupled with chemometric algorithms.

… tea polyphenols and amino acids in order to index matcha tea quality. RESULTS Spectral data were preprocessed by standard normal variate (SNV), mean center (MC) and first‐order derivative (1 st D) tests. The data were then subjected to …

Multimodal Sensor Fusion for Non-Destructive Tea Quality Evaluation: Deep Learning-Enabled Methods, Applications, and Challenges.

… near- and mid-infrared spectroscopy, Raman and fluorescence spectroscopy, hyperspectral imaging, and electronic nose/electronic tongue systems, are discussed in relation to their ability to characterize appearance, chemical composition, …

Detection and classification of microplastics in green tea using SERS with gold nanoparticle substrates integrating chemometrics and deep learning.

… PET contamination in four green tea powder varieties across the 400–1650 cm -1 spectral range. To classify the samples, we compared two chemometric techniques—Partial Least Squares Discriminant Analysis (PLS-DA) and Support Vector Machine …

Identifying the Producer and Grade of Matcha Tea through Three-Dimensional Fluorescence Spectroscopy Analysis and Distance Discrimination.

… fluorescence spectroscopy features the advantage of obtaining emission spectra at different excitation wavelengths and providing more detailed information. This study established a simple method to discriminate both the producer …

Identification of the Geographical Origins of Matcha Using Three Spectroscopic Methods and Machine Learning

… analyzed using convolutional neural networks (CNNs), whereas NIR and FT-IR spectral data were analyzed using k-nearest neighbors (KNNs), random forest (RF), logistic regression (LR), and support vector machine (SVM) models. The …

Grade classification and protein content determination in matcha based on vis/nir

… classification and predict the protein content of matcha with near infrared spectra quickly, 240 samples of 3 matcha brands were collected for Vis/NIR spectroscopy on 325-1075 nm using a field spectroradiometer. The spectral data was …

Synchronous fluorescence spectroscopy combined with chemometrics for determination of total phenolic content and antioxidant activity in different tea types.

… were brewed at 80 °C and 96 °C for 2.5 to 30 min. Synchronous fluorescence spectra were recorded at different wavelength interval (Δλ) values for optimal models. AA and TPC of tea samples were determined by …

Fast nondestructive identification of steamed green tea powder adulterations in matcha by visible spectroscopy combined with chemometrics

… green tea powder’s concentration from 20% to 80% (w/w) were prepared and their spectra of 500–700 nm were acquired and applied for the qualitative classification and quantitative prediction. The principal component analysis–linear …