Green Tea Beverage Research Articles

Usability of Food Size Aids in Mobile Dietary Reporting Apps for Young Adults: Randomized Controlled Trial.

BackgroundYoung adults are more likely to use self-managed dietary reporting apps. However, there is scant research examining the user experience of different measurement approaches for mobile dietary reporting apps when dealing with a wide variety of food shapes and container sizes.ObjectiveField user experience testing was conducted under actual meal conditions to assess the accuracy, efficiency, and subjective reaction of three food portion measurement methods embedded in a developed mobile app. Key-in–based aid (KBA), commonly used in many current apps, relies on the user’s ability to key in volumes or weights. Photo-based aid (PBA) extends traditional assessment methods, allowing users to scroll, observe, and select a reduced-size image from a set of options. Gesture-based aid (GBA) is a new experimental approach in which the user makes finger movements on the screen to roughly describe food portion boundaries accompanied by a background reference.MethodsA group of 124 young adults aged 19 to 26 years was recruited for a head-to-head randomized comparison and divided into 3 groups: a KBA (n=42) control group and PBA (n=41) and GBA (n=41) experimental groups. In total, 3 meals (ie, breakfast, lunch, and dinner) were served in a university cafeteria. Participants were provided with 25 dishes and beverages for selection, with a variety of food shapes and containers that reflect everyday life conditions. The accuracy of and time spent on realistic interaction during food portion estimation and the subjective reaction of each aid were recorded and analyzed.ResultsParticipants in the KBA group provided the highest accuracy in terms of hash brown weight (P=.004) and outperformed PBA or GBA for many soft drinks in cups. PBA had the best results for a cylindrical hot dog (P<.001), irregularly shaped pork chop (P<.001), and green tea beverage (660 mL; P<.001). GBA outperformed PBA for most drinks, and GBA outperformed KBA for some vegetables. The GBA group spent significantly more time assessing food items than the KBA and PBA groups. For each aid, the overall subjective reaction based on the score of the System Usability Scale was not significantly different.ConclusionsExperimental results show that each aid had some distinguishing advantages. In terms of user acceptance, participants considered all 3 aids to be usable. Furthermore, users’ subjective opinions regarding measurement accuracy contradicted the empirical findings. Future work will consider the use of each aid based on food or container shape and integrate the various advantages of the 3 different aids for better results. Our findings on the use of portion size aids are based on realistic and diverse food items, providing a useful reference for future app improvement of an effective, evidence-based, and acceptable feature.Trial RegistrationInternational Standard Randomized Controlled Trial Registry ISRCTN36710750; http://www.controlled-trials.com/ISRCTN36710750.

Epigallocatechin-3-gallate in functional food development: From concept to reality

BackgroundEpigallocatechin-3-gallate (EGCG) is the most abundant and pharmaceutically active polyphenol in green tea. It shows diverse health-promoting effects, but due to its low oral bioavailability, its use in functional food development has been impeded. Over the years, the health-promoting effects of EGCG have been extensively reviewed; however, discussions of the possible use of EGCG in food development have been scant, even though copious ready-to-drink green tea beverages and nutritional supplements are available in the market. Scope and approachThe hopes and hypes involved in the use of EGCG in functional food development will be explored based on recent studies. Implications for future efforts to manipulate the properties of EGCG for food applications will be presented. Key findings and conclusionsRecent advances in technologies for structural modification and therapeutics delivery may enhance the food applications of EGCG. Despite this, justifications on the use of EGCG in functional food development should be seriously evaluated until a consensus is reached in terms of the safety and efficiency.

Simple and Sensitive Paper-based Colorimetric Biosensor for Determining Total Polyphenol Content of the Green Tea Beverages

A simple paper-based colorimetric biosensor based on immobilized tyrosinase and 3-methyl-2-benzothiazolinone hydrazone (MBTH) was developed for assessing total polyphenol content (TPC) of various green tea beverages. The patterned biosensing zone of the paperbased biosensor showed a sensitive response to catechin (a typical green tea polyphenol) by generating pink color adducts that can be captured for further color image analysis using a scanometric method. This color change can be connected to the TPC of the samples. The analytical performance of the biosensor in scanometric set-up was optimized. The biosensor showed a response time of 13 min in the linear range between 0.08-1.03 mM of catechin (r = 0.9979). The detection limit (LOD) of the biosensor was 0.071 mM while reproducibility was found at 3.11% RSD (relative standard deviation). TPC of green tea beverages was assessed by the biosensor, and the results were in accordance with the UV/Vis spectrophotometric method.

Thermostable Tannase from Aspergillus Niger and Its Application in the Enzymatic Extraction of Green Tea.

Tannase is widely used in tea beverage processing because of its ability to catalyze the hydrolysis of hydrolysable tannins or gallic acid esters and effectively improve the quality of tea extracts through enzymatic extraction. A new thermophilic tannase was cloned from Aspergillus niger FJ0118 and characterized. The tannase exhibited an optimal reaction temperature of 80 °C and retained 89.6% of the initial activity after incubation at 60 °C for 2 h. The enzymatic extraction of green tea at high temperature (70 °C) for a short time (40 min) was devised on the basis of the superior thermal stability of tannase. The enzymatic reaction significantly increased the total polyphenol content of green tea extract from 137 g·kg−1 to 291 g·kg−1. The enzymatic reaction effectively degraded the ester catechins into non-ester catechins compared with the water extraction method. Results suggested that the thermally stable tannase exhibited potential applications in the enzymatic extraction of green tea beverage.

Encapsulation of probiotics in whey protein isolate and modified huauzontle's starch: An approach to avoid fermentation and stabilize polyphenol compounds in a ready-to-drink probiotic green tea

A major challenge for the development of a ready-to-drink probiotic green tea beverage (RTD-PGT) is the undesired fermentation of the product by the probiotics and loss of polyphenolic compounds during shelf-life. Thus, the aim of this work was to evaluate the stability, cell survival and sensorial acceptability of a RTD-PGT formulated with Lactobacillus rhamnosus GG microencapsulated by spray drying in a matrix of whey protein isolate and modified huauzontle's starch, after refrigerated storage. Microcapsules contained 9.02 ± 0.3 log CFU/g, and for them to be incorporated to a RTD-PGT, ascorbic acid needed to be supplemented to prevent cellular loss. After 5 weeks of storage at 4 °C, the RTD-PGT showed a decrease of merely 0.44 log CFU/mL displaying final cell counts higher than the recommended 7 log CFU/mL, and no evidence of fermentation. Furthermore, 38.52 ± 0.72% of green tea polyphenols formed an insoluble complex most likely with at least one component of the microcapsules. No significant changes on the concentration of polyphenolic compounds or their antioxidant capacity were detected, and a minor change in color was quantified. The sensory shelf-life of the RTD-PGT was of at least 23 days at a 50% of consumer's rejection. In conclusion, a multipurpose encapsulation system was developed, generating a stable RTD-PGT.

Determination of caffeine content in tea beverages

Caffeine is the main component and characteristic indicator of tea beverages, and it is also a stimulant of the central nervous system. In this paper, the content of caffeine in 19 tea beverage samples in the market were determined by the ultraviolet spectrophotometry method, which was convenient, rapid, effective and low cost. The results showed that caffeine was detected in all samples as an inherent component of tea itself. The content of caffeine in green tea beverages, milk-flavored tea beverages and scented tea beverages was higher than that of black tea beverages and oolong tea beverages due to the different types of raw tea. Because of the difference in the source of raw tea and the difference in production process and formula, the caffeine content of beverages from different manufacturers of the same tea varieties was also significantly different, and there was great difference both in green tea beverages and in black tea beverages. The caffeine content in all samples met the requirements of Chinese national standard and did not exceed the prescribed limits set by the United States, Canada, Japan and other countries.

Natamycin photostability in acidified green tea beverage is dependent on mycosporine-like amino acids and epigallocatechin gallate interaction

It has been reported that mycosporine-like amino acids (MAA) have photoprotective effect in acidified green tea beverages containing natamycin as additive, but these results were far from conclusive. Therefore, the objective of this study was to further evaluate the photoprotective effect of MAA in acidified green tea stored in different lighting conditions. Reduced natamycin photostability was observed in beverages with pH 3.5 in relation to its natural pH (5.4), especially when stored under high light emitting diode (LED). Additionally, in pH 5.4 epigallocatechin gallate (EGCG) content reduced and natamycin degradation was also observed when beverages where expose to LED and fluorescent light. By adding MAA it was observed a sharp reduction of EGCG content, which led to faster natamycin degradation. When EGCG was added it was observed a better natamycin photoprotection, but it was not observed when MAA + EGCG were added together. To improve natamycin photoprotection it is necessary to increase EGCG content due to the reaction between MAA and EGCG in acidified green tea beverages.

Concentration of neonicotinoid insecticides and their metabolites in Japanese bottled green-tea beverages and their safety evaluation

Concentration of neonicotinoid insecticides and their metabolites in Japanese bottled green-tea beverages and their safety evaluation

A Excel for Accounting Assistance as the Solution for SME PT. JAB Surabaya

Several studies suggested that most of Small and Medium Enterprises (SMEs) only noted the amount of money received and expended, the amount of bought and sold goods, and the amount of accounts receivable/debt. However, the note is functioned as reminder but not supported with the format desired by the banks. Even though, they are still able to know the amount of final capital each year which is almost the same as if we took a note by using accounting system. Therefore, Small and Medium Enterprises (SMEs) are directed through assistance to start taking notes of its business activities in accordance with the Accounting Standards Entities of Micro, Small and Medium Enterprises (SAK EMKM) simply and completely as needed.&#x0D; Basically, the partner's problem in this assistance was due to the accounting administration of financial management at PT. JAB which is not properly arranged such as the determination of HPP. This SME produces coffee powder, chocolate and green tea beverages. It reaches income of Rp. 50.000.000,- per month with the total 3-5 employees and has carried out bookkeeping which is currently experiencing loss. It has already made an excel financial report but in determining HPP, the process costs are not taken into account so that this has no basis.&#x0D; The result of this assistance is the establishment of financial statement which is correct and appropriate in accordance with SAK EMKM. This study is finally able to solve the problem in determining the amount of HPP due to the lack of synchronization between the production data and accounting department. In addition, this study successfully minimizes errors in determining the amount of inventory which affects the error in determining HPP. The problem faced by every SME must be different so that we are expected to provide assistance in making financial reports.

Changes in phenolics and antioxidant capacity during short storage of ready-to-drink green tea (Camellia sinensis) beverage at commercial conditions

ABSTRACT The objective of this research was to evaluate the changes of phenolics and antioxidant capacity of a ready-to-drinkgreen tea beverage during short storage at commercial conditions. The total phenols (Folin-Ciocalteu), total catechins (4-dimethylaminocinnamaldehyde) and total non-catechins (difference between total phenols and total catechins) were evaluated as part of phenolic analysis, while antioxidant capacity was evaluated by using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical. At the beginning of the experiment, the levels of total phenols, total catechins and total non-catechins were 1220.69 ± 29.73, 636.94 ± 14.60and 584.75 ± 15.12 milligrams of catechin per liter of sample, respectively; these values decreased to 674.38 ± 26.52, 424.54 ± 11.29and 251.83 ± 37.81 milligrams of catechin per liter of sample, respectively, after nine days of storage. The losses of phenolics at the final day of the experiment were 44.67% in total phenols, 33.40% in total catechins and 56.93% in total non-catechins. The initial values of the DPPH antioxidant capacity were 3116.43 ± 90.91 micromoles oftrolox equivalents per liter of sample and 66.09 ± 1.82 percentage of radical scavenging. These values decreased to 1288.86 ± 70.71 micromoles of trolox equivalents per liter of sample and 31.90 ± 2.44percentage of radical scavenging after nine days of storage, which means a loss of 58.62% and 53.24%, respectively. The data obtained in this work give information to the ready-to-drink green tea consumers, manufacturers and food researchers about loss of compounds with beneficial health effects during short storage of greentea at commercial conditions.

Green tea extract prevents the development of nonalcoholic liver steatosis in rats fed a high-fat diet.

Green tea contains many polyphenolic constitutes, which might prevent non-alcoholic fatty liver disease (NAFLD). We aimed to investigate whether green tea extract (GTE) given at doses reflecting habitual consumption of green tea beverages prevents development of NAFLD in rats fed a high-fat diet (HFD). Twenty-four male Wistar rats were randomly divided into four equal groups (two study and two control groups). The study groups received a HFD (approximately 50% energy from fat), enriched with 1.1% and 2.0% GTE, respectively, for a total of 56 days. The control groups were fed a HFD alone and normal standardised diet (low-fat diet), respectively, for the same period of time. The percentage of hepatocytes affected by steatosis in the HFD group (median [1st-3rd quartile]: 25% [12-34%]) was higher (p < 0.033 and p < 0.050, respectively) than in the HFD-2.0%GTE group (9% [3-18%]) and normal diet group (10% [5-18%]). No significant differences were observed for the group consuming HFD-1.1%GTE, in which intermediate results were observed (15% [4-30%]). This finding points towards the hepatoprotective potential of GTE in preventing dietary-induced liver steatosis. In view of the increasing incidence of overweight and obesity a simple and cheap dietary modification, such as GTE supplementation, could prove to be useful clinically.

Optimizing the extraction parameters of epigallocatechin gallate using conventional hot water and ultrasound assisted methods from green tea

Epigallocatechin gallate (EGCG) is the main polyphenol present in green tea and is also known to possess various beneficial health effects. Extractions of EGCG, epigallocatechin (EGC), epicatechin gallate (ECG), and epicatechin (EC) from green tea were investigated by both conventional hot water extraction and ultrasound assisted extraction (UAE) with water and ethanol. Response Surface Methodology was used in order to optimize the extraction conditions for obtaining maximum amount of EGCG in the extracts. Pilot scale conventional hot water extraction and UAE with water in continuous flow mode were also conducted for industrial use. UAE with ethanol was significantly (p<0.05) efficient to extract more EGCG, EGC, ECG, and EC than conventional hot water extraction and UAE with water. At optimum conditions, almost 100 and 50% more EGCG content was obtained in UAE with ethanol than conventional hot water extraction and UAE with water, respectively. The optimal conditions for UAE of EGCG with ethanol were 66.53°C, 43.75min and, 67.81% ethanol. Conventional hot water extraction can easily be scaled up to a pilot scale and can be used for green tea beverage production. UAE should also be scaled up to a pilot scale by an efficient design either using an ultrasound probe in a larger volume continuously or ultrasound probes on each side of the extractor tank with an agitation system.

Development of an objective measure of quality and commercial value of Japanese-styled green tea (Camellia L. sinensis): the Quality Index Tool.

A novel approach to evaluate the commercial value of green tea products is explored in this paper. The green tea Quality Index Tool (QI-Tool) is based on high performance liquid chromatography (HPLC), capable of identifying and understanding the constituents that are important to create superior consumer and commercially valuable green tea beverages in the Japanese-style. This tool will allow producers to better identify a product's potential value within the various levels of green tea retail quality structure. Via the quantification of theanine, caffeine and the catechins: epicatechin (EC), epicatechin gallate (ECG), epigallocatchin (EGC), epigallocatechin gallate (EGCG) and gallocatechin gallate (GCG) within a green tea beverage, the QI-Tool provides categorisation of a product against the green tea market retail competitive set. This allows a better understanding of the product's potential commercial value, as well as a comparison to other products within that market category. The QI-Tool is an alternative and promising method for objectively evaluating commercial value of green tea products using HPLC analysis.

The effect of tea consumption on the steroid profile.

Green tea (GT), along with its flavonol epigallocatechin-3-gallate (EGCG), has shown to inhibit the UGT2B17 isoenzyme, which is highly involved in the glucuronidation of testosterone (T) and its metabolites. Since the steroid profile (SP) is composed of urinary concentrations of T and related metabolites excreted in both the free and the glucuronide fractions, GT consumption could alter the SP, leading to misunderstanding in doping controls. The aim of the present work was to study the effect of GT consumption on the SP. This study was performed with 29 male volunteers, which could be classified in 2 arms depending on their T/E values (0.12±0.02, n=12; 1.64±0.90, n=17). The clinical protocol was designed to evaluate the effect of GT administration on the SP biomarkers. Participants were asked to consume GT with a high content of EGCG for 7days (5 GT beverages along the whole day for days 1-6 and 9 GT beverages on day 7, corresponding to 520 and 936mg/day of EGCG, respectively). Urine samples were collected before and during GT consumption at different time periods. The SP was measured using gas chromatography-mass spectrometry. The excretion rates of the SP metabolites did not change after GT consumption. Moreover, the individual evaluation of the subject's steroidal biological passport resulted in normal sequences. The results obtained show that GT consumption does not distort the establishment of normal ranges of SP parameters. Therefore, GT consumption does not need to be considered a confounding factor in the SP evaluation.

Quantification of ascorbyl adducts of epigallocatechin gallate and gallocatechin gallate in bottled tea beverages

Catechins are the major bioactive compounds existing in tea leaves (Camellia sinensis). Dehydroascorbic acid is (DHAA) a reactive dicarbonyl species and previous studies have demonstrated that catechins could effectively trap DHAA to form ascorbyl adducts of catechins, especially epigallocatechin gallate (EGCG). Since catechins in the aqueous solution are unstable due to their structural features, ascorbic acid (AA) is usually added to bottled tea beverages to protect catechins. However, whether ascorbyl adducts of catechins are formed in bottled tea beverages remains unclear. In this study, formation of ascorbyl adducts of EGCG increased along with increased incubation time when EGCG and AA were dissolved in the aqueous solution. Next, 6C-DHAA-EGCG and 8C-DHAA-EGCG were detected in both green tea and oolong tea beverages, and their concentrations ranged from 0.23 to 1.95 µM and 0.28 to 1.97 µM, respectively. Furthermore, an 8C-ascorbyl adduct derived from gallocatechin gallate was also found in some tea beverages.

UV-C Irradiation on the Quality of Green Tea: Effect on Catechins, Antioxidant Activity, and Cytotoxicity.

Short wavelength ultraviolet (UV-C) irradiation is a nonthermal processing technique that is a possible alternative to the heat pasteurization of tea beverages. This study investigated the effect of UV-C irradiation on the antioxidant concentration of green tea and analyzed cytotoxicity of irradiated a green tea beverage using a novel continuous flow-through UV system. The results demonstrated that the UV-C irradiation did not significantly deplete catechins or produce cytotoxic byproducts.

The Nutraceutical Impact of Polyphenolic Composition in Commonly Consumed Green Tea, Green Coffee and Red Wine Beverages: A Review

The Nutraceutical Impact of Polyphenolic Composition in Commonly Consumed Green Tea, Green Coffee and Red Wine Beverages: A Review

The Nutraceutical Impact of Polyphenolic Composition in Commonly Consumed Green Tea, Green Coffee and Red Wine Beverages: A Review

The Nutraceutical Impact of Polyphenolic Composition in Commonly Consumed Green Tea, Green Coffee and Red Wine Beverages: A Review

Influences of Product Temperature on Emotional Responses to, and Sensory Attributes of, Coffee and Green Tea Beverages

Coffee and green tea are popular beverages consumed at both hot and cold temperatures. When people consume hot beverages concurrently with other activities, they may experience at different temperatures over the period of consumption. However, there has been limited research investigating the effects of product temperatures on emotional responses and sensory attributes of beverages. This study aimed to determine whether emotional responses to, and sensory attributes of, brewed coffee and green tea vary as a function of sample temperature. Using a check-all-that-apply (CATA) method, 157 participants (79 for coffee and 78 for green tea) were asked to evaluate either coffee or green tea samples served at cold (5°C), ambient (25°C), and hot (65°C) temperatures with respect to emotional responses and sensory attributes. The results showed that sample temperature could have significant influences on emotional responses to, and sensory attributes of, coffee and green tea samples. More specifically, 6 and 18 sensory attributes of coffee and green tea samples, respectively, significantly differed with sample temperature. Beverage samples evaluated at 65°C were characterized, regardless of activation/arousal level, by positive emotional responses terms and favorable sensory attributes. While beverages evaluated at 25°C were associated more with negative emotional responses with low activation/arousal, those evaluated at 5°C were more frequently characterized as having negative emotional responses with high activation/arousal. Sensory and emotional drivers of liking for both coffee and green tea differed both with sample temperature and gender. While both emotional responses and sensory attributes were identified as drivers of liking among females, only emotional responses were identified as drivers of liking among males. In conclusion, this study provides empirical evidence that both emotional responses to, and sensory attributes of, coffee and green tea beverages can vary with sample temperatures. To provide a better understanding of product characteristics, emotional responses to, and sensory attributes of, coffee or green tea beverages should be tested over a wider range of product temperatures.

Determination of Amounts of Catechin and Caffeine in Green Tea Beverages

Determination of Amounts of Catechin and Caffeine in Green Tea Beverages