Browsing by Author "Edirisinghe, E.N.U."
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Item Effects of Extraction of Tea with Tannase and Viscozyme Enzymes on Physiochemical and Sensory Properties of Cold Water Soluble Instant Tea(Uva Wellassa University of Sri Lanka, 2020) Jayasingha, J.A.K.K.; Perera, G.A.A.R.; Piyasena, K.G.N.P.; Edirisinghe, E.N.U.Due to the presence of Polyphenols and calcium haze develop and it affects the appeal of the beverage. Therefore, the effects of pre-treatment of tea with Tannase and Viscozyme enzymes on the physiochemical and organoleptic properties of cold-water-soluble instant black tea were investigated. Black tea samples (50 g each) were treated with five different levels (0.02%,0.04%,0.06%,0.08%,0.1%) of enzymes (dissolved in 150 mL of distilled water) separately at 40⁰ C for 40 minutes, Then, 150 mL of boiling water was added to each sample and extracts were obtained after brewing at 95⁰ C for 10 minutes. Extracts were centrifuged at 3500 rpm for five minutes at room temperature and the supernatants were obtained. Based on the physiochemical properties like Turbidity, polyphenol content, total soluble solids. Of supernatants, enzyme levels for pre-treatment were optimized. Secondly, black tea samples were treated with a combination of optimized enzyme levels following a similar procedure. Supernatants were freeze-dried and analyzed for physiochemical and sensory properties. Each experiment was repeated thrice. Physiochemical and sensory data were analyzed by Duncan Multiple Range test and Friedman test (p<0.05) respectively. The enzyme level of 0.06% which resulted in the lowest turbidity by both of the enzymes was selected as optimum. Revealing improvement in physiochemical properties, the sample treated with enzyme combination was significantly lower in turbidity (88.2±5.2) and higher in Theaflavin content (1.3±0.1%) and brightness (88.8±1.4) as compared to the control (99.4±5.5, 1.0±0.1% and 70.2±2.8 respectively). Further, it received higher ranks for sensory properties. Viscozyme and Tannase pre-treatment of tea extraction improve the quality of ColdWater-Soluble Instant Tea. Keywords: Instant black tea, Viscozyme, Tannase, HazeItem Effects of Viscozyme, Tannase and Protease Enzymes on Catechin and Caffeine Profiles of Cold-Water-Soluble Instant Black Tea(Uva Wellassa University of Sri Lanka, 2020) Sathsarani, W.M.I.; Perera, G.A.A.R.; Piyasena, K.G.N.P.; Edirisinghe, E.N.U.Different enzyme treatments have been invented to improve the clarity of cold-watersoluble instant black tea. This research was conducted to study the effects of different enzyme treatments on the catechin and caffeine contents of cold-water-soluble instant black tea. Samples of black tea extract were separately treated in triplicates with different combinations of Viscozyme, Tannase, and Protease enzymes at previously optimized level (0.3% wt/wt, based on tea solid in tea extract) at 40°C for 40 min. Samples were heated to 90°C and cooled to room temperature. Then they were centrifuged at 3500 rpm for 10 min and supernatants were analyzed for catechins and caffeine contents by High-Performance Liquid Chromatography. Data were subjected to Analysis of Variance and mean separation (p<0.05). Tannase can degallate gallated catechins releasing gallic acid and degallated catechins. Viscozyme hydrolyzes carbohydrates releasing constituents complexed with it. Therefore, samples treated with a combination of Tannase and Viscozyme contained a significantly higher amount of gallic acid (306.7±35.1 µg ml-1 ) than the other samples and this sample contained a significantly higher amount of Epigallocatechin (72.5±5.7 µg ml-1 ) and Epicatechin (89.2±8.4 µg ml-1 ) than the control and samples treated without Tannase. Moreover, samples treated with Tannase contained significantly higher amounts of total catechins and caffeine than the other samples. Catechins and caffeine positively affect the organoleptic properties of tea infusion. It can be concluded that treatment with a combination of Viscozyme and Tannase will enhance the catechins and caffeine contents of cold-water-soluble instant black tea. . Keywords: Cold-water- soluble instant black tea, Viscozyme, Tannase, Protease, CatechinsItem Evaluation of Changes in Polyphenol,Amino Acid and Catechins Content during Tea Wine Fermentation(Uva Wellassa University of Sri Lanka, 2021) Nisansala, H.M.S.; Perera, G.A.A.R.; Piyasena, K.G.N.P.; Edirisinghe, E.N.U.Tea Wine is an alcoholic beverage prepared by fermenting sugar enriched tea infusion with yeast (Saccharomyces cerevisiae). The Tea Research Institute of Sri Lanka developed this process with the intension of introducing diversified product of tea. Information on the changes of important tea constituents during tea wine fermentation will be useful for commercialization of this product. However, there is hardly any recently reported information on the changes in chemical constituent during tea wine fermentation. Polyphenols, catechins and amino acid mainly contribute to the characteristic organoleptic and therapeutic properties of tea. Therefore, the present study was undertaken to investigate changes in polyphenol, catechins and amino acid contents during tea wine fermentation. Filtered black tea infusion with 2% soluble solids (2 °Brix) was obtained and its Brix value was adjusted to 22 by adding sugar. Then this sugar enriched tea infusion was fermented with yeast in glass canisters fitted with fermentation trap in triplicate for six weeks. Changes in catechins, polyphenol and amino acid were investigated in weekly interval during the fermentation period. Total polyphenol contents of the samples were determined by Foilin Ciocalteu colorimetric method and catechins contents were determined by High-Performance Liquid Chromatography method whereas the total amino acid contents were determined by the Ninhydrin colorimetric method. Total polyphenol, total catechin and total amino acid contents of the initial sugar enriched tea infusion (in mg/100ml) were 425.21 16.00,30.67 0.24 and 4.46 1.11 respectively whereas contents of the these constituents in tea wine at the end of the six weeks of fermentation (in mg/100ml) were 307.06 7.77,28.86 0.74 and 3.89 0.06 respectively. Final product contained appreciable quantities of tea constituent known for therapeutic properties. Further, Tea wine contained significantly higher amount of total catechins (30.67 mg/100 mL) as compared to commercially available red wines (2.7 – 9.6 mg/100mL). Therefore, this rich chemical composition will be advantageous in marketing tea wine. Further, to make this investigation complete, studies on change in other important constituents such as caffeine, theaflavins and thearubins during tea wine fermentation will be required. Keywords: Amino Acid; Catechins; Fermentation; Polyphenols; Tea WineItem Evaluation of Changes in Theaflavin, Thearubigins, Caffeine and Alcohol Content during Tea Wine Fermentation(Uva Wellassa University of Sri Lanka, 2021) Arunodi, R.H.C.S.; Perera, G.A.A.R.; Piyasena, K.G.N.P.; Edirisinghe, E.N.U.Tea made from tender shoots of tea plant (Camellia sinensis) is renowned for its refreshing and health promoting properties. A process for manufacturing wine using tea extract was developed by the Tea Research Institute of Sri Lanka. As a diversified product, tea wine will broaden market for tea. Parties interested to commercialize this product are eager to know the chemical changes undergo during tea wine fermentation. Therefore, the present study was undertaken to investigate the changes in theaflavin, thearubigins, caffeine and alcohol contents during tea wine fermentation. Tea Infusion of 2°Brix was obtained by brewing black tea (Broken Orange Pekoe grade) with boiling water and it was enriched with sugar to form a 22 °Brix must. This prepared must was fermented with Saccharomyces cerevisiae in glass canisters fixed with fermentation traps for a period of six weeks. Chemical composition of fermenting wine was determined in weekly interval. Theaflavins ,and thearubigins contents were determined by (Roberts and Smith, (1963) method whereas caffeine and alcohol contents were determined by ISO 14502, (2005) and hydro meter methods respectively. This experiment was conducted in triplicate. Initial theaflavin (16.06±3.5 μg), thearubigins (809.23 ±39.11 μg) and caffeine (93.58±0.54 mg) contents per 100 mL of 22°Brix must decreased to 15.56 ±0.60 μg ,547.23 ±12.92 μg and 86.33±1.20 mg per 100 mL respectively at the end of the fermentation period. Alcohol content of the final product was 11.78% (volume by volume). Theaflavins and thearubigins are black tea polyphenols which contribute to much of physicochemical, organoleptic and therapeutic properties of tea. Further, caffeine is known as a central nervous system stimulant. Therefore, tea wine with its appreciable quantities of theaflavins, thearubigins and caffeine will be a better alternative to other types wines Keywords: Tea wine; Fermentation; Theaflavins; Thearubigins; Caffeine; Alcohol