Browsing by Author "Amarasena, S."

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    Factors Affecting on the Population Levels of Cigarette Beetle (Lasioderma serricorne)
    (Uva Wellassa University of Sri Lanka, 2016) Wijesinghe, D.T.D.; Alwis, L.M.H.R.; Weerawansha, A.N.R.; Amarasena, S.
    Ceylon tea as a beverage has been enjoyed by people all over the world for generations. It still has the value and interest as a beverage with many health benefits. Over a significant period of time, Sri Lankan tea industry has made progress in expanding the value added tea products. At present, Sri Lanka's value added tea exports include instant tea, tea bags, iced tea, flavored tea, green tea, herbal tea, ready to drink tea and organic tea. Herbal tea has become a major segment of value addition sector. Herbal teas draw higher market prices not only for tea's beneficial values but also the medicinal value of the herbs. These herbs are highly vulnerable to the attacks by different insect pests at storage conditions. Cigarette beetle is being identified as the most prominent storage pest in herbs warehouses. This experiment was therefore designed to identify the optimum storing condition that depress the population level of the cigarette beetle. Temperature, moisture and light wavelength were tested in this investigation. Three experiments were conducted separately to determine the effect of moisture (5%, 7%, 9%, 11%), temperature (21°C, 24°C, 27°C, 30°C) and light condition (Blue, Red, Pure white, Day light). Pheromone traps were used as the monitoring traps for to measure the population level. Sex ratio was determined by visual observation of chemically treated beetles through the stereomicroscope for their sex. The temperature level of 21°C and the moisture level of 5% helped to reduce the population level of the cigarette beetle. Red light condition recorded a significant reduction of population level than that of other tested wavelengths. Male to female sex ratio was identified as 1 to 4. Reduction of male insect population can lead to drastic reduction of whole insect population as females in the next generation would not have adequate males for mating. Longevity of the captured beetle was recorded up to 4 weeks. Thirty five percent of beetles were able to live up to 21 days while 25% survived up to 14 days. Keywords: Cigarette beetle, Herbal tea, Storage conditions
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    Value Addition to Black Tea by Supplying the Collected Volatile Compounds from Fermented Tea
    (Uva Wellassa University of Sri Lanka, 2012) Bandara, E.M.E.H.; Bandara, S.M.I.P.G.; Wijayaratne, L.K.W.; Amarasena, S.
    The tea plant, Camellia sinensis, is native to Southeast Asia. It is currently cultivated in more than thirty countries around the world, and is a popular beverage (Chaturvedula and Pi akash, 2011). A cup of infusion of made tea is completely different from that of fresh tea fl ushes in color, taste and aroma. These characteristics are developed during the manufacturing process once the tea flushes are harvested (Chaturvedula and Prakash, 2011). The volatile compounds present in fermented tea are lost during tea drying with exposure to direct heat (Zoysa et al., 2008). Resupply of those evaporated volatile compounds to black tea may increase the fresh and natural smell coming out of made tea, and thereby improve the smell of brewed tea liquor. Thus, it may enhance the consumer preference as well. The objectives of this research were: To collect the volatile compounds evaporated from fermented tea. To incorporate the collected volatile compounds again into black tea. To determine the smell, taste and colour of volatile-compound-incorporated black tea. To determine the shelf life of the developed black tea blend.