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A long term study on the evaluation of shelf life of teas stored under normal conditions had been carried out. No decline in the quality parameter was noticed for a period of nine months after which there had been a mild but progressive decline in the level of quality constituents. Experiments on the effect of temperature on withering and fermentation have been carried out at our miniature CTC unit. Highest percentage of TF was observed when leaves were withered at 25o C and as the temperature increased, there had been a steady decline in the quality. The optimum temperature for fermentation was found to be between 25°C to 30o C. Time for Optimum fermentation got reduced with the increase in temperature but the quality of the end product deteriorated.
 A Comparative study on the keeping quality of teas stored in three different packing materials viz., Aluminum foil, LDPE and jute bags (lined with polythene) was conducted. Moisture absorption was higher in the teas stored in jute bags followed by LDPE bags. Aluminium foil pouches resisted moisture absorption and kept the tea well. Additionally, the teas were stored at warehouses at Cochin as well as at Coimbatore. The tea stored at Cochin absorbed more moisture than those stored at Coimbatore. Broken Orange Pekoe ( BOP ) and Pekoe dust ( PD ) were used in the study and both had the similar trend of moisture absorption.
 Biochemical studies on fermentation was carried out using the clone UPASI-3. Observations on the total polyphenols and theaflavins during fermentation revealed a progressive decline in the polyphenol level and an increase in the theaflavin till the optimum fermentation time of forty five minutes. The results on made tea analysis for the other quality constituents and various TF fractions also showed maximum quality with regard to the liquor characteristics at forty five minutes, which is the optimum fermentation time for UPASI-3.
 In connection with the studies on pacha taint in CTC teas, a methodology for the assay of lipase has been standardized. There was a progressive decline in lipase activity as the maturity of the shoot increased. Miniature level trials on the alleviation of pacha taint with the help of lipid degrading enzymes such as lipase, lipoxygenase, alcohol dehydrogenase and anti oxidants such as butylated hydroxy anisole(BHA) and ascorbic acid had been carried out with encouraging observations. A combination of lipase and lipoxygenase was found useful in decreasing the content of lipids and increasing the quality parameters. A study was undertaken to evaluate the impact of different methods of withering on lipid degradation. Maximum lipid degradation was observed in ultraviolet radiation and warm air withering.
Evaluation of flavors profile of Nilgiris tea had been carried out with orthodox tea sample of BOP grade procured from different agro climatic zones of the Nilgiris. Highest flavour index ( FI ) was noted in the month of January followed by October. The cool, dry weather could have the contributing factor the improvement in flavour.
A comparative study on the biochemical and quality parameters of NRC and RC teas showed that in addition to the better liquoring merit, non-RC teas had almost all the biochemical and quality constituents at a higher level. The increase had been significant.
 The impact of foliar application of certain nutrients such as SOP, potassium nitrate and calcium nitrate on the quality of tea had been studied. Foliar application of SOP at 2% level significantly increased the levels of polyphenols, catechins, theaflavins, thearubigins, briskness and color indices against control. Improvement was also noticed by tasters which substantiated the observations on biochemical parameters. Foliar application of potassium nitrate significantly increased the biochemical precursors such as polyphenols and catechins. Foliar application of Calcium nitrate had no significant effect on tea quality.
The effect of oxygen addition during fermentation on CTC black tea quality was evaluated. The made tea produced from the oxygen treated samples showed an overall improvement in the quality parameters which was substantiated by professional tasters. A chilled tea beverage with natural tea flavour has been attempted with encouraging results. Further work on stabilization of the product with preservatives and stabilizers is in progress. Experiments on freeze withering, flavor incorporation in made tea are under way. Extraction of polyphenols from black tea and tea waste is also being standardized.
 To study the influence of the quality of raw material on electrical power consumption and quality of CTC black tea, an experiment was conducted. Crop shoots of the clone UPASI –9 were segregated into three portions comprising 100% fine leaves, 75% fine leaves and 50% fine leaves. Two leaves and a bud , three leaves and a bud , soft banjies and single leaves were taken as fine leaf. Leaves above third leaf, cut and black leaves were considered as coarse leaves. Electrical power consumption was highest for the treatment involving 50% fine leaves and it decreased by 14% for 75% fine leaves and 24% for 100% fine leaves. The presence of coarse leaves besides deteriorating the quality increased the electrical consumption during manufacture and increased the cost of production.
The effect of pre-withering machine on the physical, chemical withering and quality parameters of black teas was studied. A minimum of two hours and 10 minutes withering duration can be reduced when the pre-withering machine was used and also there was a improvement in theaflavin levels. The improvement in flavour index also noticed when the machine used for withering.
Refinement of existing analytical techniques is also taken as a priority area of research. Methods have been developed for the assessment of ascorbic acid in crop shoots of tea, reducing power and antioxidant activity of black teas.
Besides the above mentioned works, division is also providing regular analytical service to the industry by way of analyzing made tea samples for PFA Act requirements. The laboratory has been accredited by NABL under ISO/IEC 17025.
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