Effect of processing steps on the quality of kenyan tea cultivated in Egypt
2012
Ali, F.A. | Badee, A.M.A. | Mikhail, W.Z.A. | Meleka, M.G.B.
Tea is a very popular drink in Egypt. We have studied the characteristics and effect of the processes steps of Kenyan tea cultivated ir1 Egypt and its effect on the quality. The obtained results show that during withering step,The essential oils increased from 0.01% in fresh leaves to 0.02% with yellow color, this illustrated that the formation of the essential oils was during withering step. The total amino acids increased slightly, from 1.47% in fresh leaves to 1.48/o after 12 hours of withering. The amino acids content was greatest at the stage of withering declining again at the stage of rolling. At rolling step, the total amino acids, for the two rolled types decreased to approximately 1%. The total polyphenols decreased during rolling due to oxidation reaction. The content of the total polyphenols was 15%. The essential oils were increased to become 0.03%. Rolling mincing produced the best product. At fermentation step, the effective components were determined and showed that total polyphenols were decreased as fermentation period increased; it was 12.50% after 2.5 hours and 11.50% after 3.5 hours fermentation. It showed also that the essential oils increased at fermentation step, it was 0.09% after 2.5 hours and 0.13% after 3.5 hours with dark yellow color. The amino acids content was 0.9%.The drying step, decreased the percentage of essential oils to 0.02% as a result of temperature effect, also the amino acids become 0.9% at 82�C and 50�C drying, and decreased to 0.6% at 88�C and 50�C drying.
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