화학공학소재연구정보센터
Journal of Food Engineering, Vol.82, No.3, 276-283, 2007
Process technology for production of soluble tea powder
Instant tea is presently manufactured by spray/freeze drying of the concentrated brew of processed tea leaves/dust and the drawbacks of this method are inferior quality, high cost and energy. A novel technique has been developed for the production of instant/soluble tea powder from the expressed juice of green leaves. After plucking, the leaves are crushed and juice pressed out. The juice is then subjected to fermentation under specified conditions. The fermented juice is steamed, centrifuged and freeze-dried to get instant tea powder. The pressed leaf residue is subjected to fermentation and drying for preparation of tea granules. The instant tea produced is of good liquoring characteristics and various constituents are also in the acceptable range [Theaflavin (TF) to Thearubigin JR) ratio - 10.71 for instant tea (IT) and 12.12 for tea granules (TG), Caffeine content 40.4 mg/cup of IT and 96 mg per cup of TG]. The tea granules produced is comparable to CTC (crushing, tearing & curling) tea in quality and liquoring characteristics. There is considerable savings in the economy as the juice and residue are converted into value added products in this method. (C) 2007 Elsevier Ltd. All rights reserved.