Akademik Veri Yönetim Sistemi
I. ULUSLARARASI TÜRK DÜNYASI YEŞİL ENERJİ VE ÇEVRE BİLİMLERİ KONGRESİ, Astana, Kazakistan, 29 - 30 Nisan 2025, ss.315, (Özet Bildiri)
In tea production, generally the leaves and buds of the plant are used, while the remaining parts become waste. The stem and dust parts of tea, known as tea waste, are a rich source in terms of antioxidant capacity. In this study, the caffeine content in the stem and dust parts of tea was evaluated. An environmentally friendly method, ultrasonically assisted extraction (UAE), and natural deep eutectic solvents (NADES) were used for the extraction process. Initially, caffeine was extracted from tea waste using a NADES mixture (choline chloride–glycerol) through the UAE method, and the caffeine content in the obtained products was analyzed using an HPLC device. An experimental design was carried out for the extraction process; parameters such as NADES-water ratio, temperature, and duration were selected as independent variables. Optimization was conducted with 18 experiments based on these variables. The experimental design was obtained using Design Expert 11 Demo software. As a result of HPLC analysis, the highest caffeine content in the obtained extracts was determined to be 13,330 µg/g. Considering that the caffeine content in tea buds and leaves is typically between 20,000–30,000 µg/g, this study demonstrates that tea waste is a remarkably rich source for caffeine production. Based on the obtained data, the optimum extraction conditions were determined. The unique aspect of this study is the use of an environmentally friendly and non-toxic method to obtain active compounds with commercial potential from tea industry waste. Furthermore, the applied method offers an innovative and sustainable approach that can May lead to widespread effects in both the food and cosmetic industries.