Optimization of the static brewing technique for ready-to-drink Kangra orthodox green tea, sweetened with selected sweeteners

The central goal of this investigation is to optimize static brewing using response surface methodology for the preparation of static brew ready-to-drink Kangra orthodox green tea, while enhancing flavour and quality while incorporating selected sweeteners to satisfy consumer preferences and market requirements. In this study, the concentration of tea leaves (0.95–1%) and steeping time (7–16 h) were determined to be independent variables. The analysis of the statistical data exposed a significant consequence of extraction parameters on all responses. In static brewing, the optimal conditions were 1% w/w orthodox green tea leaves in 4 °C water, steeped for 14.40 h to maximize total phenolic content, antioxidants activity, a*, b* colour value and overall acceptability and to minimize pH, cream, tannins, caffeine and colour value L* of static brewing green tea. The predicted total phenolic content is 248.40 µL GAE/mL, antioxidants activity 92.73 mM TE/mL, a* − 4.17, b* 7.18 colour value and overall acceptability 8.33 and to minimize pH 4.69, cream 1.98%, tannins 19.32 µg TAE/mL, caffeine 33,180 mg/L and L* colour value 42.24 was under optimum static brewing extraction conditions. A balanced taste is achieved in the Kangra Orthodox ready-to-drink tea by combining sugar, honey, and xylitol, because these sweeteners all have varying nutritional and sensory properties. Sweetening agents (8–13° bx) were used to enhance the palatability of the ready-to-drink tea. Optimization of different sweeteners in static brew ready-to-drink Kangra orthodox tea based on sensory rating 10° bx in honey and sugar and xylitol (12° bx) based tea received the highest sensory rating. An innovative aspect of this study is the use of cold static brewing to produce ready-to-drink Kangra orthodox green tea at low temperatures (4 °C), which has demonstrated higher antioxidant activity and sensory appeal than traditional hot tea brewing methods.