Studies on supercritical fluid extraction and spray drying effect on the quality of instant tea of Mulberry leaves (Morus alba L.)

Abstract

Mulberry (Morus alba L.) is a Moraceae family plant that is often used for silkworm feeding. The value-added forms of mulberry leaves (Morus alba) significantly help to reduce blood sugar, cardiovascular diseases, inflammation levels, cholesterol and fight against heart disease. A process technology comprising supercritical fluid extraction (200 bar and 50 ºC), optimizing spray drying (inlet air temperature of 147 ºC and feed flow rate of 3 mL/min) and fluidized bed drying (45 ºC) was developed for production of instant tea from mulberry leaves. Physical, biochemical and reconstitution properties of the developed instant powder were determined. The powder had excellent handling and flow characteristics at low inlet air temperatures (130 °C). The increase in input air temperature resulted in a considerable improvement in reconstitution characteristics. The developed instant mulberry tea powder under optimized conditions showed Hausner ratio of 1.09, Carr's index of 9.35%, solubility of 97.51%, moisture content of 2.29%, protein of 1.32%, fat of 0.45% and energy of 403.94 kcal/100 g. The prepared instant mulberry tea had more acceptability in terms of sensory qualities compared to commercial mulberry tea.