Optimization of process parameters for spray drying of Tongkat Ali extract

Abstract

Tongkat Ali extract is well known for its aphrodisiac effect. Apart from that, Tongkat Ali extract also exhibits other therapeutic effects such as cytotoxic, antitumor, anti-pyretic and antimalarial activities. Most dried Tongkat Ali extracts produced in Malaysia are obtained using spray drying as compared to freeze drying because it is a cheaper process that produces dry particles of good quality. However, a major drawback of the manufacturing of Tongkat Ali is the low overall yield of dried Tongkat Ali, which is only about 3%. In this work, the focus was on the spray drying process. The influences of four variables (feed temperature, feed flow rate, air pressure, and air inlet temperature) on the efficiency of spray drying were investigated using response surface methodology (RSM). Based on the analysis of variance (ANOVA), the optimum conditions obtained were air inlet temperature of 160°C, feed temperature of 25°C, air pressure of 17.91 psi and feed flow rate of 4.86 ml/min. The efficiency of the spray drying process was 39.6%. The outcomes of this study have provided useful information on the effects of process parameters on the efficiency of the spray drying of Tongkat Ali extract.