Thermal effect of spray drying process on the quality of ficus deltoidea extract

Abstract

Introduction: Spray dry is a single step of drying method to transform the fluid materials to dry particles. Common practice for producing the solid form is by using the freeze dry technique. However, the existing freeze dry process was associated with longer drying process, high maintenance and costly. Alternatively, researchers used spray drying during extraction process, yet, an elevated drying temperature applied may incur some effects on the quality and quantity of the extract. Therefore, the present study was aimed to investigate the thermal effect of spray drying process on the quality of spray dried Ficus deltoidea (F.deltoidea). Methods: The thermal effects of spray drying were identified at three different inlet air temperatures (160 oC, 191 oC and 220 oC) which are minimum, optimum and maximum of inlet air temperature, respectively. The Box-Behnken Design through response surface methodology was utilized to identify the optimum operating conditions at these temperatures. The quality of F. deltoidea in terms of yield, moisture content, marker compound (vitexin), total saponins, total protein and total polysaccharides were studied. Results: From the study, total saponins and polysaccharides exhibited better retentions during the spray drying process. Meanwhile, vitexin and total protein was found decreasing by 30% and 50% respectively, during the spray drying process. Conclusion: High operating of air inlet temperatures in spray drying process contribute to higher process yield, produce non-sticky particles with lower moisture contents compared to drying process at 160 oC.