Production of instant linden tea powder with spray dryer

As parallel to the development of consumer's coincides about the healthier lifestyle, tea market offers various healthier tea products. The purpose of this study was to optimize the spray drying parameters to produce instant linden tea together with the determination of the changes in infusion of flavonoids. The effect of infusion time on gallic acid, (+)-catechin, (-)-epicatechin, rutin, kaempferol and epimerization products were determined by high performance liquid chromatography. The optimum infusion time was determined as 45 minutes. It was revealed that, classical preparation of loose or bagged linden tea was not enough to extract all of the beneficial compounds. Optimization studies of spray drying were performed to obtain instant soluble linden tea powder with high quality. Feed rate, drying temperature and drying agent concentration were selected as independent variables in Box-Bhenken design. The responses used to compute the effects of independent factors were moisture content, yield, antioxidant capacity and total phenol content. The optimum spray drying parameters were determined as inlet temperature of 170 ⁰C, feed rate of 10 mL/min and maltodextrin concentration of %10 which yields antioxidant capacity as 34.39 TEAC, moisture content as 3.97 %, yield as 40.33 % and total phenol content as 2.18 GAEq. In conclusion, spray drying process performed at optimized conditions could be effectively used to obtain instant linden tea powder with a consistent desirable flavonoid distribution.