Spray drying of Eugenia dysenterica extract: effects of in-process parameters on product quality

ABSTRACT

A 2³ full factorial design was used to assess the impact of spraying air flow rate (30-50 L/min), drying air inlet temperature (90-150 ºC) and extract feed rate (4-6 g/min) on the quality of Eugenia dysenterica DC., Myrtaceae, spray-dried extracts. Response surface methodology (RSM) was applied to analyze the significance of the effects of process factors on product quality and to obtain fitted equations to predict dry powder properties. Powder yields were satisfactory, ranging from 34.64 to 63.92%. The dried products showed moisture contents and water activities below 5% and 0.5, respectively. The recuperation ratios of total polyphenols, tannins and flavonoids ranged from 88.66 to 99.07%, 70.38 to 81.87% and 74.51 to 98.68%, respectively. Additionally, in some conditions the parameters related to dry product’s flowability and compressibility varied over a range acceptable for pharmaceutical purposes. RSM proved that studied factors significantly affected most of the quality indicators at different levels. The spray drying technology is an attractive and promising alternative for the development of intermediate phytopharmaceutical products of E. dysenterica.