EFFECTS OF ENZYMATIC PRETREATMENT, TYPE AND RATIO OF CARRIER AGENTS ON THE QUALITY OF FREEZE-DRIED ROSEMARY (Rosmarinus officinalis L) POWDER

Abstract

The rise in busy lifestyles has led to a demand for healthy instant powders. An enzyme assisted extraction (EAE) method was found effective in extracting total phenolic contents (TPC) and antioxidants capacity (AC) from rosemary leaves. Freeze drying was identified as a suitable technique to preserve the TPC and AC while maintaining good physical properties. The objective of this research was to investigate the impact of enzymatic pretreatment, carrier agents, and their proportions on the quality of rosemary powder. Enzyme concentrations ranging from 0.1% to 2% and incubation temperatures from 30 to 60o C were adjusted to extract bioactive compounds, while carrier agents like maltodextrin, gum arabic, and their combinations in ratios of 20% to 40% were used during freeze-drying. Quality assessment of the resulting rosemary powder was based on parameters such as total phenolic contents, antioxidant capacity, moisture content, hygroscopicity, water solubility index, and bulk and tapped density. Increasing Viscozyme L concentration from 0.1% to 0.5% v/w improved effectiveness, with optimal results observed at 0.25% v/w. Higher incubation temperatures of 50 to 60o C resulted in increased total phenolic contents and antioxidant capacity values. The GA20 sample exhibited the highest TPC and AC values and acceptable physical properties.