| dc.description.abstract | The present study aimed to investigate the effects of inlet air temperatures and the
carrier concentration on the physicochemical and functional properties of green tea
powder during the process of spray-drying. Two independent variables including
inlet air temperatures (110°C, 130°C, 150°C) and mixtures of carrier agents (Gum
Arabic and gelatin) were studied. The concentrations of mixture carrier agent added
were 5%, 10%, 15% (w/v). The powder was obtained from the Lab Plant SD06 spray
dryer. The results revealed that moisture content (MC), solubility, scavenging
activity, total flavonoid content (TFC) and total catechin content (TCC) of samples
varied in the range of 2.86 – 10.59%, 59.24 – 76.51%, 20.47 – 42.92%, 2.59 – 7.08
mg RE/g and 0.95 – 2.41 mg CE/g, respectively. Color values of tea powder (L, a
and b) were 44.6 – 49.54, -17.83 to -12.47 and 19.57 – 31.39, respectively. The study
on temperatures showed that all of the analyzed parameters were significantly
affected by the shift in temperatures. However, the quality of the green tea powders
was also influenced by different concentrations of carriers. From the results of this
study, the powder produced by mixing with GA and gelatin at the concentration of
10% at 130°C retained the relatively low moisture content (5.87%); high levels of
scavenging activity (41.60%), TFC (6.86 mg RE/mg) and TCC (2.24 mg CE/mg)
with a high-water soluble ability (70.94%) as compared to the others, matching well
with quality requirements for an instant powder product. | en_US |
