| dc.description.abstract | The aim of this study is to investigate the appropriate conditions such as powderto-
water ratio (1:8 to 1:14(w/v)), enzyme concentration (0.5 to 2%(v/w)),
incubation and cooking time (0- 50 min for incubation and 60- 10min for cooking)
to hydrolyze starch into soluble dextrin from purple sweet potato by alphaamylase.
The appropriate hydrolysis conditions were determined as powder-towater
ratio of 1:10 during 50 min for incubation and 10 min for cooking and
concentration of alpha amylase of 1.5% to produce high reducing sugar content
and solubility. The purple sweet potato drink was prepared after treatment with
amylase using this condition and added with and without 0.1% (v/w) guar gum as
stabilizer and different amounts of water to evaluate color (L*, a* and b* value)
and viscosity (mPa.s). A quantitative descriptive test analysis method was applied
to define the sensory profile of these samples by instant sweet potato drink mixed
with guar gum with 30mL of water addition (viscosity is 70.50 ± 1.30 mPa.s and
lightness L* is 71.72 ± 0.85) was most preferred by panelists. As the results, the
instant drink was developed with powder to water ratio of 1:10 during 50 min for
incubation and 10 min for cooking and concentration of alpha amylase of 1.5%
with added 0.1% guar gum and 30ml of water to achieve the most appropriate
quality.
Keywords: Purple sweet potatoes, Ipomoea batatas (L.), alpha amylase, reducing
sugar, solubility, guar gum, viscosity, color measurement, sensory evaluation. | en_US |
