Characterization of porous starch from edible canna (Canna edulis Kerr.) produced by enzymatic hydrolysis using thermostable α-amylase

Abstract

Porous starches are essential modified starches that have potential application as natural absorbents and contain abundant micro sized pores. Increasing interest is directed to utilizing the properties of porous starches in various starchy foods, such as Canna edulis Kerr. To date, no report about edible canna porous starch is available. Therefore, this study aimed to characterize the porous starch from edible canna produced by enzymatic hydrolysis using thermostable α-amylase. A starch suspension (25%, w/v) in phosphate buffer (0.1 M, pH 6.5) was added the thermostable α-amylase (100 U/g, 200 U/g and 300 U/g) and then incubated at 60 °C and 80 rpm for 8 h. The pellets were dried at 40 °C for 48 h. The SEM results displayed that the increase in enzyme concentration caused the formation of larger pores on the starch granule surface due to amylose degradation. FTIR and XRD analysis showed that enzymatic hydrolysis did not affect the crystalline structure of the edible canna porous starch. Furthermore, the edible canna porous starch exhibited high solubility and oil and water absorption capacity. Thus, the porous starch from C. edulis Kerr. could be used as a probiotic, flavoring, or drug delivery agent by microencapsulation.