Defatted cashew nut shell starch as renewable polymeric material: Isolation and characterization

Starch attracts public attention as a replacement of fossil fuel in polymer industries because it is renewable, biodegradable and nontoxic. In this study, the isolation of starch from defatted cashew nut shell (CNS) using wet milling was reported. A product that contains 85.01 wt.% starch was recovered from the defatted CNS. Various analyses were performed on the starch to characterize its physicochemical properties. It was found that the starch obtained possesses high amylopectin content (75.35 wt.%), which supports the results of thermal analysis that proved the high crystallinity of starch. Morphological study of the starch showed that bonded resins were found attached to the starch granules. Due to high crystallinity, the presence of bonded resins and low cost, starch from defatted CNS can be considered as a prospective renewable material in polymer industries, with potential to compete with current feedstock such as potato and corn.