Enhancement of resistant starch content in purple sweet potato flour (Ipomoea batatas (L.) Lam) using pullulanase enzyme

Ngô Lý Cẩm Tú; Vương Bảo Thy; Trần Ngọc Điệp; Nguyễn Ngọc Thiên Kim; Nguyễn Lê Tấn Thiện; Trần Hữu Thanh Huy; Bùi Thế Vinh

Issue: Số 17 - Tháng 6 - 2026 Hóa học - Công nghệ thực phẩm

Enhancement of resistant starch content in purple sweet potato flour (Ipomoea batatas (L.) Lam) using pullulanase enzyme

Published: July 20, 2026

Abstract

This study aims to determine optimal processing conditions for enhancing resistant starch (RS) content in purple sweet potato flour using pullulanase enzyme. The investigated parameters include pH (4.0 - 6.0), enzyme concentration (20 - 40 U/g dry starch), and hydrolysis time (8 - 24 hours). The results indicate that optimal conditions (pH 5.0, enzyme concentration 20 U/g, hydrolysis time 16 hours) yield an RS content of 28.19%, approximately double the initial level, with total starch content of 56.45%. Swelling capacity and apparent viscosity significantly decreased, reflecting the formation of thermally stable RS3 structure through amylose retrogradation. These findings provide a scientific basis for producing RS-enriched purple sweet potato flour with potential applications in functional foods for glycemic control.

Keywords

pullulanase enzyme purple sweet potato enhancement resistant starch

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