Reducing antinutritional compounds in Amaranth using instant controlled pressure drop (DIC): A novel, sustainable processing approach

Abstract

Amaranth (Amaranthus hypochondriacus), a gluten-free pseudocereal rich in high-quality protein, holds significant promise for advancing global food and nutrition security. However, its broader adoption remains constrained by antinutritional factors such as tannins, phytates, oxalates, and lectins. This study explores the application of Instant Controlled Pressure Drop (DIC) technology, a thermo-mechanical, green processing technique, to mitigate these compounds in two amaranth varieties: Laura and Criollo. Through a central composite design varying steam pressure (0.1–0.4 MPa) and treatment time (10–90 s), we identified optimal DIC conditions (0.36 MPa, 22 s) that resulted in significant reductions of oxalates (up to 83 % in Laura, 69 % in Criollo), phytates (up to 11 % in Criollo), and effective lectin deactivation. Compared to conventional methods such as blanching, fermentation, or germination, DIC demonstrated superior, rapid, and multi-targeted mitigation of antinutrients while preserving thermolabile bioactive compounds. As a low-water, energy-efficient, and scalable process, DIC presents a promising alternative for enhancing the nutritional quality of amaranth. These findings underscore its potential for industrial integration and the development of functional, value-added food products that align with sustainable food innovation goals.