Enhancing Edible Bird Nest Cleaning Process by Immobilizing Cross‐Linked Enzyme Aggregates (CLEAs) of Keratinase

ABSTRACT Edible bird's nest (EBN) is a premium functional food prized for its nutritional and medicinal properties but conventionally cleaned through laborious and chemically intensive processes that compromise safety and quality. In this study, we developed a reusable cross‐linked enzyme aggregate (CLEA) form of keratinase as an eco‐efficient biocatalyst for EBN cleaning. The immobilized keratinase (keratinase‐CLEA) exhibited optimal performance at 50°C and pH 6, retaining up to 40% residual activity after five reuse cycles. Structural and morphological analyses (FTIR, FESEM) confirmed successful cross‐linking and stable aggregate formation, while kinetic evaluation revealed enhanced catalytic turnover ( V max = 9.77 mmol·L −1 ·min −1 ). When applied in EBN cleaning, keratinase‐CLEA reduced soaking time to 30 min while maintaining the nest's structural integrity and nutritional composition. Compared with free enzymes or conventional water cleaning, the reusable CLEA system provides a scalable, cost‐effective, and environmentally sustainable bioprocess, marking the first report demonstrating a recyclable immobilized enzyme platform for EBN purification. This work introduces a practical biocatalytic processing model applicable to high‐value animal‐derived food materials, supporting green manufacturing within the functional food industry.