ORCID

Abstract

Despite the growing interest in utilizing poultry processing by-products as sustainable sources of gelatine, the influence of extraction conditions on gelatine quality, structure, and functionality remains insufficiently understood. This study investigated the effect of acetic acid concentration on the yield, molecular characteristics, and structural-thermal properties of gelatin extracted from chicken feet and heads. Gelatine was extracted using 3 v/v% (CBBG3) and 5 v/v% (CBBG5) acetic acid. CBBG5 produced a higher extraction yield (13.2%) than CBBG3 (10.49%), indicating enhanced collagen solubilization at higher acid concentration. However, CBBG5 also showed higher ash content (4.45 w/w% vs. 2.40 w/w%) and more pronounced yellow-green coloration. Structural characterization using FTIR, SEM, SDS-PAGE, and DSC revealed notable differences between the samples. FTIR spectra showed characteristic gelatine amide bands, with CBBG3 exhibiting stronger amide I and II signals, suggesting better preservation of molecular structure. SEM analysis revealed a smoother, more compact morphology for CBBG3, whereas CBBG5 displayed a rougher and more irregular surface. SDS-PAGE showed higher molecular weights of the α1 and α2 chains in CBBG3 (156 and 130 kDa, respectively) than in CBBG5 (137.1 and 82.6 kDa), indicating lower molecular degradation. DSC further confirmed the superior thermal stability of CBBG3, which exhibited a higher glass transition temperature (26.97 °C) and transition enthalpy (2.688 J g-1). Although increasing acetic acid concentration improved gelatin yield, extraction with 3 v/v% acetic acid resulted in superior molecular organization, structural integrity, and thermal stability. These findings highlight the importance of optimizing extraction conditions to balance yield and quality and demonstrate the potential of chicken by-products as a sustainable source of high-quality gelatine for food, pharmaceutical, and biomedical applications.

Keywords

acetic acid concentration, chicken by-products, gelatine extraction, molecular weight distribution, structural characterization, sustainable biopolymers, thermal properties

Publication Date

2026-01-01

Publication Title

Frontiers in Chemistry

Volume

14

Deposit Date

2026-09-04

Funding

The author(s) declared that financial support was received for this work and/or its publication. This work was supported by Ongoing Research Funding Program, (ORF-2026-604), King Saud University, Riyadh, Saudi Arabia.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Download


Share

COinS