Antioxidant water-resistant fish gelatin nanofibers: A comparative analysis of fructose and citric acid crosslinking and investigation of chlorogenic acid release kinetics

The use of bio-based and biodegradable electrospun mats encapsulating antioxidants is a promising strategy for creating innovative multi -layered food packaging materials, since the nanometric size of the fibers forming the mat maximizes the availability of the active compound. However, the development of water-resistant active electrospun mats using only non-toxic natural components remains a challenge. In this paper, water-resistant fish gelatin (FG) nanofibers incorporating chlorogenic acid (CGA), a natural antioxidant, were developed using either citric acid (CA) or fructose (F) as crosslinking agents. The CA-crosslinked fibers had a mean diameter of (200 +/- 50) nm and a solubility in cold water of (28 +/- 2)%, while F-crosslinked fibers were obtained with a mean diameter of (300 +/- 50) nm and a solubility of (5 +/- 3)%. CGA was quickly released when the mats were immersed in several food simulants, achieving equilibrium in less than 30 min for both materials. ABTS scavenging activity did not show significant differences (p > 0.05) regardless of the crosslinker, but DPPH activity was significantly higher (p < 0.05) in those samples crosslinked with CA. Physico-chemical properties of the developed materials were studied by FTIR, DSC, and TGA tests. Results demonstrate the release kinetics and antioxidant activity of electrospinning-fabricated water-resistant FG nanofibers.