Optimization of zein electrospun nanofibers for nisin delivery: A promising bacteriocin template for active packaging applications

This study aimed to evaluate how electrospinning parameters influence zein mean fiber diameter (MFD) and functionality with nisin incorporation, using Face Centered Composite Design (FCCD) and Response Surface Methodology (RSM) to assess four independent variables at three levels: zein concentration ( 225–265 g/L), applied voltage (10–30 kV), flow rate (1.0–4.0 mL/h), and tip-to-collector distance (10–20 cm). Model significance, accuracy, and predictive capability were confirmed by ANOVA, R 2 , adjusted R 2 , and predicted R 2 . Nisin-loaded fibers were also analyzed for tensile properties, hydrophobicity, and bioactivity. Zein concentration had the strongest effect on MFD (P < 0.0001), while voltage, flow rate, and tip-to-collector distance also showed significant influences (P < 0.05). Optimal conditions were 236 g/L zein, 10.1 kV voltage, 1.66 mL/h flow rate, and 19.88 cm tip-to-collector distance. Nisin release was slower at pH 6.3 than 3.8. Zein nanofibers containing 10 g nisin per kg zein showed antimicrobial activity against L. monocytogenes (12.22 mm inhibition zone) and 38.2% DPPH radical scavenging. Overall, electrospun zein fibers showed antimicrobial, antioxidant, and sustained-release properties for active food packaging. • Zein concentration was the main factor affecting nanofiber diameter. • Nisin-loaded fibers showed antimicrobial and antioxidant functions. • Sustained release and biodegradability support food packaging use.