Abstract
Abstract
Recognizing the importance of cooking oil quality and the potential health risks associated with oxidation, this study developed an indirect-contact nanofiber-based system for detecting cooking oil oxidation. The effects of spinning parameters on sensor sensitivity were investigated. Eight nanofiber mats (MAT I–VIII) were fabricated using different needle sizes (21 G and 18 G), polymer concentrations (12% and 15%), and air pressures (0.5 and 2 MPa). Congo red was incorporated into polyacrylonitrile (PAN) nanofiber mats using a solution-blowing technique. The mats were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and colorimetric analysis. Sensor performance was evaluated during soybean oil heating at 180 ± 2 °C for 7 h. Peroxide value, para-anisidine value, total oxidation value, and acid value were monitored as oxidation indicators. After 7 h, peroxide value, para-anisidine value, and acid value increased to 14.55 meq O
2
/kg oil, 9.48, and 0.84 mg KOH/g, respectively. Nanofiber diameter strongly influenced oxidation detection. MATs VI–VIII, produced with the smaller 21 G needle, exhibited faster and more stable responses. MAT VIII (21 G, 15% PAN, 0.5 MPa) showed the most favorable sensitivity and response stability. The findings demonstrate the potential of PAN/Congo red nanofiber mats as an indirect-contact approach for visual monitoring of cooking oil oxidation.