Extending the Shelf‐Life of Wet Sweet Potato Starch Noodles Through Potassium Cinnamate: Antibacterial Mechanisms and Preservation Efficacy

ABSTRACT Wet sweet potato starch noodles are highly susceptible to microbial spoilage due to their high moisture content, leading to significant economic losses and food safety concerns. This study systematically investigated the bacterial inhibition mechanism of potassium cinnamate, a natural and eco‐friendly preservative, against dominant spoilage bacteria in wet sweet potato starch noodles. Pseudomonas aeruginosa and Trichosporon asahii were identified as the predominant spoilage species. Potassium cinnamate exhibited potent in vitro antimicrobial activity with minimum inhibitory concentrations (MICs) of 40 and 20 mg/mL, respectively. The antibacterial effect of potassium cinnamate was concentration‐dependent, and when combined with 0.2% citric acid, the shelf life of wet sweet potato starch noodles could extend to 90 days. Mechanistic analyses revealed that potassium cinnamate effectively inhibited microbial growth and biofilm formation by increasing cell membrane permeability, inducing protein leakage, and reducing cell surface hydrophobicity. Morphological alterations, including cell rupture and distortion, were directly visualized via scanning and transmission electron microscopy. These findings demonstrate that potassium cinnamate effectively disrupts membrane integrity and biofilm stability in spoilage microorganisms, providing a scientific basis for its potential application as a green preservative in the food industry.