Isolation and Identification of Spoilage Fungi in Potato Fresh Wet Vermicelli and Inhibition Effect of Different Fungicides on Spoilage Fungi

Fresh wet vermicelli is highly susceptible to microbial contamination during storage as a result of its high moisture content and rich nutrients, which leads to spoilage and deterioration. In addition to exerting a great impact on the quality of the product, this results in significant economic losses and potential food safety risks. This work aimed to identify spoilage microorganisms via traditional culturing methods and molecular biology techniques. The effects of environmental factors such as temperature and pH on the growth and development of the dominant spoilage fungi were investigated, and the inhibitory effects of both chemical (potassium sorbate) and natural antimicrobial agents (chitooligosaccharides, chitosan, tea polyphenols, citric acid, and ε-polylysine hydrochloride) were evaluated. The results indicated that <i>Penicillium crustosum</i> was the major spoilage microorganism in fresh wet vermicelli, whose optimal growth temperature and pH was 28 °C and 7, respectively. While conidial germination began at 7 h, hyphal formation was only observed after 12 h. Moreover, the findings suggest that both natural and chemical antimicrobial agents can effectively inhibit the growth of <i>P. crustosum,</i> with ε-polylysine hydrochloride being the strongest antimicrobial agent. Overall, the findings of this study provide a scientific foundation for improving the preservation of fresh wet vermicelli, which is of great significance for extending its shelf life and enhancing food safety.