Food loss and waste (FLW) constitute a major global concern with significant environmental and economic ramifications. A major cause of FLW is fungal contamination, leading to food spoilage. Here, we investigate the use of antimicrobial peptides (AMPs) as a new source for food preservatives to combat filamentous fungi and yeast contamination. Specifically, we focused on two model AMPs, BP100 and P-113, and their derivatives that were designed and synthesized as antifungal agents for food preservation. BP100 and P-113 were modified in order to enhance their efficacy. BP100 was modified by substituting its N-terminal lysine with tryptophan (i.e., BP100 K1W) to extend its hydrophobic α-helical side, and P-113 was extended by synthesizing the original sequence triplicated (i.e., P-113 Triple). The modified peptides demonstrated strong antifungal and antibacterial activities. Importantly, they showed low cytotoxicity and were digestible, indicating their safety for consumption. BP100 K1W was particularly effective in a hummus food matrix model, successfully inhibiting Penicillium expansum's growth and consequently extending the food's shelf life. Thus, this highlights its potential as an effective food preservative and paving the way for future research into peptide-based food preservation strategies.