Objective To explore the applicability of different Zea mays L. varieties in the processing of functional beverages and analyze the impact of their physical and chemical properties on processing efficiency and product functional indicators, meanwhile, study and compare the retention effects of traditional hydrothermal sterilization and ultra-high-pressure sterilization techniques on the functional components and sensory quality of Zea mays L. juice. Methods The 4 kinds of Zea mays L. varieties, including 3 kinds of sweet Zea mays L. varieties and 1 kind of waxy Zea mays L. variety, were selected for evaluation. Key parameters such as juice yield, sugar content, protein, vitamin C, total phenols and dietary fiber were measured. Zea mays L. juice samples were subjected to sterilization treatments using water-heat sterilization and ultra-high-pressure sterilization. The effects of these treatments on microbial safety, sensory evaluation, and nutritional indicators were compared. Results Significant differences in nutritional and functional indicators were observed among the Zea mays L. varieties. The “Xuetian 7401” sweet Zea mays L. variety demonstrated remarkable advantages in juice yield, sugar content, and dietary fiber content, making it the optimal raw material. Compared to water-heat sterilization, ultra-high-pressure sterilization more effectively preserved soluble dietary fiber while minimizing sedimentation and sensory quality deterioration. A 15-minute ultra-high-pressure sterilization treatment ensured microbial safety while maximizing the retention of functional and sensory properties of the beverage. Conclusion The “Xuetian 7401” sweet Zea mays L. is an ideal raw material for developing high-quality functional Zea mays L. beverages. Ultra-high-pressure sterilization, with its low-temperature and non-thermal characteristics, is superior to traditional water-heat sterilization in preserving functional components and optimizing sensory attributes. This study provides a scientific reference for the selection of raw materials and process optimization for functional Zea mays L. beverages, contributing to enhanced market competitiveness and consumer acceptance.