Synthetic biology brings new opportunities to food science， positioning food-grade chassis cells as the core platform for safe， efficient， and sustainable food production. This article reviews their selection and construction strategies， gene synthesis， and modular design， and analyzes applications in the precise synthesis of functional food factors and 'cell-factory foods'. It focuses on food safety challenges and solutions， including genetic， metabolic， and system-level safety control， regulatory standards， traceability systems， and the use of multi-omics in chassis design and safety assessment. It also outlines practical pathways from laboratory research to industrial implementation. Finally， it explores the potential of AI in chassis design optimization， food safety prediction， global regulatory alignment， and ethical governance， emphasizing AI as a key driver for the future transformation of the food industry. This article provides a systematic reference and forward-looking guidance for research and application of food-grade chassis cells.