Based on the PDCA concept, SNS has established a strict process quality monitoring system, such as characteristic sensory evaluation system, all-round quality monitoring plan (environment, raw and auxiliary materials, finished products, semi-finished products and water quality), and food safety and quality index monitoring plan (food additives, illegal additives, agricultural and animal residues and heavy metals). Irregularly carry out food traceability and protection drills to ensure the effective implementation of the quality management system and internal and external management requirements.