Abstract: Abstract: A coarse cereal is one of the most important crops rich in nutrients. However, the frequently-occurred issues on food quality and safety have seriously endangered the trust in recent years, for example, the abuse of chemicals, heavy metals exceeding the standard, and harmful germs. Therefore, a traceability system is an urgent need for coarse cereals, in order to bridge the trust between farms and consumers, where the source of agricultural coarse foods can be rapidly traced through multi-party efficient collaboration. Most current traceability systems focus on recording data using bar or QR codes, radio frequency identification, and wireless sensor networks. But the tracing information is broken easily between upstream and downstream, leading to the blur transferred data, particularly on the long and scattered supply-chain of agricultural foods, including cultivation, processing, logistics, storage, and sales. Furthermore, the traditional traceability system cannot efficiently supervise the data records of each company, when quality and safety issues occur. As such, it is impossible to recall the problematic foods in time, much less to accurately locate the responsible party. Fortunately, blockchain technology can be utilized to integrate the distributed architecture, storage, and verification in the block, peer-to-peer network protocols, encryption, consensus mechanisms, identity authentication, and smart contracts. The data disclosure can also be used to enhance trust with fewer intermediate links. Therefore, this study aims to deal with the long supply-chain of coarse cereals, many trace entities, the differentiate share of data ledger, and the real-time monitoring of on-chain data. A novel traceability system was designed to implement the supervisable food products using the multi-chain architecture of blockchain and supply chain in coarse cereal. The forward and reverse traceability data was also collected ranging from the planting, processing, warehousing, transportation, and sales, using cameras, sensors, Beidou positioning devices, and IoT devices in real-time. Moreover, a systematic investigation was made on the business process and supervision characteristics of the supply-chain, as well as the full life cycle of coarse cereal. In addition, a new architecture of supervision-oriented multi-chain data storage was proposed for the actual production of coarse cereal. Specifically, the off-chain CouchDB state database was selected to store the key-value traceability data, particularly on the key-index instead of traversal query to improve the query efficiency. More importantly, a network access mechanism was designed using the regulatory authority, further to realize the collaborative supervision on- and off-chain through smart contracts. Correspondingly, blockchain technology was used to ensure the deep connection of various production factor resources with the real economy of coarse cereal. Anyway, the supply chain of coarse cereal integrated with the blockchain was utilized to strengthen the multi-party collaboration through mutual identity authentication, especially on data expansion, data sharing, and supervision. In terms of security, the average change rate of ciphertext in the enterprise network authorization diffusivity test was 82.53%, the average change rate of ciphertext in the enterprise network authorization correlation test was 82.39%, indicating higher security and less confusion. In terms of efficiency, the average time for consumers to query public traceability data was 0.415 s, and the average time for regulators to call cross-link port to query enterprise sensitive traceability data was 0.871 s. Furthermore, an actual traceability system was implemented to verify the model using Hyperledger Fabric for data privacy protection, data differentiation sharing, and the penetration supervision of traceability data, together with the real-time management, and control of traceability nodes. The in-depth mining was realized for the value of coarse cereal traceability big data, and sustainable development of the traced network. As such, farmers can receive professional or industrial policy guidance, whereas, companies can obtain the market trends and price conditions in real-time, and regulatory authorities can accurately control traceability data and transaction behavior. The finding can greatly improve the quality and safety of coarse cereal, production efficiency, and economic benefits.