Food contamination causes a serious risk to public health and results in large financial losses when it occurs frequently. We consider the role of blockchain in food contamination and explore its implications for the strategic deployment of retailer contamination prevention effort. A supply chain with two suppliers and one retailer was proposed in this study. Supply chain participants may take out contamination prevention efforts to lessen the probability of food contamination. Among them, the retailer can trace the source of food contamination through the implementation of blockchain to reduce the loss of profits from the cascade threat. We developed a game-theoretic model to explore the strategic deployment of the retailer’s contamination prevention effort with and without blockchain and the impact of implementing blockchain on strategic deployment and food safety. The intuition is that implementing blockchain always benefits supply chain members. However, counterintuitively, the retailer may not be able to realize greater profits. Interestingly, for contamination-vulnerable food (CVF), having blockchain increases suppliers and the retailer collaboration. Collaboration becomes less likely for contamination-resistant food (CRF). Finally, it is important to note that the implementation of blockchain, for CVF, will reduce the food contamination probability. But for CRF, it may not.