The objective of this paper is the control of risks related to unforeseen changes in output demand at the end of a continuous-process supply chain. A dynamic blending approach has been developed to simultaneously define the optimal blends of inputs according to the order book and the inputs available in the blending area or which can be conveyed there from the mine. In the context of an uncertain universe, the risk of output stockout due to unpredictable demand is addressed by building up security stocks for some critical inputs along with the flexibility offered by dynamic blending. The optimization model for dynamic blending is described and a real-life example of the behavior of risk management through flexi-safety stocks is provided.