International audienceIssued from cognitive sciences, computer sciences and applied mathematics, Knowledge (K) Engineering encompasses modelling and can be roughly defined by three steps: acquisition of available K, representation of acquired K and computational use of represented K for simulation, validation and optimisation purposes. These different steps are illustrated for various applications to food industry like the durum wheat chain, dough mixing for breadmaking, cheese ripening, based on specific approaches like decision trees and conceptual graphs, qualitative reasoning, Bayesian networks and optimisation under uncertainty and multi-criteria flexible querying, respectively. The application of such approaches opens prospects for th...