We study the optimal control problem of a second order linear evolution equation defined in two-component composites with e-periodic disconnected inclusions of size e in presence of a jump of the solution on the interface that varies according to a parameter γ. In particular here the case $\gamma<1$ is analyzed. The optimal control theory, introduced by Lions (Optimal Control of System Governed by Partial Differential Equations, 1971), leads us to characterize the control as the solution of a set of equations, called optimality conditions. The main result of this paper proves that the optimal con...