Cutting planes (also called cuts or valid inequalities) are constraints that cut off solutions from the LP relaxation but don't violate any integer feasible solution.
So these are redundant constraints in the sense that they are not required to define the set of feasible solution of the problem. Their role is to improve the dual bound and bring us closer to an optimal solution.
To illustrate the potential of cuts, we will revisit the Pastesian use case. Except that this time we will assume that there are multiple types of lasagnas and that a fixed cost (per type of lasagna) is charged when at least one lasagna is produced in a period.
Sample data is provided in the data/pastesian_data.xlsx worksheet and the formulation of this extended version of Pastesian is in the formulations/pastesian_fixed_cost_formulation.ipynb notebook.