affect the quality of the process or its products; what the Abstract-A problem for optimal control of a fed-batch optimal combination of settings for these significant fermentation process for production of yeast is formulated variables is, according to the goals posed on the process and solved. The problem is based on a criterion for maximum quality and the product quantity. There is a lack of methods production of biomass at the end of fermentation and on an for measuring of important variables, for modelling and unstructured mass balance biological model incorporating in . .. '.the kinetic coefficients the physiochemical variables parameter estimation and for optimisation and control considered as control inputs. A decomposition method for calculation. The stud S overcomin the constraints solution of the problem in two level calculation structure is highlighted above in the following way: developed on the basis of an augmented functional of 1) Unstructured model describing the behaviour of the Lagrange. A Matlab programme for calculation is written and biological variables identifying the dependencies applied for the fed-batch process for production of yeast. between physiochemical and biological variables is introduced in such a way: