Although, neither higher biomass nor higher HePS concentrations were obtained through fed-batch fermentations using different feeding strategies (constant feeding rate and acidification-controlled feeding rate) as compared to similar batch fermentations, a high lactose pressure during acidification-controlled fed-batch fermentations revealed a higher stability of the high-molecular-mass HePS from S. thermophilus LY03 upon prolonged fermentation (Vaningelgem, Degeest, & De Vuyst, unpublished results). Additionally, a controlled feeding strategy may perhaps make it possible to produce tailormade HePS without the need of manipulating the producer strain genetically.