The functional properties of yogurts produced with exopolysaccharide (EPS) producing and non-producing S. thermophilus (ST) and L. delbruekii subsp. bulgaricus (LB) strains were screened, and correlations between the sensory and rheological properties were investigated. Yogurts were produced with cultures composed of one ST and one LB each and subjected to sensory texture evaluation and rheological oscillation and viscometry analyses. Choice of strains, especially ST, was found to affect the texture very much, and interactions between ST and LB also played an important role. EPS+ strains enhanced mouth thickness and ropiness, whereas EPS- strains resulted in the highest gel firmness. Creaminess could not be predicted directly from EPS content though EPS+ strains often secured a high creaminess. Fine correlations between mouth thickness and shear stress, between ropiness and hysteresis loop and between gel firmness and G~* were obtained, whereas the complex term creaminess was difficult to predictfrom the rheological measurements.
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