Influence of different exopolysaccharide-producing strains on the physicochemical, sensory and syneresis characteristics of reduced-fat stirred yoghurt

Reduced-fat stirred yoghurts were prepared by using ropy and nonropy exopolysaccharide (EPS)-producing strains or nonexopolysaccharide-producing strains. Yoghurts were evaluated for pH, titrable acidity, acetaldehyde, whey separation, viscosity, EPS concentration, sensory and microbiological analyses. Determinations of these parameters were made at 1, 7, 14 and 21 days of storage. Reduced-fat yoghurts made with EPS+ strains exhibited lower syneresis and acetaldehyde contents, but higher viscosity than those made with the EPS- strain. Physico-chemical results correlated with the sensory results in that panellists scored the EPS+ yoghurts as having an overall better mouthfeel, but a worse. flavour than EPS- yoghurt.