Exopolysaccharides from Lactococcus lactis affect manufacture, texture and sensory properties of concentrated acid milk gel suspensions (fresh cheese)

Abstract

Two exopolysaccharide (EPS) producing Lactococcus lactis strains that differed largely in their technofunctional properties (gel stiffness, ropiness) were used to relate their functionality in concentrated acid milk gel suspensions to the structural and macromolecular properties of the EPS. LL-1+ produced ropy and cell-bound EPS that contributed to acid milk gels with a higher gel stiffness, improved serum retention, and resulted in concentrated acid milk gel suspensions with smaller particles and a more ‘creamy’ texture compared with the non-ropy EPS from LL-2. From the basic structural and macromolecular analysis of the EPS it is concluded that mainly the higher hydrodynamic radius of the ropy EPS from LL-1+ is responsible for these features. The use of ropy and cell-bound EPS producing strains has, therefore, potential for the manufacture of low-fat fresh cheese with tailored functionality.