Tailoring cream by modifying the composition of the fat and interfacial proteins to modulate stirred milk gel texture

Abstract

The formulation-structure-texture relationship in stirred emulsion-filled food gels has rarely been analysed, let alone in realistic conditions. By studying thermal (calorimetry), structural (laser diffraction, confocal microscopy and mathematical morphology analysis) and textural (rheology and tribology) properties, this work advanced the understanding of this relationship in stirred gels made entirely from milk ingredients. Indeed, tailoring the fat composition (AMF, olein or stearin fractions) and interfacial proteins (native or heat-aggregated WPI) in cream resulted in different properties. Crystallisation of the fat droplets and probably their interactions (aggregation or partial coalescence), pore size, microgel size and the coarseness of the protein network in stirred milk gels were all modified by the cream formulation. The changes in properties led to different textures and lubrication behaviours of the stirred milk gels. The highlighted relationships between formulation, structure and texture are recapitulated in a concluding diagram.