Structure of a new functional walnut oil-enriched mayonnaise

The aim of this work was to study the structure of a walnut oil-enriched mayonnaise, characterized by a high content of polyunsatured n-3 and n-6 fatty acids. Close packing structure of spherical and uniform oil droplets are observed in the control sample. When walnut oil is added, the droplets are polydisperse and the samples present a less close packing structure. The structure stability increases by increasing the rotation speed. Viscoelastic behaviour of the dressing sauce samples is affected by oil type, rotation speed and storage time. The increase in walnut oil content leads to the diameter dimensions oil droplets increase and consequently viscoelastic properties decrease. For each walnut oil content, the viscoelastic properties increase with increasing of rotational speed. Sensory profiles were affected only by oil type: at higher walnut oil content correspond more intense colour, bitterness, walnut odour and flavour; texture attributes change as a consequence of a different structure.