Oxidative and physical stability, rheological properties and sensory characteristics of 'salad dressing' samples formulated with flaxseed oil and n-OSA starch

摘要

Flaxseed oil is one of the richest sources of Omega-3. This work was aimed at evaluating the physical qualities, sensory properties and the stability of a formulation for salad dressing characterized by a partial enrichment with flaxseed oil upon refrigerated storage. Samples were stabilized by n-OSA starch and sodium caseinate, and they were comparable with samples which had egg yolk only. All formulated dressings appeared as a weak gel-like structure with strong shear thinning behavior. The experimental data was fitted with the power-law model for all samples. The samples showed various degrees of oxidative stability after 90days of storage. Salad dressings containing n-OSA starch and sodium caseinate (samples 1-4) exhibited a small phase separation at the bottom of the tubes in the third month of storage, while no oiling-off was observed. In the presence of egg yolk (sample 5), a higher stability was observed with no phase separation or oiling-off. When there was 5% (w/w) flaxseed oil, a higher sensory quality was obtained in general. Increasing the percentage of flaxseed oil replacement in salad dressings and prolonging the storage time led to a decrease in the L factor. Salad dressings could be enriched aptly with flaxseed oil emulsions (while being stabilized by n-OSA starch and caseinate).