Substitution of sesame and peanut defatted-meal milk with egg yolk and evaluation of the rheological and microstructural properties of low-cholesterol mayonnaise.

Peanut, sesame, and (peanut:sesame (1:1)) meal milk were used as the egg yolk substitute at the levels of 0%, 25%, 50%, 75%, and 100% in mayonnaise. Then, the rheological, textural (hardness, adhesive force, and adhesiveness), and microstructural properties of samples were evaluated on the first day after production. The oscillatory test indicated that all treatments had shear thinning flow behavior and in low-angular frequencies had higher elastic modulus than the viscous modulus (tan δ < 1), but in the P-S50 and P-S100, P75 and S75 in angular frequencies higher than 63 rad.s-1, tan δ was more than one (i.e. G″ > G') which indicated more viscous modulus (liquid-like flow behavior) than the elastic modulus (gel-like flow behavior). The optical microscopy confirmed that the oil particle size in blank, 25 and 50% of substitution was of smaller size, and the fat droplets had a monotonous and regular form. In 75 and 100% of substitution, the oil particle size was larger and more irregular than the other ones. Therefore, considering the emulsifying characteristic of oilseeds proteins, consumer health aspect (replacing meal protein with egg yolk in producing of low-cholesterol mayonnaise), and economic advantage aspect (reusing the oil-extraction factories by-products i.e., meal) using oilseed meal milk as an emulsifier agent in food industries especially emulsions is purposed.