Rheological and thermal study of structured oils: avocado (Persea americana) and sacha inchi (Plukenetia volubilis L.) systems

J Food Sci Technol. 2019 Jan;56(1):321-329. doi: 10.1007/s13197-018-3492-4. Epub 2018 Dec 10.

Abstract

Rheological and thermal characterization was performed in emulsions formulated from avocado oil and sacha inchi oil structured with soy lecithin, glyceryl monostearate and shortening (palm oil). For oleogel formulations, a completely randomized factorial design was considered to study the effect of the type of emulsifier and the proportions of avocado and sacha inchi oils. The rheological results indicated pseudoplastic behavior with semisolid characteristics. Additionally, the phase change studies showed two endothermic events corresponding to melting points from - 20.15 to - 18.94 °C and from 40.25 to 61.04 °C. The formulation with a ratio of avocado oil to sacha inchi oil of 80/20 and prepared using glyceryl monostearate as an emulsifier was evaluated as the best treatment and had an increased consistency coefficient and an increased loss tangent (δ < 0.5).

Keywords: Emulsion; Oil; Phase transitions; Rheology.