Effective viscosity of lecithin solutions and fat emulsions of black soldier fly larvae with different lecithin content

Abstract

Fats and oils irrespective of their application field are usually used as emulsions — disperse systems consisting of two immiscible liquids stabilized by an emulsifier. One of the main indicators for emulsions is effective viscosity, which characterizes behavior of liquid in flow. This indicator is also important for optimization of production processes, application and storage of emulsions. It was found that fat of black soldier fly (Hermetia illucens) larvae is close to coconut and palm oil by its qualitative and quantitative composition, which makes it one of the promising alternative sources of fats for the industry. Based on this fact, the aim of the study was to determine effective viscosity of lecithin solutions and fat emulsions of black soldier fly larvae depending on the lecithin content of 0.5-2.5 weight%. It was found that consistency of the lecithin solutions increased when its concentration increased from 0.5 to 2 weight%. The lecithin solutions with concentrations of 1.0-2.0 weight% demonstrated weak pseudoplastic behavior and those with the lecithin content of 2.5 weight% dilettante. Emulsions with fat of black soldier fly larvae showed twofold lower consistency compared to the lecithin solutions of the same concentration and weak pseudoplastic behavior, which manifestation did not depend on the lecithin concentration.