Synergy between curdlan and nanofibres of cellulose and chitin and its impact on the mechanical strength of oil-rich composite structures.

Abstract

With alternative meats trending, research on edible oil structuring for mimicking animal fat texture is gaining traction. However, many reported cases lack universal appeal, for they are structured by proteins and/or oleo-gelators based on steroidal or saturated fat, which may carry allergenic or cardiometabolic risks. Here, we report our discovery of synergy between curdlan (CG) and chitin (Chtn)/ cellulose (Shcel) nanofibres (NF) from small-to-large amplitude oscillatory shear experiments, and its applicative potential in fibre-based oil-rich composites as strong animal fat replacers. Some key findings are: (i) At optimised mass ratios, heat-set CG-Chtn (5:5) showed highly elastic character, while heat-set CG-ShCel (7:3) exhibited a more viscous but strain stiffening behaviour. (ii) CG-NF synergy led to derivative composites with high shear elastic modulus (G'₁) of ≥20 kPa (at ≤1 % strain), similar in the order of magnitude for springy cooked pork subcutaneous fat. (iii) To improve the compressive strength in the composites, the CG-NF binary phase could form an irregular mesh framework of extruded 1 mm-strands. (iv) By manoeuvring the viscosity and pliancy of the CG-ShCel binary phase, the compressive strength could be enhanced further. Put together, these findings offer reference value for formulating strong animal fat mimetics, toward more sustainable eating.