Comparing methods to produce fibrous material from zein.

Abstract

Three methods to produce fibrous material from zein, either as fibrous networks or individual protein fibres, were identified and developed for the purpose of providing a fibrous structure to whole-tissue meat analogues. These methods are: electrospinning, antisolvent precipitation of zein from ethanol using water and mechanical elongation of self-assembled zein networks. Analysis of the fibres was carried out using scanning electron microscopy, as well as texture profile analysis, moisture content and water holding capacity of the fibres within model meat analogue, tofu-style soy gels. Different advantages were identified for each of the three methods. Electrospinning produces individual fibres of the smallest scale, however the process used here was found to have a low throughput and be extremely inefficient. Antisolvent precipitation was the most rapid method, producing a web-like network, however the fibre formation was uncontrolled in terms of size and orientation. Finally, mechanical elongation allowed for great control over the formation of an oriented fibrous network, however advanced techniques to incorporate individual fibres into a matrix must be established. When incorporated into model meat analogue soy protein isolate gels, fibre quantity and orientation appeared to be the most determinant factors in creating statistically similar textures to chicken. The choice between fibre forming methods will ultimately depend on processing requirements and formulation of the eventual meat analogue product.