Study on Soy-Protein Based Formulations for Fiber Production and Rheological Implications

摘要

Amongst efforts to mitigate the negative impacts of animal farming, one growing trend is substitution of meat with texturized food products derived from plant–based ingredients. Such meat analogues are more sustainably sourced, while being comparable in nutrition to traditional meat. However, the acceptability of plant – based meat analogues depends largely on how well they resemble to the organoleptic properties and nutrition of the meat. The current project proposes to emulate the textural properties through bottom–up reconstruction of the animal skeletal muscle structure, which is often missing in most commercially available meat analogues. This approach entails producing fine fibers as muscle fibers and assembling these fibers to mimic the hierarchical structure of muscles.The aim of this thesis is to produce fibers and understand the effects of ingredients and processing parameters on fiber forming process. In this work, thermal and rheological investigations were conducted on the formulations based on soy-protein isolates. Glycerol and three polysaccharides were used as additives to aid processing. The same formulations were spun into fibers using extrusion process with circular orifice dies. An attempt is made to relate the results from standardized tests to observed behavior during processing.Observations from extrusion trials revealed that glycerol imparted flexibility and polysaccharides increased the cohesiveness of the fibers. The final form of extrudate depends on the temperature used for extrusion, varying from pasty gels to elastic strands. A relation between extrudability of the formulations and continuous fiber formation with rheological parameter tan δ was observed. Furthermore, effects of temperature and ingredient concentration on complex viscosity were observed.