An oriented freezing strategy for fabricating fibrous structures of plant-based chicken analog

The increasing global demand for sustainable protein has driven significant research interest in plant-based meat analogs, which are expected to exhibit a fibrous structure resembling animal muscle tissue. In this study, we proposed a simple approach to fabricate plant-based chicken analogs using oriented freezing with a custom-designed apparatus. Pea, fava bean, and mung bean protein were applied at 10 wt% and 15 wt%, and the obtained analogs were systematically compared with chicken breast in structural, physicochemical properties, and oxidative stability. Macroscopic and microscopic analyses confirmed well-aligned fibrous networks in the analogs, comparable to the hierarchical structure of chicken breast. The analogs prepared by oriented freezing showed higher water-holding capacity and better thermal stability, with thermogravimetric profiles closely matching chicken breast. Furthermore, analogs formulated with a high protein weight percentage (15 wt%) exhibited low carbonyl level, indicating that oriented freezing could be an effective method to mitigate protein oxidation in plant-based meats. Among all formulations, the 15 wt% fava bean protein-based analog exhibited the best structural properties comparable to chicken breast, as revealed by appearance and protein secondary structure distribution. It is speculated that the unidirectional ice growth driven by the temperature gradient accounts for the phase separation and protein alignment into muscle-like fibers. This study demonstrates that oriented freezing is a promising novel strategy for generating fibrous structures in plant-based meats, offering potential advantages in terms of easy operation and gentle processing.