For the effective utilization of unexploited deep-water conger eels, Uroconger lepturus and Bathycongrus wallacei, a comparative study was conducted on their chemical composition, post-cooking physical properties, and sensory attributes, with the commercially harvested shallow-water species Conger myriaster and C. jordani. Both U. lepturus and B. wallacei showed no significant differences in the content of taste-active free amino acids compared to the edible species, while exhibiting higher taurine levels. Furthermore, despite undergoing significantly greater moisture loss during cooking, the unutilized conger eels were characterized by having a softer texture. Sensory evaluation revealed that the overall palatability of these unutilized species was comparable to that of the edible species under both boiling and grilling preparation methods. These results indicate that U. lepturus and B. wallacei are not merely well suited for use as substitutes for conventional edible species but constitute high-quality foodstuffs in their own right.

Freeze-thaw impregnation (FI) is a technique for the rapid impregnation of enzymes and other functional substances into food materials. This method enables the production of soft foods while retaining their original shape. In this study, two enzymes, Sumizyme BR and Peptidase R, were used to soften chicken breast meat. Gastric digestion was investigated using a gastric digestion simulator (GDS), an in vitro device that simulates human gastric peristalsis. Chicken breast treated with Peptidase R contained a greater amount of water-soluble protein than that treated with Sumizyme BR, without excessive softening. Both enzyme-treated meats exhibited digestion behavior distinct from the control. The control sample required more than 60 min to begin disintegration. In contrast, meat softened with Sumizyme BR disintegrated immediately, producing a higher proportion of small particles in the digesta. Consequently, water-soluble protein was rapidly released into the liquid phase of the gastric contents. Meat softened with Peptidase R did not disintegrate immediately and retained its original structure, resulting in a smaller initial release of water-soluble protein than the Sumizyme BR-softened meat. However, by the end of the GDS experiment, the peptidase R-treated meat released the largest overall amount of water-soluble protein into the liquid phase. These results suggest that the in vitro gastric digestion of enzyme-softened chicken breast is influenced by both the degree of mechanical disintegration of the sample and the extent of water-soluble protein formation within the tissue.

Methods for producing high-quality meat analogues have attracted considerable attention due to concerns related to the protein crisis and the need to reduce the environmental impact of rearing livestock. Compared to replicating flavor attributes, reproducing realistic food textures is considerably more challenging and has not yet been fully achieved. We developed a laser-based food 3D printer and demonstrated the fabrication of muscle fiber-like structures in model foods using dried egg-white powder. This approach enabled the replication of the textural characteristics of meat, such as the distinct mouthfeel experienced when biting parallel or perpendicular to muscle fibers. By controlling parameters such as fiber spacing and local structural design, it is expected that a range of meat textures can be reproduced using laser-assisted 3D printing technology.