Impact of vacuum treatment on multi-layered structure and physicochemical properties of reconstituted fish steaks: Specific effects of air distribution within meat-air systems

Abstract

The air distribution within the meat-air systems was regulated through vacuum treatment, followed by an investigation into effects of vacuum time on multi-layered structure and physicochemical properties of reconstituted fish steaks made from minced muscle. In the absence of vacuum treatment, an inferior multi-layered structure with many circular holes was observed. Appropriate vacuum treatment (25–75 s) effectively eliminated air bubbles responsible for these circular holes while retaining those that contribute to the stratified phase, thereby facilitating the development of a superior multi-layered structure. Conversely, excessive vacuum treatment (≥99 s) would further promote the outflow of stratified phases from the food system, leading to blurring or even disappearance of multi-layered structure. Moreover, appropriate vacuum treatment enhanced the multi-layered structure by promoting conversion from random coil into β-sheet. However, by promoting migration of free water to an immobile state and conversion of β-sheet to random coil, excessive vacuum treatment could improve water holding capacity to some extent, but lead to the weakening of multi-layered structures. In conclusion, judicious application of vacuum treatment is advantageous for regulating stratified phases within complex multi-layered structure, thereby preparing superior anisotropic reconstituted fish steaks. The findings of this study are conducive to potential applications in the food industry for improving low-value fish utilization and the development of novel reconstituted meat products.