Effect of wheat gluten content and cooking method on the texture and flavor chemical compounds of plant-based meat analogues

The protein composition and cooking methods exert a significant influence on the structural and flavor profiles of plant-based meat analogues (PMAs). This study explores the effects of wheat gluten addition and cooking techniques on the characteristics of PMAs. In comparison with beef, the incorporation of gluten resulted in the induction of the transition from α-helix to β-sheet conformations, thereby enhancing the firmness and texture of the PMAs. Notably, the PMAs supplemented with 16 % gluten and subjected to stewing and roasting exhibited characteristics most analogous to those of beef. Following cooking, a total of 150 compounds were identified via gas chromatography-ion mobility spectrometry (GC-IMS), including 19 aldehydes, 31 alcohols, 33 lipids, 26 ketones, 24 heterocyclic compounds, 7 acids, and 10 other miscellaneous compounds. Specifically, 46 compounds were identified in the cooked PMAs, with lipids, aldehydes, furans, and pyrazines accounting for the majority. Representative compounds included 2-ethyl-6-methylpyrazine, 3-isobutyl-2-methoxypyrazine, and 2-pentylfuran. Following the stewing and roasting processes, a quantitative analysis was performed, which revealed a significant increase in the concentration of key flavor-active compounds in PMAs. These compounds included aldehydes (nonanal, benzaldehyde), ketones (1-penten-3-one, 5-methylfurfural), sulfur-containing compounds (methyl disulfide), and terpenoids (β-ocimene). These compounds collectively contribute to the characteristic flavor of cooked PMAs. These compounds primarily originated from the addition of aromatics and significantly masked the soy flavor. The principal distinction in flavor compounds between PMAs and beef was observed in the ketones. However, the presence of acetic acid butyl ester can serve as a primary marker for distinguishing PMAs from beef. These findings may serve as a reference for further research on the flavor formation of PMAs.