The effect of key physicochemical properties, cell wall polysaccharides, and cell microstructure on the texture of Fuling Zhacai during pickling process

This study investigated the effect of physicochemical properties, cell wall components, enzyme activities, and structure of Zhacai on the texture during pickling. Results showed moisture and nitrite decreased while total acid increased. During pickling, WSP content increased while CSP and NSP contents decreased. β-Galactosidase (β-Gal) and polygalacturonase (PG) predominantly affected cell wall component content in Zhacai, followed by pectin methylesterase (PME). These changes were confirmed by Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) analyses. Overall, the firmness of Zhacai progressively worsens during pickling, mainly resulting from the breakdown of cell wall components and the destruction of its structural integrity induced by the pressing process, and the first pickling stages are critical periods for texture control. Findings from this study are conducive to maintaining the texture of Zhacai and can serve as an important theoretical and practical guide for industrial processing.