The effects of hydrothermal treatment temperature and time on the textural characteristics of Lei bamboo shoots

Abstract

This study investigated the effects of hydrothermal treatment temperature and time on the textural characteristics of Lei bamboo (Phyllostachys violascens) shoots. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to analyse changes in chemical structure, crystallinity and microstructure. Mechanical properties, including modulus of rupture, modulus of elasticity, compressive strength and the bonding strength between bamboo shoot flesh and shell, were also measured. Results indicated that with increasing temperature and treatment duration, hemicellulose and cellulose components in both bamboo shoot shell and flesh degraded, primarily affecting the amorphous regions of cellulose, leading to increased relative crystallinity and alterations in the bamboo shoots' microstructure. The mechanical properties of the bamboo shoots generally decreased with increasing hydrothermal treatment intensity. Optimal softening and minimal mechanical properties were achieved at a hydrothermal treatment temperature of 100 °C for 30 min, with the bonding strength between bamboo shoot shell and flesh reaching a minimum of 3.21 N. These findings provide crucial data support for optimising bamboo shoot processing techniques and developing efficient peeling equipment.