Impact of combined ascorbic acid/CaCl2, hydrogen peroxide and ultraviolet light treatments on structure,rheological properties and texture of fresh-cut pear (William var.)

This work aimed to evaluate and correlate rheological properties (dynamic oscillatory, creep/recovery and double compression tests), texture (sensory evaluation) and structure (optical and transmission electron microscopy observations) of fresh-cut pear as affected by ascorbic acid/CaCl₂ dipping, hydrogen peroxide and short-wave ultraviolet light radiation (UV-C). All pear samples showed a solid behavior (G′ > G’’), but both dynamic moduli decreased in response to the treatments. For treated tissues, the instantaneous elastic (J₀) and the retarded (J₁, J₂) compliances increased, while the steady-state viscosity (η_N) and all mechanical parameters decreased. PLS regression models revealed that texture could be well explained by rheological properties. Deformability modulus (E_d) was positively correlated to sensory fracturability and hardness and negatively correlated to juiciness. J₀, J₁ and J₂ were negatively related to sensory hardness. Compression and creep parameters evidenced changes in structure (mainly rupture of membranes, degradation of middle lamella and cell walls) of surface tissues.