Strawberries rapidly deteriorate postharvest, necessitating effective measures to extend their shelf life. This study focused on developing an eco-friendly chitosan-based protective film for strawberry preservation. Strawberries were treated with a coating solution containing varying concentrations of hawthorn leaf extract (HLE) (0.4%, 0.7%, and 1.0%), 1.5% chitosan (CH), and 1% acetic acid. The results demonstrated that coating strawberry fruit with 1% CH-HLE notably delayed fruit spoilage. In-depth analysis revealed that, compared with the uncoated strawberry fruits, the 1% CH-HLE coating effectively reduced weight loss, the respiration intensity, malondialdehyde (MDA) levels, and superoxide anion (O₂^·-) production. Additionally, the coated strawberries exhibited improved firmness, total soluble solids (TSS), vitamin C (Vc) content, titratable acidity (TA), and total phenolic compound (TPC) content. The enzyme activities of superoxide dismutase (SOD) and catalase (CAT) in the CH-HLE-coated strawberries were greater than those in their uncoated counterparts. The application of a 1% CH-HLE coating successfully delayed spoilage and extend the shelf life of the strawberries by approximately 4-5 days. These findings suggest that CH-HLE has significant potential as a resource for protecting fruits and vegetables, offering an environmentally sustainable solution for postharvest preservation.

This work investigated the effects of calcium chloride (CaCl₂) as sodium replacement on the physicochemical properties of silver carp surimi. As NaCl replaced by 0.32% and 0.63% CaCl₂, surimi gels presented better textural properties, breaking force and rheological properties, while 0.95%, 1.27% and 1.58% CaCl₂ led to the deterioration of gel strength. With the addition of CaCl₂, water holding capacity (WHC) decreased significantly (p < .05), the T₂₃ relaxation time decreased and the proportion of T₂₃ increased. Compared with control, the sulphydryl content in surimi gel with 0.63% CaCl₂ increased by 23.61% and the solubility decreased by 17.31%. Furthermore, the Raman spectra data demonstrated that more β-sheet structures and random coils were induced in surimi gels prepared with CaCl₂. Then surimi with and without CaCl₂ was used as food-ink for three-dimensional (3D) printing, it indicated that surimi with 0.32% and 0.63% CaCl₂ could effectively improve the 3D printability.

The objective of this work was to investigate the effects of sodium replacement on the textural properties and water-holding capacity (WHC) of heat-set freshwater surimi gels. Potassium chloride and calcium chloride were chosen as salt substitutes. The surimi gels presented better water-holding capacity with potassium chloride than the treatments containing calcium chloride. Gel strength and rheological properties indicated that monovalent metal ions could improve surimi gel properties. The contents of chemical interactions, especially disulfide bonds, nondisulfide covalent bonds, and hydrophobic interactions of surimi gels, varied with the addition of salt type and concentration. Furthermore, microstructure observed from scanning electronic microscopy (SEM) demonstrated that surimi gels prepared with monovalent salt presented more compact and denser networks, while more aggregated particles existed in gels with calcium chloride.