No abstract

The objective of this study was to develop and characterize chitosan-ε-polycaprolactone (CHI/PCL) polymer blends with Tween 80 as a compatibilizer for application in packaging. The blends were produced by casting, with up to 10% (w/w) PCL in the CHI matrix. These blends were characterized in terms of their microstructure, chemical interactions, mechanical and thermal properties, solubility and water vapor permeability (WVP). The micrographs showed microsphere-like structures from the PCL in the continuous phase of CHI. Fourier transform infrared spectroscopy (FTIR) indicated a high interaction between CHI amino groups and PCL carbonyls, resulting in blends with greater ductility than the pure CHI film, thus providing greater flexibility. In the crystallinity analyses, the presence of PCL favored an increase in crystalline regions, limiting the passage of light. Given the results, blends are an alternative for application in multilayer systems and can be considered for use as a biodegradable fraction in food packaging.

Sulfiting agents are added to crustaceans products to prolong their shelf life. However, depending on the concentration, these agents can be toxic to consumers due to the presence of SO 2 . In this context, a colorimetric indicator label based on starch and iodine was developed to detect SO 2 in shrimp, showing whether the product is safe or not for consumers. The incorporation of iodine into the starch matrix resulted in labels with a smooth and homogeneous surface, and reduced water solubility from 9.26% to around 0.12%. In both in vitro and shrimp paste test, a visual detection response was observed in the label containing 0.02% of iodine when evaluated in the presence of 100 to 160 ppm of SO 2 , with ΔE* values greater than 5 (can be identifiable by the human eye). Therefore, the elaborated label showed potential as an economical and simple method to detect SO 2 concentration in shrimp-based foods.