Preparation and characterization of intelligent packaging labels based on pea starch, κ-carrageenan and black raspberry extract for monitoring freshness of pork

Intelligent biodegradable packaging has gained significant attention recently due to its great potential for food freshness monitoring. In this study, we developed intelligent labels using pea starch (PS), κ-carrageenan (KC) and black raspberry extract (BRE) and evaluated their physicochemical properties and effectiveness in pork freshness monitoring. Incorporation of KC significantly decreased tensile strength (TS) (33.43 to 19.84 MPa) and increased elongation at break (EAB) (6.26 to 7.41 %) and water vapor permeability (WVP) (2.11 to 2.48 × 10⁻⁹ g m⁻¹ s⁻¹ Pa⁻¹) of PS label. Incorporation of BRE significantly decreased WVP (2.48 to 1.96 × 10⁻⁹ g m⁻¹ s⁻¹ Pa⁻¹) and increased TS (19.84 to 29.68 MPa) and EAB (7.41 to 11.09 %) of PS-KC label. PS-KC-BRE labels showed increased light barrier performance, thermal stability, antioxidant activity, pH and ammonia sensitivities, and significant visible color change as pH indicators. Findings suggest PS-KC-BRE labels can be used as intelligent packaging in food industry.