Active biodegradable thermoformed trays from PLA/EDTA with ethyl lauroyl arginate: Thermoformability, migration, and microbial control in processed meats

This study evaluates polylactic acid (PLA) incorporating ethyl lauroyl arginate (LAE at 0–30 g/kg) with ethylenediaminetetraacetic acid (EDTA, 50 g/kg) to improve thermoformability, heat-seal behavior, and food preservation. Fourier transform infrared spectroscopy showed limited spectral changes after EDTA and LAE incorporation because of overlap with the dominant PLA bands. Combined with scanning electron microscopy observations, the results suggested reduced visible EDTA aggregation after LAE addition. LAE reduced crystallinity (7.7% in PLA to 2.4% in PLA/EDTA/30 LAE) and crystallization temperature. Mechanical testing showed LAE decreased strength and stiffness with increased elongation at break, indicating enhanced ductility. Seal strength decreased with LAE addition at all dwell times, although longer dwell time partly increased seal strength. At high LAE content, the sheets showed a more peelable seal behavior. LAE lowered the thermoforming temperature from 130 to 95 °C and improved stretchability and thickness uniformity. Overall migration was excessive in acidic and fatty simulants; trays suit low-fat refrigerated products. PLA/EDTA/30 LAE showed strong in-vitro activity against Staphylococcus aureus and maintained microbial counts <6 log CFU/g through day 6 in ham and day 4 in smoked chicken sheets, compared with spoilage of controls within 2-3 days.