Shelf-life extension using bioplastic films incorporated with black seed oil

Spoilage is estimated at $165.6 billion dollars yearly in the United States with meats accounting for 41%. The CDC reported in 2013, over 19,000 cases of food borne infection, 4,200 leading to hospitalization, and 80 deaths. Black seed (Nigella sativa) has shown antimicrobial properties, but due to flavor, it should be incorporated into packaging. This research looked at the impact of black seed oil (BSO) incorporated into bioplastics on bacterial growth. Corn, rice, and potato starches were used to make bioplastic trays (BT) using 90 g starch, 180 mL water, 6 mL glacial acetic acid, 9 mL glycerol, and 300 ppm BSO in test samples. Rapid Visco Analysis (RVA) was performed on starches to identify thermal breakdown. The bioplastics were esterified under agitation at 62°C before drying. Beef, chicken, and shrimp were inoculated with Escherichia coli K12, Staphylococcus epidermidis, or Pseudomonas putida broths, respectively. Each protein was placed onto a BT, covered, and refrigerated at 5°C for 5 days before measuring the total bacterial load through ATP illuminometer. When comparing RVA, the potato starch showed the quickest peak time but the highest thermal breakdown. The corn starch had the slowest peak time and the least thermal breakdown. The BSO varied in efficiency depending on the microorganism and BT substrate. A greater reduction was seen in E. coli on rice BT and Staphylococcus on potato BT. This research was aimed at reducing food spoilage and landfill waste. The anticipated higher material costs can be justified by the increased safety and extended shelf life of the foods protected.