Impact of zataria multiflora essential oil, nisin, potassium sorbate and LDPE packaging containing Nano-ZnO on shelf life of caviar

Abstract

Caviar is one of the most luxury foods in the world. In addition to the traditional method (using salt and preservative with low temperature), there are various methods to extend the shelf life of caviar. The main objectives of this study were to evaluate the capabilities of Zataria multiflora essential oil (0.03%, 0.06%(W/W)), nisin (9, 18 mg/kg), potassium sorbate (500 and 1000 mg/kg) and LDPE package containing 0.4 and 1%(W/W) nano-ZnO on the shelf life, as a new approach in caviar. Total aerobic bacteria, molds & yeasts and color of samples were evaluated immediately after packaging and after 30, 60, 90, 120 and 150 days of storage. Results showed that LDPE package containing 1%(W/W) nano-ZnO have the most capability to control total aerobic bacteria. While for molds and yeasts count, 0.06%(W/W) Zataria multiflora essential oil had the most significant effect on the caviar samples (p < 0.05). For color changes analysis, there were significant differences between all of the treatments except 500 mg/kg potassium sorbate and 18 mg/kg nisin. Minimal color changes were observed in caviar samples packaged in LDPE film containing nano-ZnO. The results also showed a considerable Zn migration from package to caviar that its rate increased after 40 days.