Biodegradable packaging based on chitosan-potato starch biopolymer containing Apium graveolens seed extract for chicken fillets

The consumer demand to use natural preservatives in food products instead of synthetic ones and awareness about not using plastic is increasing. In this research, chitosan-potato starch film containing celery seed extract was prepared at different concentration levels (0.5, 2 and 8%) and the physical properties of the film (thickness, moisture content and solubility), mechanical properties and antioxidant activity also determined. Then, the chicken fillet wrapped by the film was kept in the refrigerator for 15 days and the microbial growth and primary and secondary oxidation compounds formation with peroxide value and thiobarbituric acid and sensory evaluation was also monitored during the storage time. The results showed that the total phenol and flavonoid content of celery seed extract was 70.67±7.8 mgGA/g of extract and 62.81±5.65 mg Quercetin/g of extract, respectively. Addition of celery seed extract (2 and 8%) decreased the moisture content and solubility of the film due to the increase of the film hydrophobicity. Also, by adding the celey seed extract, the elongation at break of the film increased, while the tensile strength and elastic modulus decreased. With the increase in the concentration of the celery seed extract in the film, the DPPH free radical inhibition increases from 14.69 to 73.94%. According to the results of microbial and oxidation tests as well as sensory evaluation, coating a chicken fillet with a chitosan-potato starch film containing 8% celery seed extract would increase its shelf life by up to 15 days.