Introduction of the Peel of Iranian Pomegranate as a Potential Natural Additive in Food by Phytochemical-based Characterization of Different Genotypes

Over the past decades, the use of natural additives has increased as an alternative to artificial ingredients in the food industry. The purpose of this study was to investigate the potential of pomegranate peel (PP) as a natural food additive. Many factors, including genotype, could affect the quality of PP as a by-product of juice production with many nutritional, functional and anti-infective properties. In this study, the most significant phytochemical characters of thirty Iranian pomegranate peels (IPP) from different genotypes, including total phenolic (TPC) and flavonoid content (TFC), and nine phenolic compounds were determined. The HPLC-DAD-MS results of PPEs revealed nine phenolic compounds in the IPP extracts. Punicalagin β, punicalagin α, and ellagic acid were the main components constituting 20.8–48.7, 13.9–30.1, and 1.6–13.4 μg/mg DW, respectively. The peel of IPP23 (Kabdar-Shirin-e- Behshahr) contained the highest quantity of polyphenolic compounds. Also, TPC and TFC of the peel extracts ranged between 66.38 and 181.41 mg GAE/ g DW and 38.5 to 144.13 mg RE/ g DW, respectively. Eventually, antioxidant potential estimated by the DPPH assay ranged between 4.1 and 14.4 μg/ml. The results showed that the antioxidant property of pomegranate peel extracts is significantly higher than the standard of gallic acid. Also, the peel of the genotypes that had high phenolic compounds were introduced as superior genotypes. The results of HCA showed that, among the studied genotypes, the peel of IPP23 can be introduced as a potential source of natural preservatives in the food industry.