Process development and life cycle assessment of pomegranate biorefinery

According to the global survey, Iran, China, India, and USA are leading producers of pomegranate. Among them, India tops the chart as the highest producer of pomegranate, cultivating 1.14 million tons per annum. Peels cover 50% weight of whole pomegranate fruit and are mostly discarded as waste. This enormous peel waste has innumerable health benefits. Pomegranate peel (PP) constitutes various antioxidants, anthocyanins, and polyphenols such as ellagic acid, pectin, gallic acid, and many others which can be extracted. A detailed process for sequential extraction, with zero discharge, of such valuable chemicals from biorefinery point of view is developed in this study. Major products considered for extraction include ellagic acid (EA), lignin, and pectin. Also, the total phenolic content (TPC) and total reducing sugar (TRS) content are found in the intermediate stages. The percent yield of the products EA, lignin, and pectin is 10%, 13%, and 19% with respect to the weight of pomegranate peels (PP) processed. For the first time, a sequential extraction of products with its detailed process flow diagram, process inventory, and life cycle assessment (LCA) of PP biorefinery is presented. The global warming potential of the PP biorefinery is found to be 4505.8 kg CO₂ eq. per ton of PP processed. The intense hydrolysis step contributed majorly to the overall GWP indicator.