Cryogenic grinding of pomegranate peel

Cryogenic grinding of pomegranate peel at the optimized condition of ball diameter (3 mm), drum oscillation (3000 rpm), and grinding time (20 min) temperatures was performed and was compared with pomegranate peel powder produced through the ambient grinding technique. Comparative analyses of peel powder were carried out to determine the various quality attributes by employing physical and phytochemical analyses. The loss of minerals after ambient grinding was nearly more than 50% as compared to cryogenic grinding. In the cryogenically ground peel powder, the quality and nutritional attributes studied were considerably preserved with the total polyphenol, total hydrolysable tannins, total flavonoid, and antioxidant values being 204.71 mg gallic acid equivalent (GAE)/g of dry weight (DW), 94.54 mg tannic acid equivalents (TAE) /g of DW, 50.21 mg quercetin equivalents (QE) /g of DW and 65.43% respectively. The cryogenically grinding method was dominant to ambient grinding with regards to phytochemical compound retention in the final pomegranate peel powder. The powder particle size attained for the pomegranate peel ground under cryogenic and ambient conditions were 83 μm and 169 μm, respectively. This work will high spot the association between cryogenic grinding and the preservation of phytochemical compounds in pomegranate peel powder. The physical, phytochemical analyses, mineral analyses, Scanning electron microscopy (SEM) analyses, and Fourier Transform Infrared Spectroscopy (FTIR) analysis data attained for cryogenic ground pomegranate peel powder proposes their enormous prospective to be applied in food fortification. Furthermore, it diminishes harm associated with the disposal of peel waste and progresses the quality and functionality of the food. The outcomes of this work will edify the scientific community on the application of liquid nitrogen during the grinding operation of thermo-sensitive compounds.