Physico-chemical properties and fatty acid profile of seed oils from pomegranate (Punica granatum L.) extracted by cold pressing

摘要

Pomegranate (Punica granatum L.) seeds are normally waste products from pomegranate fruit processing but they are a valuable source of certain pharmaceutical and nutraceutical compounds. This study was performed to determine and compare the physico-chemical properties of oils of pomegranate seed extracted by cold pressing from the variety Torshe Malas Iran (TMOI) and two commercial oils from Iran (COI) and Turkey (COT). Fatty acid analysis indicated that all the oil samples had a dominant fatty acid, punicic acid, with the other prominent fatty acids being linoleic and oleic acids. The thermal behavior of the three oils was determined using differential scanning calorimetry, which gave melting points of TMOI (-12.70°C), COI (1.87°C), and COT (2.25°C). TMOI was found to have the most favorable chemical quality attributes, including a low peroxide value (4.67meq/kg), low free fatty acid content (0.65% as punicic acid), and high total phenolic content (10.44 mg GAE/g sample), followed by COT. Analysis of flavor compounds was conducted using fast gas chromatography-surface acoustic wave technology, which allowed detection of 13 distinct aromas among the three oils. Overall, the physico-chemical properties of the three oils were superior to those of pomegranate seed oils extracted using organic solvents reported previously.