Annals of the University Dunarea de Jos of Galati. Fascicle VI: Food Technology (Dec 2012)
Enriched antioxidant activity of pear juice by supplementation with oregano and wild thyme extracts
Abstract
In the last years, it has been noticed an increased interest in natural antioxidants and the use of these compounds in the field of new polyphenol-rich drinks. Antioxidants are compounds responsible for free radical scavenging in the body. They protect the organism from oxidative modification of cells and tissues. The aim of this study was to improve the antioxidant capacity of a pear juice, as well as its compounds stability during 12 days of storage. The stabilization of phenols and their delivery in pear juice was possible thanks to microemulsions obtained by mixing different ratios of oil, surfactant and cosurfactant. The characterization ofmicroemulsions was performed using pseudoternary phase diagrams and which have highlighted reports of mixing A / W / S / CoS corresponding states of microemulsion. The obtained microemulsions have stability and provides good stabilization of linoleic acid and walnuit oil, up to 70% w/w water. Through conductometric analysis we have highlighted the transition states of micro W/O, O/W bicontinuous structures. The pear juice with plant extracts had higher antioxidant values than the pear juice with synthetic antioxidants. Thus the juice with oregano improved the antioxidant capacity approximately 1.45 times compared to the juice with BHA and approximately 1.67 times compared to the juice with BHT. These results are promising in order to replace the synthetic antioxidants with natural antioxidants.
