Phenolic Extracts from Vaccinium corymbosum L. Loaded in Microemulsions and Liposomes as Enhancers of Olive Oil Oxidative Stability

Abstract

Natural phenolic compounds are recognized as bioactive ingredients in food but can also have a role as effective alternatives to synthetic antioxidants in stability improvement of foods prone to oxidation, such as edible oils. This study aimed at the preparation and HPLC-DAD characterization of phenolic extracts from Vaccinium corymbosum L. (raw, pasteurized, freeze-dried and treated with high-intensity ultrasound), and at testing their antioxidant potential in the prevention of olive oil oxidation in the native state and encapsulated into microemulsions and liposomes systems. Water-in-oil structured microemulsions used in this study were prepared using mechanical, ultrasonic, and high pressure homogenization. Liposomes with the average size of 589.1±2.9 nm were produced with the proliposome method using commercially available phosphatidylcholine-Phospolipon 90G. The obtained results showed signifi cant prolongation of the oxidative stability of extra virgin olive oil enriched with encapsulated blueberry phenolic extracts than with native phenolic extracts, regardless of the method used for blueberry processing. Phenolic extracts encapsulated in microemulsions had a stronger effect on the prolongation of olive oil oxidative stability in comparison with the extracts encapsulated in liposomes. The average prolongation rate of oxidative stability was 45.65% by phenolic extracts encapsulated in microemulsions prepared by mechanical homogenization (p=0.012), and 58.72% by microemulsions prepared by ultrasound homogenization (p=0.011). Phenolic extracts encapsulated in microemulsions prepared by high pressure homogenization had no effect on oil oxidative stability prolongation.

Sunflower (Helianthus annuus L.) Plants at Various Growth Stages Subjected to Extraction—Comparison of the Antioxidant Activity and Phenolic Profile

“…The consumption of antioxidants in food and dietary supplements has been linked to a reduced risk of these diseases [4,5]. Antioxidants also play an important role in extending the shelf life of food [6][7][8]. Utilized as additives, they limit the oxidation of food product ingredients, especially lipids.…”

The effect of freeze‐drying, pasteurisation and high‐intensity ultrasound on gastrointestinal stability and antioxidant activity of blueberry phenolics

“…The experiment was designed using the Multi‐Factor Categorical Design provided by the STATGRAPHICS Centurion (Stat Point Technologies, Inc., Warrenton, VA, USA) Software, as described by Liović et al . (2019). Table 1 (already published in Liović et al .…”

Terpenoids and Polyphenols as Natural Antioxidant Agents in Food Preservation

“…There is an increasing interest in exploring the use of encapsulation techniques for protecting and increasing the bioactive properties of natural antioxidant compounds added to edible oils. The use of microemulsions has been shown to greatly enhance the effect of anthocyanin rich blueberry ( Vaccinium corymbosum L.) phenolic extracts on the prolongation of the oxidative stability of extra virgin olive oil when compared with the effect of native blueberry phenolic extracts [ 133 ]. Olive leaves are one of the richest sources of phenolic compounds among the different parts of the olive tree, oleuropein and its derivatives, such as hydroxytyrosol and tyrosol ( Figure 5 ), being the most abundant.…”