RESUMEN
Borage seed oil (BSO), peppermint oil (PO) and lycopene (LC) have accomplished a lot of interest due to their therapeutic benefits in the food and pharmaceutical sectors. However, their employment in functional food products and dietary supplements is still precluded by their high susceptibility to oxidation. Thus, the encapsulation can be applied as a promising strategy to overcome these limits. In the present study, doubly layered water/oil/water (W/O/W) nanoemulsions were equipped using purity gum ultra (PGU), soy protein isolate (SPI), pectin (PC), whey protein isolate (WPI) and WPI-PC and SPI-PC complexes, and their physico-chemical properties were investigated. Our aim was to investigate the influence of natural biopolymers as stabilizers on the physicochemical properties of nanoemulsified BSO, PO and lycopene thru W/O/W emulsions. The droplet size of the fabricated emulsions coated with PGU, WPI, SPI, PC, WPI-PC, and SPI-PC was 156.2, 265.9, 254.7, 168.5, 559.5 and 656.1 nm, correspondingly. The encapsulation efficiency of the entrapped bioactives for powders embedded by PGU, WPI, SPI, PC, WPI-PC, and SPI-PC was 95.21%, 94.67%, 97.24%, 92.19%, 90.07% and 92.34%, respectively. In addition, peroxide and p-anisidine values were used to measure the antioxidant potential of the entrapped bioactive compounds during storage, which was compared to synthetic antioxidant and bare natural antioxidant. The collected findings revealed that oxidation occurred in oils encompassing entrapped bioactive compounds, but at a lower extent than for non-encapsulated bioactives. In summary, the findings obtained from current research prove that the nanoencapsulation of BSO surrounded by innermost aqueous stage of W/O/W improved its stability as well as allowed a controlled release of the entrapped bioactives. Thus, the obtained BSO-PO-based systems could be successfully used for further fortification of food-stuffs.
RESUMEN
Borage seed oil (BSO) is one of the richest sources of γ-linolenic acid and linoleic acid, which are considered to retain plenty of health promoting benefits. However, its application in functional foods and dietary supplements remains limited owing to its superior vulnerability to oxidation. To solve this problem, ultrasound-assisted BSO-loaded nanoemulsions were prepared with modified starch incorporating different concentrations of peppermint oil (PO), as a natural antioxidant. The influence of different PO levels on the mean droplet size, rheology attributes, and oxidative stability of nanoemulsions stored at various temperatures (4, 25, and 40 °C) during 30 days storage was analyzed. In addition, DPPH and ABTS assays were used to determine the antioxidant activity and antioxidant capacity of BSO-loaded nanoemulsions, respectively. The optimized formulation (NE3; 5:5% v/v PO: BSO) exhibited a slight change in droplet size and oxidative stability at all temperatures during storage compared to other formulations. At a concentration of 328.08 µL/mL, formulation NE3 presented the minimum DPPH IC50 at 40 °C, which was lower than other formulations. The findings of this study revealed that the maximum retained antioxidant capacity (99.42 µg Trolox/mL) was related to NE3 comprising (5:5% v/v PO: BSO) stored at 40 °C for 30 days; which could be accredited to the role of PO as a natural antioxidant in order to improve the oxidative stability of nanoemulsion delivery system. Taken together, co-encapsulation of BSO and PO within nanoemulsions provides novel insights regarding the development of functional foods, dietary supplements and beverages.