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Pomegranate (Punica granatum) bioactive compounds (polyphenols and anthocyanins) of juice (PJ) and ethanolic extracts (PE) were encapsulated with maltodextrin (MD) or soybean protein isolates (SPI) by spray drying using a 2 2 statistical factorial design for each systems studied (PJ-MD, PJ-SPI, PE-MD and PE-SPI) considering the proportion of coating material and the inlet temperature as independent variables. The stability of the bioactive compounds microcapsules powders obtained under optimal conditions for each system was studied at 60°C in oven for 56 days. The polyphenols encapsulating efficiency was significantly better in SPI matrix whereas for anthocyanins was in MD matrix. By the other hand, during the storage, the MD microcapsules provided a significant greater protective effect on the polyphenols and anthocyanins than SPI, as was shown by the lower degradation rate constants. When the microcapsules were added to yogurt the stability of the bioactive compounds followed a similar behaviour to those without encapsulation, except for PE-MD.

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The effect of the addition of olive leaf (Olea europaea, cv. Arbequina) extracts, i.e. hydroalcoholic (ethanol-water 1:1; OHE), juice (OJ) and supercritical fluid-CO 2 (OSFE) on the oxidative stability of vegetable oils with different unsaturation, such as soybean oil (SBO), canola oil (CO) and high oleic sunflower oil (HOSO), were studied at two concentrations (250 and 630 mg/kg oil, expressed as caffeic acid equivalent (CAE)). The extracts were characterized by the total phenolic content (Folin-Ciocalteau method), phenol chromatographic profiles (LC-MS) and antioxidant activity (DPPH). OHE showed the highest phenol content (7.7 mg CAE/mL) while OJ and OSFE showed values of 5.4 and 2.2 mg CAE/mL, respectively. Oleuropein and its derivatives were the major phenolic compounds identified in OHE. The addition of 630 mg CAE/kg oil of OHE and OSFE to HOSO, SBO and CO showed an antioxidant effect, increasing significantly the induction time (IT) ( p<0.05). That effect was highest when the system was more monounsaturated. In contrast, OJ showed a pro-oxidant effect for all oils systems for both concentration studied. This behaviour could be attributed to the diphenol oxidase (PPO) activity.

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