Solar drying, hygroscopic equilibrium and biochemical quality of Punica granatum legrelliae’s flowers

Punica granatum Legrelliae is a valuable medicinal plant that is widely planted in Morocco. The equilibrium moisture content was investigated. Peleg model was found the most suitable to describe the sorption phenomenon. The drying kinetic of Punica granatum Legrelliae’s flowers was investigated by using a convection solar dryer. Midilli-Kucuk model described well the drying curves’ trend. The effective moisture diffusivity values were obtained. The Arrhenius relation, with an activation energy value of 92.91 kJ.mol-1 expressed the temperature effect on the diffusion coefficient. Finally, the effect of drying these flowers at different temperatures on their quality was investigated. To assess the quality of the product after solar drying; the color, polyphenols content, antioxidant activity, and polyphenoloxydase and peroxydase activities were considered. 40 °C was the best drying temperature for the preservation of color and bioactive molecules with antioxidant property

Chemical Composition of Pistacia lentiscus Seeds’ Oil from Moroccan High Atlas Mountain

Pistacia lentiscus is an aromatic member of the Anacardiaceae family, endemic to the Mediterranean regions, which produces red and black oleaginous seeds in maturity. Our study focuses on the characterization of Pistacia lentiscus seed oils from three localities of High Atlas Mountain in the Azilal region of Morocco. Our results showed a very appreciable oil yield reaching more than 21% which clearly differs between the three sites studied (21.33 ± 0.17% in Boizoghrane, 15.22 ± 0.10% in Tighanimine, and 7.67 ± 0.29% in Tawjanizm locality); the analysis of the total fatty acids composition revealed a predominance of the unsaturated fatty acids represented essentially by the oleic and linoleic fatty acids, and also the triglyceride composition was dominated mainly by POO + SOL, POL + SLL + PoOP, and OOO. This potential of the chemical composition offers the possibility of producing nutraceutical oil, which represents a source of income capable of insisting vulnerable local populations to protect this species from deforestation, thus maintaining biodiversity, and to reduce by this interest the migratory flow from marginal areas

Antioxidant and anti-browning activities of Mentha suaveolens extracts

The inhibition of enzymatic browning and oxidation is still an important challenge in food processing. This study was designed to examine in vitro the inhibition of enzymatic browning in apple and the antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferrous ion chelating activity by Mentha suaveolens phenol, methanol and aqueous extracts. The use of various extracts in the prevention of the enzymatic browning, catalysed by polyphenol oxidases (PPO) and peroxidases (POD) showed that the phenol extract had a high effect on PPO more than synthetic inhibitor (potassium sorbate), whereas all extracts of M. suaveolens presented only a minor effect on POD of apple. The radical scavenging activity of various extracts of M. suaveolens using DPPH showed that the phenol extract had same activity as butyl hydroxyl toluene (BHT) which is a known inhibitor for its antioxidant activity. The highest ferrous ion chelating activity was found in phenol and methanol extracts. The chemical analysis of the phenol extract using the high performance liquid chromatography (HPLC) suggests that the rosmarinic acid could explain the observed inhibition. In conclusion, these data suggest that the M. suaveolens compounds can act as preservatives of food against oxidation and enzymatic browning.Keywords: Mentha suaveolens, phenolic compounds, enzymatic browning, antioxidant activit

Effect of Adding Thymus leptobotrys on Extra Virgin Olive Oil’s Quality and Physicochemical Parameters

The present study aimed to evaluate the changes in extra virgin olive oil (EVOO) after enrichment treatments with Thymus leptobotrys, a Moroccan endemic aromatic plant. The EVOO sample was supplemented with two materials obtained from the aerial parts of T. leptobotrys: powder (2.5 and 5%) or essential oil (100 and 200 ppm). The chemical composition analysis of T. leptobotrys extracts (essential oil and powder methanolic extract) allowed the determination of its phenolic profile. Quality parameters (acidity, peroxide value, and specific extinction coefficients), color, fatty acids composition, minor components (pigments and phenol), and Rancimat oxidative stability of the control and enriched oils were measured. Rosmarinic acid and thymusin were the main identified compounds in the powder; thymusin was identified for the first time in the essential oil where it was predominant. Generally, the enrichments did not downgrade the oil from its initial category (EVOO), according to quality indexes. Adding T. leptobotrys to EVOO, especially the essential oil, enriched its phenolic profile by allowing the migration of thymusin, a lipophile flavone, without affecting its quality parameters or color

Emulsion Formation and Stabilizing Properties of Olive Oil Cake Crude Extracts

The surface-active and emulsifying properties of crude aqueous ethanolic extracts from untreated olive oil cake (OOC) were investigated. OOC extracts contained important concentrations of surface-active components including proteins, saponins and polyphenols (1.2–2.8%, 7.8–9.5% and 0.7–4.5% (w/w), respectively) and reduced the interfacial tension by up to 46% (14.0 ± 0.2 mN m−1) at the oil–water interface. The emulsifying ability of OOC extracts was not correlated, however, with their interfacial activity or surface-active composition. Eighty percent aqueous ethanol extract produced the most stable oil-in-water (O/W) emulsions by high-pressure homogenization. The emulsions had average volume mean droplet diameters of approximately 0.4 µm and negative ζ-potentials of about −45 mV, and were stable for up to 1 month of storage at 5, 25 and 50 °C. They were sensitive, however, to acidic pH conditions (<5) and NaCl addition (≥25 mM), indicating that the main stabilization mechanism is electrostatic due to the presence of surface-active compounds with ionizable groups, such as saponins

Effects of Virgin Olive Oil Phenolic Compounds on LDL Oxidation and Vasorelaxation Activity

This study examined the efficacy of virgin olive oil phenolic extract and other phenolic compounds (oleuropein, caffeic acid) in preventing oxidative modifications of human low density lipoprotein oxidised by CuCl2. The vasorelaxant effect of these compounds on rat aortic ring with and without functional endothelium is also discussed. Olive oil phenolic extract, caffeic acid and oleuropein increased the lag time of conjugated diene formation in a concentration-dependent manner. Moreover, phenolic extract produced a vasorelaxant effect that persisted in denuded aorta and after inhibition of nitric oxide synthase by N$^{\rm{G}}$-methyl-L-arginine (L-NMMA) or methylene blue. Oleuropein did not produce a relaxant effect, whereas caffeic acid produced partial relaxation at concentration 0.5 g/L