Interfacial effects of gallate alkyl esters on physical and oxidative stability of high fat fish oil-in-water emulsions stabilized with sodium caseinate and OSA-modified starch.

Effects of sodium caseinate (SC) and its combination with OSA-modified starch (SC-OS; 1:1) alone and with n-alkyl gallates (C0-C18) on the physical and oxidative stability of high-fat fish oil-in-water emulsion were evaluated. SC emulsion contained the smallest droplets and highest viscosity due to the fast adsorption at droplet surfaces. Both emulsions had non-Newtonian and shear-thinning behavior. A lower accumulation of lipid hydroperoxides and volatile compounds was found in SC emulsion due to its better Fe2+ chelating activity. The incorporated short-chain gallates (G1 > G0 âˆ¼ G3) in SC emulsion had a strong synergistic effect against lipid oxidation compared to that of SC-OS emulsion. The better antioxidant efficiency of G1 can be related to its higher partition at the oil-water interface, while G0 and G3 had a higher partition into the aqueous phase. In contrast, G8, G12, and G16 added emulsions indicated higher lipid oxidation due to their internalization inside the oil droplets.

Interfacial behavior of gallic acid and its alkyl esters in stripped soybean oil in combination with monoacylglycerol and phospholipid.

The effect of gallic acid alkyl esters and their combination with monoacylglycerol (MAG) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) on the formation of hydroperoxides and hexanal were determined during the oxidation of stripped soybean oil. Interfacial tension, water content, and droplet size were evaluated to monitor the physical properties of the oil system. Adding MAG and DOPC, especially MAG/DOPC, to the oil promoted the partitioning of antioxidants into the water-oil interfaces by further reducing the interfacial tension. The stripped oil containing methyl gallate (MG) accompanied by MAG/DOPC had lower values of the critical micelle concentration of hydroperoxides and larger micellar size at the induction period. This confirms that MG was able to more effectively reduce the free hydroperoxides concentration and inhibit them in an interfacial way. The conjunction of surfactants has been shown as a promising strategy to improve the interfacial and antioxidant activity of gallates in the oxidative stability of soybean oil.

Improving functionality, bioavailability, nutraceutical and sensory attributes of fortified foods using phenolics-loaded nanocarriers as natural ingredients.

The replacement of artificial by natural additives has gained consumer attention due to concerns about toxic and carcinogenic effects of artificial additives and the growing search for healthy foods. Phenolics are considered as one of the most important natural ingredients in the human diet due to the unique antimicrobial and antioxidant properties. However, the use of phenolics is limited by its poor solubility, undesirable sensorial properties and instability during food processing and storage. To overcome these challenges and to improve the functionality and bioavailability of phenolics, many studies have attempted to encapsulation of phenolics using delivery systems. This review summarizes the recent advances in application of encapsulated phenolics as a natural additive in different food products as well as their effects on functionality and sensory quality. Finally, we have highlighted the key research gaps and future trends in the research domain of application of encapsulated phenolics in foodstuffs. In the literature several studies on physicochemical properties of encapsulated phenolics with different biopolymers and delivery systems were evaluated and based on the results, their applications in various food formulations were suggested for further studies. This review revealed encapsulation techniques especially nanoencapsulation improves the half-stability and functionality of phenolics in fortified food.

Influence of main emulsion components on the physicochemical and functional properties of W/O/W nano-emulsion: Effect of polyphenols, Hi-Cap, basil seed gum, soy and whey protein isolates.

In this study, the effect of natural macromolecules as carrier agents on the biological activity of nano-encapsulated Bene hull polyphenols (Pistacia atlantica subsp. Mutica) through W/O/W emulsions was evaluated. The W/O microemulsions as primary emulsions and a complex of soy protein isolate and basil seed gum (SPI-BSG), whey protein isolate and basil seed gum (WPI-BSG) and also Hi-Cap 100 in the outer aqueous phase were used to produce W/O/W nano-emulsions. Z-average size of emulsions stabilized by Hi-Cap, WPI-BSG, and SPI-BSG was 318, 736.9 and 1918 nm, respectively. The encapsulation efficiency of polyphenols for powders produced by Hi-Cap, WPI-BSG, and SPI-BSG was 95.25, 90.9 and 92.88%, respectively, which was decreased to 72.47, 67.12 and 64.44% after 6 weeks storage at 30 °C. The antioxidant activity of encapsulated polyphenols at 100, 200 and 300 ppm was measured in oil by peroxide and p-anisidine values during storage and was compared to non-encapsulated extract and synthetic antioxidant. Results showed oxidative alterations in oils containing encapsulated polyphenols was lower than unencapsulated form, which among them capsules produced by SPI-BSG exhibited higher antioxidant effects due to the better gradual release. Generally, the higher antioxidant potential was achieved with increased solubility and controlled release of polyphenols through their nano-encapsulation.

Evaluation of antioxidant activity of loquat fruit (Eriobotrya japonica lindl.) skin and the feasibility of their application to improve the oxidative stability of soybean oil.

The effects of ultrasound-assisted, supercritical CO2 and solvent extraction techniques on antioxidant activity of loqua (Eriobotrya japonica Lindl.) skin extract in oxidation stability of soybean oil was evaluated. The antioxidant efficacy of extracts was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH(•)) radical scavenging capacity, ß-carotene/linoleic acid, and Rancimat test system. Results showed that solvent extract of loquat fruit skin at 400 ppm had the highest antioxidant activity compared to ultrasound-assisted and supercritical CO2 extracts. Further, solvent extraction was the most effective method for extraction of phenolic compounds. Protective effects of extracts in stabilization of soybean oil during both frying and storage conditions were tested and compared to tert-butyl hydroquinone (TBHQ) by measuring their peroxide value, free fatty acids, conjugated dienes and trienes value. During frying process solvent extract of skin at 400 ppm (SOEA) exhibited stronger antioxidant activity in oil compared to other oil samples, but this antioxidant potential was lower than TBHQ in storage conditions. Present study showed that loquat fruit skin is a good source of natural antioxidant compounds, and has the potential to be used as a substitute for synthetic antioxidants in vegetable oils.

Influence of extraction techniques on antioxidant properties and bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracts.

In this study, the bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracted by two extraction methods (solvent and ultrasound-assisted) with three solvents (ethanol, water and ethanol-water) were compared to supercritical fluid extraction. The antioxidant activities of skin and pulp extracts were evaluated and compared to tertiary butylhydroquinone (TBHQ) using 2, 2-diphenyl-1-picrylhydrazyl (DPPH˙) radical scavenging, ß-carotene bleaching, and the Rancimat assays. In DPPH assay solvent extracts of skin by ethanol (SSE) and ethanol-water (SSEW) showed strong inhibitory activity. The SSEW also showed the highest inhibition percentage of 85.58% by the ß-carotene bleaching assay and longest induction time of 4.78 h by the Rancimat method. The large amount of tocopherols and phenolics contained in the skin extract may cause its strong antioxidant ability. The results indicated that the solvent extraction with ethanol-water produced the maximum extraction yield of phenolic and tocopherol compounds from loquat fruit skin and pulp. Furthermore, solvent extraction was the most effective in antioxidant activity of the extracts compared to other extraction techniques.

Antioxidative effect of loquat (Eriobotrya japonica Lindl.) fruit skin extract in soybean oil.

The aim of this study was to compare the effects of solvent and ultrasound-assisted extraction methods with supercritical fluid extraction on antioxidant activity of loquat (Eriobotrya japonica Lindl.) fruit skin extract in stability of soybean oil at 25°C. Oxidative stability alterations of soybean oils containing 400 (SEA) and 1000 ppm (SEB) of ethanol extract, 400 (SSA) and 1000 ppm (SSB) of supercritical CO2 extract, 400 (SUA) and 1000 ppm (SUB) of ultrasound-assisted extract, and 100 ppm of tertiary butylhydroquinone (TBHQ) were monitored by measuring the peroxide value, thiobarbituric acid value, free fatty acids, conjugated dienes and trienes values. Oxidative changes in SEA were lower than that of oils treated with other extracts, but the best protection was observed in soybean oil consisting TBHQ. The solvent extraction method produces the maximum amount of phenolic and tocopherol compounds from loquat fruit skin. Therefore, solvent extraction method had a better effect on antioxidant activity of the loquat fruit skin extract.

Frying stability of sunflower oil blended with jujube (Ziziphus mauritiana Lam.) leaf extract.

The aim of present study was to compare the effects of ultrasound-assisted and microwave-assisted extraction with solvent extraction method on antioxidant activities of jujube (Ziziphus mauritiana Lam.) leaf extracts in stability of sunflower oil during deep frying. The antioxidant activities of the extracts were evaluated by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH˙) radical scavenging and ß-carotene bleaching assays. Ultrasound-assisted extraction was the most effective method on antioxidant activities of extracts and extraction yield of phenolic compounds compared to other extraction techniques. Protective effect of methanol-water extract of jujube leaf obtained with ultrasound-assisted extraction (ULMW) at 500 and 700 ppm in stability of sunflower oil was compared to synthetic antioxidants by measuring total polar compounds (TPC), carbonyl value (CV), peroxide value (PV), free fatty acids (FFA), oxidative stability index (OSI), conjugated dienes (CD), and trienes values (CT). Results showed ULMW at 700 ppm had higher stabilization efficiency than synthetic antioxidants.