Effects of tocopherol, rosemary essential oil and Ferulago angulata extract on oxidative stability of mayonnaise during its shelf life: A comparative study.

The purpose of this study was to investigate the effects of tocopherol, rosemary essential oil and ferulago on oxidative stability of mayonnaise during storage. Their efficacy was also compared with tertiary butylhydroquinone (TBHQ) and the control group. During the primary oxidation stage, tocopherol was more efficient than TBHQ, while in the secondary oxidation stage it was the same as other antioxidants. At end of storage, samples with added rosemary essential oil and ferulago extract showed peroxide value (2.29 and 2.80 meq O2/kg oil), anisidine value (11.83 and 12.23), hexanal and heptanal concentration (510.2, 589.9 and 76.6, 75.2 ng/g), respectively, which were meaningfully less than those of the control sample (10.44 meq O2/kg, 18.32, 1339.8 ng/g, and 225.5 ng/g, respectively). Based on the overall results, tocopherol and rosemary essential oil can be recommended as replacement for TBHQ. However, further evaluation needs to be performed on the organoleptic properties of Ferulago extract.

Microencapsulation of microbial canthaxanthin with alginate and high methoxyl pectin and evaluation the release properties in neutral and acidic condition.

Canthaxanthin (CX) is an orange-red keto-carotenoid with high antioxidant activity. This functional pigment is sensitive to oxygen, light, pH and heat. In this study, CX was produced by the Dietzia natronolimnaea HS-1 and was encapsulated in Alginate (Alg) and Alg-high methoxyl pectin (HMP) through O/W/O multiple emulsion/external gelation method to developed resistant microparticles among acidic and neutral pHs. Results showed that initial CX concentration had a significant influence on total CX (TCX), surface CX (SCX), microencapsulation efficiency (EE) and particles size. The highest EE% for Alg (60.21 ±â€¯0.18) and Alg-HMP (70.60 ±â€¯0.68) were obtained with CX initial concentration of 11 and 18 µg/mg, respectively. Alg microparticles showed smaller size compare to Alg-HMP microcapsules. Presence of CX in microparticles and good antioxidant activity was confirmed by FT-IR spectroscopy and DPPH assay, respectively. CX in vitro release was 66% and 49% in acidic condition and 76% and 50% in neutral condition for Alg and Alg-HMP, respectively. Thus, Alg-HMP-CX18 microparticles were selected to be used in both neutral and acidic foods such as milk and fermented milks products as an antioxidant and a colorant agent.

Effect of extraction process on composition, oxidative stability and rheological properties of purslane seed oil.

Purslane seed oil could be considered as potential nutritious oil due to its desirable fatty acid composition and other biological active compounds. In this study the effect of three extraction procedure including solvent extraction, cold pressing and microwave pretreatment (MW) followed by cold pressing on oil yield, physicochemical properties, oxidative stability and rheological behaviors of oil was investigated. Solvent extracted oil had the highest extraction yield (72.31%). Pretreatment by microwave before cold press extraction resulted in an increase in extraction yield, total phenolic compound (TPC) and antioxidant activity. Cold press extracted oil had the lowest oxidative stability (4.64h). This property was greatly enhanced by microwave irradiation, so that the longest oxidative stability was found in MW-cold press extracted oil with 9.67h. Furthermore, all extracted oils demonstrated Newtonian flow behaviors. MW-cold press extracted oil had the greatest apparent viscosity and highest sensitivity to temperature changes (Ea=29.18kJ/mol-1).