Roselis Carmona-García

Effect of oil extraction assisted by ultrasound on the physicochemical properties and fatty acid profile of pumpkin seed oil (Cucurbita pepo).

The effects of amplitude and time of ultrasound-assisted extraction on the physicochemical properties and the fatty acid profile of pumpkin seed oil (Cucurbita pepo) were evaluated. Ultrasound time (5-30 min) and the response variables amplitude (25-100%), extraction yield, efficiency, oxidative stability in terms of the free fatty acids (FFA) of the plant design comprising two independent experiments variables, peroxide (PV), p-anisidine (AV), totox value (TV) and the fatty acid profile were evaluated. The results were analyzed by multiple linear regression. The time and amplitude showed significant differences (P<0.05) for all variables. The highest yield of extraction was achieved at 5 min and amplitude of 62.5% (62%). However, the optimal ultrasound-assisted extraction conditions were as follows: ultrasound time of 26.34 min and amplitude of 89.02%. All extracts showed low FFA (2.75-4.93% oleic acid), PV (1.67-4.68 meq/kg), AV (1.94-3.69) and TV (6.25-12.55) values. The main fatty acids in all the extracts were oleic and linoleic acid. Therefore, ultrasound-assisted oil extraction had increased performance and reduced extraction time without affecting the oil quality.

Evaluation of physical and chemical properties of carrots dried by Refractance Window drying

ABSTRACT The Refractance Window™ (RW) technique was used to dry carrot slices (3 cm diameter; 0.2 and 0.4 cm thickness) at 74 and 94°C. Moisture loss, texture, color, total polyphenol content (TPC), and antioxidant activity (AA) were evaluated as response variables and were compared with the values of a control (fresh carrot) and the slices dried via convective drying (C) at the same temperatures. The RW method produced a reduction of drying time of 26–51% (p < 0.05) when compared to convective drying. The color, TPC, and AA values for the RW treatment did not differ (p > 0.05) compared with the control. The texture values showed a difference with respect to the control for the two drying methods used. However, between the two drying methods there was no difference in the texture (p > 0.05). The results suggest that the RW technology can be used to develop products with better functional properties compared with those obtained via conventional air-drying methods.

Impact of micronized starfruit (Averrhoa carambola L.) fiber concentrate on lipid metabolism in mice

Abstract The objective of this study was to evaluate the effect of micronized insoluble fiber from starfruit bagasse as an ingredient of a functional food (FF) or as micronized insoluble fiber-rich fraction (IFRF) and its effects in vivo on lipids metabolism in a murine model. Experimental animals were divided in four isoproteic (15.8%) treatments differing on the fiber and cholesterol level used. The micronized IFRF particle size ranged from 37.5 to 149 μm. Treatments with added IFRF and those including the FF lowered serum triacylglycerols, total cholesterol (TC), high-density lipoproteins (HDL), and low-density lipoproteins (LDL) concentrations (IFRF: 14.2, 25.4, 55.06, and 12.18%, respectively; FF: 30.18, 39.47, 35.11, and 43.18%, respectively). IFRF produced the overall highest serum hypolipidemic effect and prevented the development of non-alcoholic fatty liver. Both the IFRF and the FF exhibited hypolipidemic effects that suggest a potential role of starfruit insoluble fiber as a component of FFs aimed against cardiovascular diseases.

Effect of osmotic dehydration on the physical and chemical properties of Mexican ginger (Zingiber officinale var. Grand Cayman)

The aim of this study was to evaluate the effect of osmotic dehydration of ginger on the properties of color, total polyphenol content (TPC) and antioxidant capacity (AC). Fresh samples were pretreated with scalding (100°C/1.0 minute). Water loss (WL) and solid gain (SG) kinetics were performed using three sucrose concentrations: 35%, 50% and 65% at three temperatures: 40°C, 55°C and 70°C. WL and SG simulated kinetics by Diffusion model for cubes averaged a R2 of 0.95. The diffusivities for water and solid by Fick’s Law obtained maximum values of 6.81 × 10−7 and 2.65 × 10−7 m2/s, respectively. WL results were obtained up to 60.83% and SG 32.24%. Ginger treatments without blanching (GWB) at 40°C with 35% and 50% sucrose, respectively, showed a similar fresh ginger color. The GWB treatments showed the higher TPC using 50% sucrose at 40°C (753 μg GAE/mL) and AC (341.96 mg AAE/mL).