Effects of the extraction conditions on the yield and composition of rice bran oil extracted with ethanol-A response surface approach

Rice bran oil was obtained from rice bran by solvent extraction using ethanol. The influence of process variables, solvent hydration (0-24% of water, on mass basis), temperature (60-90 degrees C), solvent-to-rice bran mass ratio (2.5:1 to 4.5:1) and stirrer speed (100-250 rpm) were analysed using the response surface methodology. The extraction yield was highly affected by the solvent water content, and it varied from 8.56 to 20.05 g of oil/100 g of fresh rice bran (or 42.7-99.9% of the total oil available) depending on the experimental conditions. It was observed that oryzanol and tocols behave in different ways during the extraction process. A larger amount of tocols is extracted from the solid matrix in relation to gamma-oryzanol. It was possible to obtain values from 123 to 271 mg of tocols/kg of fresh rice bran and 1527 to 4164 mg of oryzanol/kg of fresh rice bran, indicating that it is feasible to obtain enriched oil when this renewable solvent is used. No differences in the chemical composition of the extracted oils were observed when compared to the data cited in the literature. (C) 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Spray drying microencapsulation of Lippia sidoides extracts in carbohydrate blends

The microencapsulation of Lippia sidoides extracts in blends of carbohydrates was investigated. The extraction conditions were determined through a 2(2) factorial design. The effects of the plant:solvent ratio (A - 7.5:100 and 15:100 m/m) and the extraction time (B - 30 and 90 min) on thymol content of extractive solutions were evaluated, using a 2:1 (v/v) of ethanol:water at a temperature of 50 degrees C, as a solvent system. The selected extract was subjected to spray drying. Blends of maltodextrin and gum arabic at different proportions (4:1; 3:2; 2:3; 0:1) (m/m) were used as encapsulating material. The protective effects of the maltodextrin and gum arabic blends were evaluated by determination of the thymol retention in the dried product, which ranged from 70.2 to 84.2% (related to the content in the extractive solution). An increase in the gum arabic to maltodextrin (DE10) ratio has positive effect on thymol retention. L. sidoides extracts and spray-dried products showed antifungal activity against tested fungal strains (Candida albicans - ATCC 64548, Candida glabrata - ATCC 90030, Candida krusei - ATCC 6258, and Candida parapsilosis - ATCC 22019), evidencing their potential as a natural antifungal agent for medicinal, food, and cosmeceutical purposes. (C) 2012 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Microencapsulation of lycopene by spray drying: Characterization, stability and application of microcapsules

Microencapsulation can be an alternative to minimize lycopene instability. Thus, the aim of this study was to microencapsulate lycopene by spray drying, using a modified starch (Capsul (R)) as an encapsulating agent, and to assess the functionality of the capsules applying them in cake. The quantity of lycopene was varied at 5, 10 and 15% in a solution containing 30% of solids in order to obtain the microcapsules. These microcapsules were evaluated as to encapsulation efficiency and morphology and then submitted to a stability test and applied in cakes. Encapsulation efficiency values varied between 21 and 29%. The microcapsules had a rounded outer surface with the formation of concavities and they varied in size. The stability test revealed that microencapsulation offered greater protection to lycopene compared to its free form and it was observed that the microcapsules were able to release pigment and color the studied food system in a homogenous manner. (C) 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.