Rice bran oil

About: Rice bran oil is a research topic. Over the lifetime, 2102 publications have been published within this topic receiving 32504 citations.

Rhizopus oryzae Lipase Immobilized on Hierarchical Mesoporous Silica Supports for Transesterification of Rice Bran Oil

Abstract: The tunable textural properties of self-oriented mesoporous silica were investigated for their suitability as enzyme immobilization matrices to support transesterification of rice bran oil. Different morphologies of mesoporous silica (rod-like, rice-like, and spherical) were synthesized and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption–desorption isotherms. The surface area, pore size, and ordered arrangement of the pores were found to influence the immobilization and activity of the enzyme in the mesopores. The immobilization in rod-like silica was highest with an immobilization efficiency of 63 % and exhibited minimal activity loss after immobilization. Functionalization of the mesoporous surface with ethyl groups further enhanced the enzyme immobilization. The free enzyme lost most of its activity at 50 °C while the immobilized enzyme showed activity even up to 60 °C. Transesterified product yield of nearly 82 % was obtained for 24 h of reaction with enzyme immobilized on ethyl-functionalized SBA-15 at an oil:methanol ratio of 1:3. Fourier transform infrared spectroscopy (FT–IR) and Gas chromatography–mass spectrometry (GC-MS) were used to characterize the transesterified product obtained. The reusability of the immobilized enzyme was studied for 3 cycles.

Analysis of quality and microstructure of freshly potato strips fried with different oils

Abstract: The quality of French fries is a key factor which affect consumer's willingness to buy it. During this study, the effects of ten commercial edible oils on the content and status of water and oil, color, texture, volumetric shrinkage and microstructure of freshly fried fries were investigated. Fries fried in rice bran oil had higher water content, volumetric shrinkage, hardness, luminosity and yellowness, as well as lower oil content and redness than those fried in other oils. Lower transverse relaxation time was observed in fries fried with high-oleic sunflower oil. Scanning electron microscopy revealed a severely damaged internal structure. Magnetic resonance imaging visualized a thicker crust in freshly fried fries. Sensory results indicated that the fries fried in rice bran oil had a superior mouthfeel and a lower oil content compared to those fried with other oils. This work can provide a useful reference for the consumers to choose appropriate oil when preparing the fries.

Production of Rice Bran Oil with Light Color and High Oryzanol Content by Multi-stage Molecular Distillation

Abstract: Color is regarded as an important quality parameter for rice bran oil (RBO). Nevertheless, numerous grade-three and grade-four RBOs with dark color are currently available in the Chinese market. These oils are usually produced by steam refining and exhibit a mahogany color, which is undesired by customers. Here, we describe the development of a new industrially viable refining method based on multi-stage molecular distillation (MMD), through which decoloration and fractionation of grade-four RBO were accomplished, and four kinds of products, pigment oil, semi-refined oil-I (SRO-I), semi-refined oil-II (SRO-II), and semi-refined oil-III (SRO-III), were obtained. The pigment oil was hazy and mahogany colored, containing 84.84 % non-triacylglycerols, mainly pigments, tocopherols, and free fatty acids. SRO-I was hazy and orange, containing 20,563 mg/kg of oryzanol (accounting for 77–82 % of raw oil) and was 28.68 % of non-triacylglycerols. In particular, higher content of monounsaturated triacylglycerols, diunsaturated triacylglycerols and non-triacylglycerols was responsible for the haze. SRO-II and SRO-III had a clear yellow appearance and a non-triacylglycerol content <1.5 %. These semi-refined oils were mixed directly after MMD and further refined by mild deacidification and winterization to obtain fully refined oil, which met the requirements of commonly used standards. Notably, the final oil exhibited light color and retained nearly 80 % of the oryzanol of raw oil. The yield of final oil reached 80–85 % through the entire refining process.

Evaluation of lubricant properties of vegetable oils as base oil for industrial lubricant

Abstract: The possible insufficiency of oil resources in the future and the poor bio-degradability of mineral oil based lubricant resulted in the need of bio lubricant. Bio-based products are typically produced from vegetable oils. For the present study rice bran oil [RBO], jatropha oil [JO] and karanja oil [KO] are selected as the base oils for the industrial lubricant. Friction and wear characteristics are evaluated on four ball tester and the initial findings show that wear scar of RBO is lowest, this is because of the presence of natural anti-oxidants like gamma oryzanol. The coefficient of friction and wear of all the oils were evaluated as per ASTM D5183 and ASTMD 4172 respectively. Viscosity of the oils are tested on Brookfield rheometer and KO is having high viscosity when compared to other two oils but the change in viscosity with temperature is low for both RBO and JO. Chemical properties of the oils are conducted as per IS: 548 (Part 1) –1964. The iodine value for KO is less when compared to RBO and JO. Less iodine value is required to impart better oxidation stability. Thermogravimetric analysis showed that RBO is stable till 320 °C and KO, JO started degrading at 200 °C. The thermal properties of all the oils are measured and RBO has shown better properties at wide range of temperatures. The disadvantages of vegetable oils like oxidative stability need to be improved by adding additives and by chemical modifications.