This study examines the supercritical carbon dioxide (SC-CO(2)) extraction of oryzanols contained rice bran oil from powdered rice bran. The extraction efficiencies and concentration factors of oryzanols, free fatty acids and triglycerides in the SC-CO(2) extracts were determined. With top-flow type SC-CO(2) extraction the total oil yield was 18.1% and the extraction efficiencies of oryzanols and triglycerides were 88.5 and 91.3% respectively, when 2750 g CO(2 )was consumed during the extraction of 35 g rice bran powder. The concentration factors of oryzanols and triglycerides in SC-CO(2)-extracted oil were higher than in the Soxhlet n-hexane extracted oil. SC-CO(2) extractions indicated that pressure can be used more effectively than temperature to enhance the extraction efficiency and concentration factor of oryzanols. A two-factor central composite scheme of response surface methodology was employed to determine the optimal pressure (300 bar) and temperature (313 K) for increasing the concentration of oryzanols in the SC-CO(2) extracted oil.

Designing supercritical carbon dioxide extraction of rice bran oil that contain oryzanols using response surface methodology.

Six particle size fractions were prepared by grinding and sieving stabilized hard red wheat bran, oat fiber, and corn bran. Water adsorption indices (WAI's) and effective diffusion coefficients (D eff ) were measured for all size fractions. WAI's of wheat bran decreased with particle size. WAI's of oat bran increased as particle size decreased and the WAI's of corn bran fractions did not vary as much as the other fibers. The D eff 's of wheat increased, of oat decreased, and of corn were about the same as the particle size decreased. The wheat D eff was less than that of corn which was less than that of oats. Monolayer moisture content and bulk moisture content at high A w were determined from moisture sorption isotherms measured on the smallest particles. There was no difference in the monolayer moistures but both corn and wheat brans adsorbed much more water at high A w than did the oat bran. Effect of particle size on water sorption and, by inference, some types of functionality cannot be generalized and must be determined for each type of fiber. L'addition de fibres alimentaires a des aliments transformes, pour developper des produits enrichis en fibres, est limitee par les caracteristiques de sorption de l'eau des fibres. Cette etude evalue la taille des particules qui correspond a la sorption d'eau minimale de 3 types de fibres alimentaires communes: sons de ble, d'avoine et de mais, stabilises. La taille des particules influence la sorption de l'eau pour le son de ble et d'avoine, pas pour le mais. L'adsorption d'eau de chaque type de fibre depend de la composition de la particule.

Effect of particle size on the water sorption properties of cereal fibers

Analysis of moisture sorption characteristics of fish protein myosin

Sugar is a natural food, which fulfills all the physiological functions of a carbohydrate food. It provides calories and combines with many valuable
foods to enhance their taste appeal. It remains the major sweetener in foods especially traditional sweets. Sweetness is an attractive quality in foods. However, sugar has become a subject of controversy over its adverse effects
in health and nutrition namely as a contribution to excessive calories, diabetes, hyperglycemia, hypertension and as a principal causative factor of dental carries.
Growing awareness of each of these issues has cast a negative influence on the consumer towards sucrose based foods and the demand for low or no sugar products is on the increase. Thus today there exists a need to provide low sugar or sugar free products, which have characteristics similar to those of sugar. However there are problems in replacing sugar with alternatives. This is because sugar in addition to sweetness, imparts many desirable characteristics to the product like body and texture. It is also a good preservative. Sucrose alternatives should naturally satisfy these requirements. Many types of sucrose alternatives are now available and with the help of
these, tailor made foods can be prepared so that consumers are not penalized with excessive calories. The main aim of the present study was to replace sugar in Indian sweets with sucrose alternatives, without affecting the
desirable quality attributes of these products. With this broad aim in view, the work was initiated on selected Indian sweets such as jamun, burfi, laddu and the results are presented in these studies.

Studies on the use of Sucrose Alternatives in Traditional Sweetmeats

Water activity and equilibrium moisture data of full-fat and defatted rice bran protein concentrate powder at a fixed temperature of 27°C were obtained from apparatus designed for the purpose. The data were analysed for the determination of values of bound water, water activity for the maximum stability, moisture content at the change over points in the nature of moisture binding and energy required for the removal of bound water in these materials. BET, Caurie, Stability, «Local», and «GAB» isotherm models were used for analysing the data. Rice bran protein concentrates were found to be stable for storage in the water activity ranges of 0.2 to 0.4 and 0.35 to 0.36, which correspond to the equilibrium moisture contents of 2.8 to 3.8 and 3.2 to 3.7% respectively, for full-fat and defatted samples

M. B. Bera

Papers

Moisture adsorption characteristics and storage stability of rice bran protein concentrate.