Characteristics Of Rice Flour Research Articles

Physicochemical Characteristics of Rice Flour Developed as Rice Powder and Quality Characteristics of Rice Cakes

Physicochemical Characteristics of Rice Flour Developed as Rice Powder and Quality Characteristics of Rice Cakes

Characteristics of Rice Flour Suitable for the Production of Rice Flour Bread Containing Gluten and Methods of Reducing the Cost of Producing Rice Flour

3 Niigata Agricultural Research Institute Food Research Center (Kamo, Niigata 959-1381, Japan) Abstractproduction of various rice flour-based food products such as bread, noodles, and cakes is expect- ed to increase the consumption of rice and the utilization of rice paddies in Japan. This paper reviews studies conducted on the characteristics of rice flour and the rice cultivars suitable for the production of rice flour bread containing gluten. The challenges of reducing the cost of producing rice bread are also reviewed. The production of rice flour bread containing gluten of a highly specific loaf volume requires the use of rice flour with a low damaged starch content that can be produced by jet milling wet rice after water or enzyme treatment. The amylose content of rice flour affects the quality of bread, including its shape and hardness. Rice flour with an amylose content of 16% to 20% forms a chewy and moderately soft bread. When rice flour with a low damaged starch content (less than 5%) and a desirable amylose content (16% to 20%) is used, the production of rice flour bread containing gluten is easy without being different from how wheat flour bread is made. In order to reduce the cost of producing rice flour, high-yielding cultivars or a pin milling system using floury rice cultivars should be employed; high-yielding cultivars are now being used for the production of rice flour. With the pin milling system, rice flour belonging to the floury rice cultivar has a low damaged starch content. However, there is a need to develop a high-yield floury rice with reduced weight loss during polishing, as well as new polishing processes. Furthermore, the production of brown rice flour con- tributes to reducing the cost of producing rice flour because no polishing process is required. Brown rice flour with a low damaged starch content can be produced using a jet mill after soaking for more than 12 h. And given its favorable high nutritional properties, bread made from brown rice flour will prove appealing to consumers. Despite expectations of increasing of the consumption of rice through the use of rice flour as in the production of rice flour bread, the cost reduction of rice flour produc- tion and the development of delicious rice flour bread desired by consumers are still insufficient. By understanding the requirements of bread-making companies and obtaining a deeper knowledge about the quality characteristics of rice flour, such as amylose content and protein composition, the produc- tion of rice flour bread appealing to consumers can be expected.

The Effect of Variety and Processing Methods on the Functional and Chemical Properties of Rice Flour

The effect of varieties, local (Abakalike) and foreign (Mama Gold) and two processing methods, semi-dry and wet grinding methods on the characteristics of rice flour were investigated. Functional and chemical properties of the rice flour were analyzed using standard methods. The functional parameters analyzed were dispersibility, relative bulk density, swelling power and water absorption capacity while chemical parameter were moisture content, protein, ash, sugar, starch, amylase and amylopectin. The parameters were influenced by variety and processing methods. Highest dispersibility, relative bulk density and swelling power values were associated with sample A which is the foreign variety, while solubility and water absorption capacity were associated with sample B, which is the local variety, all processed by the semi-dry grinding method. The semi-dry ground rice flour produced highest protein and ash as seen in sample B, while wet milled rice flour were associated with highest moisture and starch contents. The flour produced from the local rice (Abakalike) had highest protein, ash sugar and amylose over the foreign variety with all the parameters showing significant differences.

The impact of germination on the characteristics of brown rice flour and starch

In recent years, germinated brown rice as a functional food has received great attention with its improved sensory and nutritional properties. Particularly of interest are the high levels of γ-amino butyric acid (GABA) which can be obtained during germination. However, more studies are needed to fully understand the effect of germination on the physicochemical properties of brown rice. Germination altered the chemical composition of brown rice, resulting in an increase in reducing sugar and ash content, and a reduction in amylose. Solubility, paste viscosity, transition temperatures (T(o) , T(p) and T(c) ) and percentage of retrogradation (%Retrogradation) were decreased, while swelling power and turbidity were significantly increased. Scanning electron micrographs indicated that starch granules from germinated brown rice became smaller and less homogeneous. Moreover, germination shortened the chain length of amylopectin and amylose molecules. This investigation provides information on changes in the characteristics of rice flour and rice starch during germination, leading to a better understanding on the chemistry of brown rice germination.

Moisture sorption characteristics of rice flour.

Moisture equilibrium data (adsorption and desorption) of rice flour were determined using the static gravimetric method of saturated salt solutions at three storage temperatures: 10, 20 and 30 degrees C. The range of water activities for each temperature was from 0.11 to 0.85. Equilibrium moisture content decreased with increase in storage temperature at any given water activity. The experimental data were fitted to four mathematical models (modified Oswin, modified Halsey, modified Chung-Pfost and modified Henderson). The monolayer moisture content was estimated from sorption data using the Brunauer-Emmett-Teller (BET) equation. The isosteric heats of sorption were evaluated using Clausius-Clapeyron equation.