Rice-based pasta: a comparison between conventional pasta-making and extrusion- cooking

Good quality gluten-free products continue to be in demand among the celiac community and the production of pasta from non-conventional raw materials is a major technological challenge. In this work, the effects of two different pasta-making processes (conventional and extrusion-cooking) were investigated on parboiled brown and milled rice flours. The two processes differentiated for extrusion temperature (conventional extrusion: 50 C, max; extrusion-cooking: 115 C), whereas the drying diagram was the same. Starch modifications induced by each pasta-making process were analyzed by using a Micro-ViscoAmylo-graph (MVAG), Differential Scanning Calorimetry (DSC), and X-ray Diffraction. The cooking quality was evaluated by weight increase, solid loss into the cooking water, and texture analysis. Pasta obtained from milled rice using the extrusion-cooking process was characterized by the best cooking behavior. In this sample, starch presented the highest peak and final viscosities, the highest gelatinization temperature and lower enthalpy value, and the lowest crystallinity. The cooking quality of pasta obtained from brown rice appeared less affected by the processing conditions. Therefore, the nature and intensity of starch modifications can be modulated by the processing conditions and might explain the different cooking behaviour of rice pasta

Effect of iodine in semolina matrices

The effect of starch-protein interactions on the ability of linear starch chains to bind iodine was investigated in 4 types of semolina. Based on K/S (absorption/scattering coefficient) spectra, obtained after equilibration above K 2SO 4 and exposure to iodine vapor, and X-ray diffraction, semolina samples showed differences in chain mobility, iodine-binding capacity and crystalline order. After removing protein from the samples, starch exhibited a higher iodine-binding capacity, suggesting greater starch chain mobility, and low crystalline order. The results suggest that protein and/or starch-protein affect the packing arrangement of starch polymers within the granule

Evolutionary dynamics on strongly correlated fitness landscapes

We study the evolutionary dynamics of a maladapted population of self-replicating sequences on strongly correlated fitness landscapes. Each sequence is assumed to be composed of blocks of equal length and its fitness is given by a linear combination of four independent block fitnesses. A mutation affects the fitness contribution of a single block leaving the other blocks unchanged and hence inducing correlations between the parent and mutant fitness. On such strongly correlated fitness landscapes, we calculate the dynamical properties like the number of jumps in the most populated sequence and the temporal distribution of the last jump which is shown to exhibit a inverse square dependence as in evolution on uncorrelated fitness landscapes. We also obtain exact results for the distribution of records and extremes for correlated random variables

A New Look At Management Accounting

This paper presents a comparison of the traditional management accounting with the new approach of management accounting with the use of latest information technology and manufacturing technologies.  The information and data of the research were gathered from various sources of secondary data. Many online articles and journals were available through these search engines such as Google, Infoseek, Lycos, Excites and Altavista. These articles were downloaded from Internet Websites including IFAC library, CPA online newsletters, Institute of Management Accountants, CIMA (Chartered Institute of Management Accountants), Technical Bulletin and Institute of Commercial and Financial Accountants.  The modern techniques used in Management Accounting are discussed. TQM (Total Quality Management), ABC (Activity Based Costing) and BSC (Balanced score card) are some of the tools that are introduced in management accounting to keep up with the latest technology.  This research highlights the emergence of new, more proactive management accounting that increasingly becomes part of the management team with the business process. The future roles and expectations of these accountants in the competitive global economy are discussed

Number of adaptive steps to a local fitness peak

We consider a population of genotype sequences evolving on a rugged fitness landscape with many local fitness peaks. The population walks uphill until it encounters a local fitness maximum. We find that the statistical properties of the walk length depend on whether the underlying fitness distribution has a finite mean. If the mean is finite, all the walk length cumulants grow with the sequence length but approach a constant otherwise. Experimental implications of our analytical results are also discussed

Characteristics of Perennial Wheatgrass (Thinopyrum intermedium) and Refined Wheat Flour Blends: Impact on Rheological Properties

Intermediate wheatgrass (IWG) (Thinopyrum intermedium) is a perennial grass with desirable agronomic traits and positive effects on the environment. It has high fiber and protein contents, which increase the interest in using IWG for human consumption. In this study, IWG flour was blended with refined wheat at four IWG-to-wheat ratios (0:100, 50:50, 75:25, and 100:0). Samples were analyzed for proximate composition, microstructure features, pasting properties (Micro Visco-Amylo-Graph device), protein solubility, and total and accessible thiols. Gluten aggregation properties (GlutoPeak tester) and mixing profile (Farinograph-AT device) were also evaluated. IWG flour enrichment increased the pasting temperature and decreased the peak viscosity of blended flours. IWG proteins exhibited higher solubility than wheat, with a high amount of accessible and total thiols. The GlutoPeak tester highlighted the ability of IWG proteins to aggregate and generate torque. Higher IWG flour enrichment resulted in faster gluten aggregation with lower peak torque, suggesting weakening of wheat gluten strength. Finally, the addition of IWG to refined wheat flour resulted in a decrease in dough development time and an increase in consistency, likely because of the higher levels of fiber in IWG. The 50% IWG flour enrichment represents a good compromise between nutritional improvement and maintenance of the pasting properties, protein characteristics, and gluten aggregation kinetics

Structural modification of gluten proteins in strong and weak wheat dough as affected by mixing temperature

The effects of temperature ( 6525\ub0C) on dough rheological properties and gluten functionality have been investigated for decades, but no study has addressed the effect of low temperature (<30\ub0C) on gluten network attributes in flours with strong and weak dough characteristics. This study monitored changes in protein extractability in the presence and absence of reducing agents, the contents of readily accessible and SDS-accessible thiols, and the secondary structural features of proteins in doughs from commercial hard wheat flour (HWF) and soft wheat flour (SWF) mixed at 4, 15, and 30\ub0C. SWF mixed at 4 and 15\ub0C showed similar mixing properties as HWF mixed at 30\ub0C (which is the standard temperature). The effect of mixing temperature is different at the molecular level between the two flours studied. Protein features of HWF did not change as mixing temperature decreased, with the only exception being an increase in SDS-accessible thiols. Decreasing mixing temperature for SWF caused an increase in SDS protein solubility and SDS-accessible thiols as well as an increase in \u3b2-turn structures at the expense of \u3b2-sheet structures. Thus, noncovalent interactions appear to drive protein network at low temperatures (4 and 15\ub0C), whereas covalent interactions dominate at standard mixing temperature (30\ub0C) in doughs from both flours

Temperature‑induced changes in dough elasticity as a useful tool in defining the firmness of cooked pasta

Semolina with high protein content and strong gluten is recognized as the best raw-material for pasta-products with a good cooking quality, while little consideration has been given to semolina dough elasticity when heating is applied. In this research, a new technique was developed by adapting the Glutograph (Brabender GmbH&Co., Duisburg, Germany) to measure the changes in elasticity induced by heating on a sheeted dough. The information obtained by this procedure was related to the firmness of cooked pasta. Starting from semolina of four durum wheat varieties with differences in protein quantity and quality, dough samples were prepared in a Farinograph at a hydration level of 35 %. Each dough was sheeted by a home-made pasta machine, obtaining disks of 5 cm diameter and 2.1 mm thickness. Stretching (10 s) and relaxation (30 s) cycles were applied repeatedly during the test time, while dough temperature was increased from 30 to 90 °C at 1.2 °C/min. For each peak recorded, stretching and recovery values were calculated and plotted against sample temperature. Both stretching and recovery curves were integrated and the loss of elasticity was calculated. Results showed as high elasticity loss during heating is related to low firmness of the related cooked pasta