Influence of whey protein concentrate on the rheological characteristics of dough, microstructure and quality of unleavened flat bread (parotta)

In order to explore the possibility of using WPC as a functional ingredient in Indian traditional product – South Indian Parotta investigations were made to study the effect of replacement of wheat flour with 5, 10 and 15% WPC on the farinograph, extensograph, amylograph characteristics of wheat flour, quality of parotta and microstructure of baked parotta. The results showed an increase in farinograph stability, extensograph resistance to extension up to 10% WPC and a decrease in the farinograph water absorption, extensograph extensibility, amylograph peak viscosity, cold paste viscosity, breakdown and setback values with an increase in the level of WPC from 0% to 15%. The quality characteristics of parotta showed that the spread ratio decreased and shear force values increased significantly above 5% level. Control parotta and parotta with 5% WPC were soft, possessed thin and transparent layers whereas parottas beyond 5% WPC had thick, fused and opaque layers. The parottas with 5% WPC were rated good. The quality characteristics of parotta were adversely affected beyond 5% level of WPC. The microstructure of the top and middle layer of baked parotta with 5% WPC showed that there was a disruption in the continuity of the gluten matrix.     

Influence of enzymes on rheological,microstructure and quality characteristics of parotta—an unleavened Indian flat bread

Enzymes are used in the baking and milling industries to control dough properties and improve the quality of finished products. The role of enzymes in the baking process of an unleavened Indian flat bread, namely South Indian parotta, was studied. In this connection, comparisons have been made on the effects of different enzymes such as fungal α‐amylase (FA), glucose oxidase (GO), proteinase and xylanase on rheological characteristics and microstructure of parotta dough and its relation to the overall quality characteristics of baked parotta. Addition of GO increased, while FA, xylanase and proteinase decreased farinograph stability. Extensograph resistance to extension increased with GO or xylanase and decreased with FA or proteinase. The extensibility increased with FA, xylanase or proteinase and decreased with GO. The microstructure of parotta dough with different enzymes revealed that the use of proteinase improved the continuous gluten formation compared with the control and the other three enzymes, FA, xylanase and GO. This could be due to the proteinase enzyme breaking larger protein fibrils into smaller fibrils and thus enhancing the continuous gluten film formation. A similar observation was also noted in the microstructure of baked parotta layers. The microstructure of parotta with proteinase enzyme showed a continuous network of protein films compared with a cluster of protein films in parotta with GO. In the case of xylanase‐treated parotta, the starch granules were deformed completely and these deformed starch granules were found sticking to the protein films. In parottas prepared with GO and FA, only a few starch granules with faint outlines were visible. Generally speaking, the overall quality score of parotta decreased to 68 and 64 with the use of FA and, GO respectively, as against the control parotta score of 74. The score increased to 92 and 82 with the addition of proteinase and xylanase, respectively. Copyright © 2004 Society of Chemical Industry     

Effect of additives on the quality and microstructure of vermicelli made from<Emphasis Type="Italic"> Triticum aestivum</Emphasis>

The effects of various additives [xylanase (0.06, 0.012, and 0.018%), gluten (1.5 and 3.0%), ascorbic acid (0.01 and 0.02%), glycerol monostearate, sodium stearoyl-2-lactylate (SSL) (0.25, 0.50%) and glucose oxidase (0.1%)] on the quality of vermicelli made from Triticum aestivum was studied. The results revealed that xylanase at 0.012% produced an improved quality product in terms of increase in cooked weight, expansion in volume of strands, and firm texture without stickiness. The micrograph of vermicelli exhibited a uniform, continuous protein matrix. The yellow index values improved with addition of gluten (3%) and ascorbic acid (0.01%). The gluten added appeared as a prominent strong network in micrographs, imparting strength to the vermicelli as evidenced by higher shear values. SSL (0.5%) gave a firm, discrete product and the protein fibrils displayed a massive network, owing to the strengthening effect. At the level of glucose oxidase used (0.1%), it exerted an adverse effect on the product quality. In general, the additives lowered the cooking loss and the leaching of solids in vermicelli when compared to the control.     

Studies on highly conducting Polypyrrole/Fe3O4 nanocomposites

Polypyrrole (PPy)/Fe₃O₄ nanocomposites were in situ synthesized using chemical oxidative polymerization in an aqueous solution of FeCl₃.6H₂O, in presence of different Fe₃O₄ loadings (0%–16.52%). These composites were characterized through a 4 Probe electrical conductivity measurement technique, Fourier Transform infrared spectroscopy, energy dispersive X‐ray spectroscopy, scanning electron microscopy, X‐ray diffraction, thermo gravimetric analysis, and vibrating sample magnetometer. Results showed maximum electrical conductivity of 75.28 S/cm for the 2.52% Fe₃O₄ loaded nanocomposite and with improved thermal stability compared with the host PPy. Furthermore, a linear relationship between saturated magnetization M_s and % composition of Fe₃O₄ in the above nanocomposites was observed, showing 6.34 emu/g at 16.52% Fe₃O₄/PPy nanocomposite. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

3GPP LTE: The Future of Mobile Broadband

The mobile broadband technologies are reaching a commonality in the air interface and networking architecture; they are being converged to an IP-based network architecture with Orthogonal Frequency Division Multiple Access (OFDMA) based air interface technology. From technical perspective, fundamental goal of mobile broadband is to offer higher data rates with reduced latency. The third Generation Partnership Project (3GPP) presents the Long-Term Evolution (LTE) project in order to accommodate increasing mobile data usage and new multimedia applications. In the near future, with the recent progress made by technical specifications and vendor technology demonstrations LTE will emerge as successor to cellular systems as a broadband wireless solution. This paper provides an overview of 3GPP LTE including its history, features, technology, architecture and future. The technology components include OFDMA air-interface, Multiple-Input and Multiple-Output (MIMO) antenna technology and higher order modulation. The architecture includes Evolved Packet Core (EPC) and Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) components. This paper will concentrate to describe the main functions of the most important network elements. Also, the aim of this paper is to present the future potential of LTE which will make it an inevitable choice for wireless network operators around the globe.     

Direct laser cladding of SiC dispersed AISI 316L stainless steel

The present study concerns development of SiC dispersed (5 and 20 wt%) AISI 316L stainless steel metal-matrix composites by direct laser cladding with a high power diode laser and evaluation of its mechanical properties (microhardness and wear resistance). A defect free and homogeneous composite layer is formed under optimum processing condition. The microstructure consists of partially dissociated SiC, Cr₃C₂ and Fe₂Si in grain refined stainless steel matrix. The microhardness of the clad layer increases to a maximum of 340 VHN (for 5% SiC dispersed) and 800 VHN (for 20% SiC dispersed) as compared to 150 VHN of commercially available AISI 316L stainless steel. Direct laser clad SiC dispersed AISI 316L stainless steel has shown an improved wear resistance against diamond surface with a maximum improvement in 20% SiC dispersed AISI 316L stainless steel. The mechanism of wear was predominantly abrasive in nature.     

Influence of whey protein concentrate, additives, their combinations on the quality and microstructure of vermicelli made from Indian T. Durum wheat variety

Effect of whey protein concentrate (5%, 7.5%, 10%) and additives on the quality of vermicelli made from Indian durum wheat was studied. The results revealed that with increase in whey protein concentrate (WPC) from 0% to 10%, cooked vermicelli weight increased from 82.5 to 88 g/25 g, cooking loss increased from 6.0 to 8.4%, L values indicating lightness increased (47.42–52.9); b values indicating yellowness decreased (7.0–3.80) and shear force decreased (66–45 g). Sensory evaluation of vermicelli with 5%, 7.5%, 10% WPC showed that addition of above 5% WPC resulted in whitish colour vermicelli with mashy strand quality and sticky mouthfeel. Studies on the effect of additives namely ascorbic acid (0.01% and 0.015%), gluten (1.5% and 3.0%) and glycerol monostearate (GMS) (0.25% and 0.5%) individually as well as in combination on the quality of vermicelli with 5% WPC indicated that combination of 0.01% ascorbic acid, 3% gluten and 0.5% GMS resulted in vermicelli having lower cooking loss, creamy yellow colour, firm, discrete strands and non-sticky mouthfeel. The protein content of vermicelli with 5% WPC and combination of additives was 16% as against 11.5% of control vermicelli. Scanning electron microscopy study of control vermicelli, vermicelli with 5% WPC and vermicelli with 5% WPC and combination of additives revealed that vermicelli with 5% WPC showed a rough surface with a prominent rupture while vermicelli with 5% WPC and combination of additives showed a continuous, rupture free structure.     

Thermal diffusivity measurements in PANI and PANI-MWNT composites using photo acoustic technique

Hydrochloric acid (HCl) doped Polyaniline (PANI) and Polyaniline-Multiwalled Carbon Nano Tube (MWNT) composite samples were synthesized using chemical oxidative polymerization technique. Transmission Electron Microscopy (TEM) and Raman spectroscopy studies clearly establish the formation of PANI (HCl) and PANI (HCl)-MWNT composites. Thermal diffusivity measurements were carried out using Open Photo Acoustic Cell (OPC) technique in transmission configuration and the thermal diffusivity values were calculated. The thermal diffusivity of the composite samples is found to be greater than that of pure PANI. It increases with increase in MWNT loading upto aniline to MWNT feed ratio 1:0.3 and later decreases for the 1:0.5 sample. Still the thermal diffusivity of PANI (HCl)-MWNT composite sample is higher than that of PANI (HCl).The enhancement in thermal diffusivity is due to the high thermal conductivity of MWNT. The decrease in thermal diffusivity of the 1:0.5 sample is explained using dopant induced phonon scattering and thermal interfacial contact resistance. The present study offers ample scope for tailoring the thermal diffusivity parameters of polyaniline composites according to device requirements.     

Nano-Borides and Silicide Dispersed Composite Coating on AISI 304 Stainless Steel by Laser-Assisted HVOF Spray Deposition

The study concerned a detailed microstructural investigation of nano-borides (Cr₂B and Ni₃B) and nano-silicide (Ni₂Si) dispersed γ-nickel composite coating on AISI 304 stainless steel by HVOF spray deposition of the NiCrBSi precursor powder and subsequent laser surface melting. A continuous wave diode laser with an applied power of 3 kW and scan speed of 20 mm/s in argon shroud was employed. The characterization of the surface in terms of microstructure, microtexture, phases, and composition were carried out and compared with the as-coated (high-velocity oxy-fuel sprayed) surface. Laser surface melting led to homogenization and refinement of microstructures with the formation of few nano-silicides of nickel along with nano-borides of nickel and chromium (Ni₃B, Cr₂B, and Cr₂B₃). A detailed microtexture analysis showed the presence of no specific texture in the as-sprayed and laser-melted surface of Cr₂B and Ni₃B phases. The average microhardness was improved to 750-900 VHN as compared to 250 VHN of the as-received substrate. Laser surface melting improved the microhardness further to as high as 1400 VHN due to refinement of microstructure and the presence of silicides.