Development of monoclonal antibody based sandwich ELISA for the rapid detection of pathogenic Vibrio parahaemolyticus in seafood

Thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) are considered important virulence factors of Vibrio parahaemolyticus and strains producing either of these or both are considered pathogenic. In this study, we generated monoclonal antibodies (mAbs) against purified TRH recombinant protein of pathogenic V. parahaemolyticus. Sandwich enzyme-linked immunosorbent assays (ELISA) using the hybridoma clone 4B10 showed higher sensitivity of detection compared to other clones. Using mAb 4B10 based sandwich ELISA, we could detect pathogenic V. parahaemolyticus in 41.18% (14 out of 34) of the seafood samples analyzed. PCR targeting the toxR gene showed the presence of V. parahaemolyticus in 64.7% (22 out of 34) seafood samples. Further, PCR targeting the virulence genes showed that 6 seafood samples harboured the tdh gene while 9 harboured the trh gene indicating the presence of pathogenic V. parahaemolyticus. Our results show that mAb 4B10 sandwich ELISA developed in this study could be used as a rapid method for screening seafood samples for the presence of pathogenic V. parahaemolyticus.     

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.     

Effect of partially defatted coconut flour on the rheological,physico-sensory characteristics and fatty acid profile of no-added fat rusk

Partially defatted coconut flour (PDCF) as a source of medium chain fatty acids was selected to replace fat in rusk formulation. Effect of replacement of wheat flour with PDCF (10%, 20% and 30%) on quality characteristics of rusk was studied. Increasing PDCF from 0% to 30% decreased farinograph water absorption, amylograph peak viscosity and overall quality score (52.5 to 19.5) of rusk. Use of additive mix, AM (4% dry gluten powder + 0.002% fungal α-amylase) to 20% PDCF, increased the farinograph dough stability, strength of the paste during heating and overall quality score (39.5 to 50.5). The rusk with 20% PDCF + AM was stable up to 30 days, had 1.6, 5.5 times higher protein and dietary fibre contents as compared to control rusk respectively. The fat in the rusk had zero trans fatty acids and contained 66.2% medium chain fatty acids with lauric acid as a major fatty acid.     

Effect of multigrains on rheological, microstructural and quality characteristics of north Indian parotta - An Indian flat bread

Effect of replacement of whole-wheat flour with multigrain blend, MGB (chick pea split without husk, barley, soya bean and fenugreek seeds) at 10, 20, 30 and 40 g/100 g on rheological characteristics of whole-wheat flour and quality of north Indian parotta (NIP) making was studied. Use of increasing amount of MGB from 0 to 40 g/100 g increased farinograph water absorption, decreased dough stability, extensograph resistance to extension, extensibility, amylograph peak viscosity and overall quality score of NIP from 53 to 38 for the maximum score of 60. Use of combination of dry gluten powder, sodium stearoyl-2-lactylate and hydroxypropylmethylcellulose separately and in combination significantly improved the overall quality of NIP with 30 g/100 g MGB. Addition of multigrains increased the protein, fat, dietary fiber and mineral contents of north Indian parotta.     

Entanglement of formation is non-monotonic with concurrence: a simple proof

In this paper we explore the non-monotonic nature of entanglement of formation with respect to concurrence for pure bipartite states. For pure bipartite system, one of the basic physical reason of this non-monotonicity character is due to the existence of incomparable states, i.e., the pure bipartite states which are not convertible to each other by LOCC with certainty.      

Effect of chemical composition of wheat flour and functional properties of dough on the quality of south Indian parotta

Six flours differing in quality were analysed for their chemical and rheological parameters. South Indian parottas were prepared and evaluated for their textural characteristics using an Instron universal testing machine (UTM) and their sensory characteristics by a trained panel. The correlation coefficient data indicated that among the chemical characteristics of flours, dry gluten, protein and SDS sedimentation value were found to be the best indices in predicting the quality of parotta. The rheological characteristics, such as farinograph water absorption, extensograph ratio figure and area, and Instron apparent biaxial extensional viscosity (ABEV), hardness and cohesiveness were found to be highly correlated to the overall quality score of parotta. Sensory texture of parotta was found to be highly correlated to shear force as well as compression force (r=0.99, P ≤ 0.001) indicating that shear and compression forces could be considered as the best indices of sensory texture of parotta.     

Saccharomyces unisporus: Biotechnological Potential and Present Status

The yeast species of the Saccharomyces genus have a long history of traditional applications and beneficial effects. Among these presence of the Saccharomyces unisporus has been documented in various dairy products and has become a subject of interest and great importance. S. unisporus has shown a significant role in the ripening of cheese and production of fermented milk products such as kefir and koumiss. The absence of pseudohyphae during the life cycle of S. unisporus is an indication of nonpathogenicity. Significance has been laid on the presence of S. unisporus in food‐grade products and a close proximity of S. unisporus to S. florentinus and both of these species are accepted by the International Dairy Federation and the European Food and Feed Cultures Association for food and feed applications. Since over the years, S. unisporus has already become a part of various dairy products, S. unisporus can be considered as a potential candidate for generally regarded as safe status. S. unisporus has the capacity to convert ketoisophorone to levodione, which is an important pharmaceutical precursor. S. unisporus are considered as the potential producers of farnesol which eventually controls filamentation of pathogenic microorganisms. Apart from that, S. unisporus produces certain omega unsaturated fatty acids which combat diseases. Henceforth, the areas which S. unisporus can be possibly exploited for its useful intermediates are the enzymes and fatty acids it produces. In this context, this review attempts to describe and discuss the ubiquity of S. unisporus in food products, cellular composition, regulatory pathways, and its synthesis of fatty acids and enzymes.     

An investigation of bread-baking process in a pilot-scale electrical heating oven using computational fluid dynamics

A computational fluid dynamics (CFD) model was developed for bread-baking process in a pilot-scale baking oven to find out the effect of hot air distribution and placement of bread on temperature and starch gelatinization index of bread. In this study, product (bread) simulation was carried out with different placements of bread. Simulation results were validated with experimental measurements of bread temperature. This study showed that nonuniform air flow pattern inside the oven cavity leads to uneven temperature distribution. The study with respect to placement of bread showed that baking of bread in upper trays required shorter baking time and gelatinization index compared to those in the bottom tray. The upper tray bread center reached 100 °C at 1200 s, whereas starch gelatinization completed within 900 s, which was the minimum baking index. Moreover, the heat penetration and starch gelatinization were higher along the sides of the bread as compared to the top and bottom portions of the bread.     

Effect of hydrocolloids and emulsifiers on the rheological,microstructural and quality characteristics of eggless cake

Effect of hydrocolloids like Arabic (AR), guar (GR), xanthan (XN), carrageenan (CG) and hydroxypropylmethylcellulose (HPMC) in combination with emulsifiers such as glycerol monostearate (GMS) and sodium stearoyl-2-lactylate (SSL) on the rheological, microstructural and quality characteristics of eggless cake was studied. Addition of GR to wheat flour in the presence of SSL increased peak viscosity, while in the presence of GMS all hydrocolloids excepting XN increased the peak viscosity. The set back value decreased with the addition of hydrocolloids. Addition of hydrocolloids to wheat flour as well as in the presence of GMS and SSL increased the eggless cake batter viscosity, specific gravity, and XN showed the highest value. Among different hydrocolloids tried, only HPMC improved the eggless cake making characteristics of wheat flour. Use of HPMC increased the overall quality score of eggless cake with GMS to the maximum extent followed in decreasing order by CG and XN. Addition of all the hydrocolloids increased the overall quality of eggless cake with SSL and highest improvement was brought about by HPMC. Microstructure studies of eggless cake crumb with hydrocolloids showed that the starch granules appeared wrapped by XN and HPMC. In eggless cake with combination of HPMC and SSL the protein matrix appeared more uniform.