GOPIRAJAH RAJAMANICKAM
@generalmills.co.in
Scientist
General Mills India Ltd
EDUCATION
PhD in Food Science
RESEARCH, TEACHING, or OTHER INTERESTS
Food Science, Chemical Engineering, Agricultural and Biological Sciences, General Agricultural and Biological Sciences
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Sumera Javad, Rajamanickam Gopirajah, and Syed S.H. Rizvi
Elsevier BV
Tina Ying Pan, Rajamanickam Gopirajah, Sugirtha Krishnamurthy, and Syed S.H. Rizvi
Wiley
AbstractA correlation model for predicting the maximum product temperature reached during a supercritical fluid extrusion (SCFX) process was developed using the Buckingham Pi method. Two dimensionless groups, Dref (ratio of screw diameter to screw length) and Eref (ratio of energy added to energy removed), were developed to model the maximum temperature of an SCFX process using dimensional analysis. The model was validated by comparing predicted and experimental values. Experiments were conducted using two feed formulations: 1. Milk protein concentrate (MPC) with rice flour (30%), and 2. MPC with grape pomace (15%). The average percent error was 2.57% for rice flour extrudate and 1.02% for grape pomace extrudate. Based on the results, the model could be used for prediction of maximum temperature in SCFX systems.Practical ApplicationsMaintaining the extruder temperature below 100°C remains a major challenge during the supercritical fluid extrusion (SCFX) process. The model developed determines the maximum temperature of a given SCFX system based on key extrusion parameters. Hence, the developed model can be used by manufacturers for determining the optimal operating conditions while scaling up an SCFX process.
Rajamanickam Gopirajah, Poonam Singha, Sumera Javad, and Syed S. H. Rizvi
Hindawi Limited
Sumera Javad, Rajamanickam Gopirajah, and Syed S. H. Rizvi
Wiley
AbstractSupercritical fluid extrusion (SCFX) with carbon dioxide was used to enhance the functionality of whey protein concentrate containing 80% protein by weight (WPC80) at two (3.0 and 5.4) pH values. Different levels of oil (20, 40, 60, and 80% by weight) and functionalized whey protein (f‐WPC80; 1, 2, and 4% by weight) were used to make emulsions and quantify their characteristics such as emulsion activity index, creaming index, droplet size, and viscosity. Unextruded whey protein (c‐WPC80) and commercial sodium caseinate (NaCas) were used as controls. Results showed that gel‐like emulsions with uniform droplet size distributions were formed by f‐WPC80 (4% by weight) with 80% (by weight) oil which was stable over 3 months of storage at room temperature. Compared to emulsions formed by control c‐WPC80, the f‐WPC80 emulsions exhibited higher viscosity and shear thinning behavior. The minimum protein required for stable emulsion formation (with 80% oil) was found to be 2% by weight for f‐WPC80 and NaCas and 4% by weight in the case of c‐WPC80. The functionalized whey protein provided a better emulsion at low concentrations with good stability at room temperature and may be used as a replacement of sodium caseinate to make nutritionally superior products.Practical applicationsPresent study showed that functionalized Whey protein concentrate (80% protein) f‐WPC80 was produced by the process of Supercritical carbon dioxide assisted extrusion which changed the structure of native protein. Two functionalized products (with pH 3.0 and 5.4) were obtained in this way. These functionalized proteins formed better oil‐in‐water emulsions which were stable against creaming and sedimentation as compared to emulsions stabilized by native WPC80 and sodium caseinate at very small concentration of protein used. Therefore it is concluded that f‐WPC80 can cover a range of food emulsions where different pH values are required. Lesser amount of stabilizer will be used commercially for emulsions. These functionalized WPC80 products may be used as a replacement of sodium caseinate to make nutritionally superior products with pH 3.0 and 5.4.
Rajamanickam Gopirajah and Kasiviswanathan Muthukumarappan
Hindawi Limited
R. Gopirajah, Keshav Prakash Raichurkar, Rajkumar Wadhwa, and C. Anandharamakrishnan
Royal Society of Chemistry (RSC)
The chief motor functions of human stomach, namely receiving, storing, mixing and emptying, influence the absorption of ingested food and hence determine the glycemic response to the meal.
R. Gopirajah and C. Anandharamakrishnan
Springer Science and Business Media LLC
J. Aprajeeta, R. Gopirajah, and C. Anandharamakrishnan
Elsevier BV
Dibyakanta Seth and Gopirajah Rajamanickam
Wiley
SummaryResponse surface methodology (RSM) based on a five‐level‐three‐factor central composite rotatable design (CCRD) was employed for optimisation of formulation for production of a soy‐fortified millet‐based extruded snack. Effects of amount of ingredients such as ragi (40–50%), sorghum (10–20%) and soy (5–15%) on the physical properties like bulk density, expansion ratio, water absorption index and water solubility index of snacks were investigated. Significant regression models that explained the effects of different percentages of ragi, sorghum and soy on all response variables were determined. The coefficients of determination, R2, of all the response variables were higher than 0.90. Based on the given criteria for optimisation, the basic formulation for production of millet‐based extruded snack with desired sensory quality was obtained by incorporating with 42.03% ragi, 14.95% sorghum, 12.97% soy and 30% rice.