National Dairy Research Institute

About: National Dairy Research Institute is a facility organization based out in Karnāl, Himachal Pradesh, India. It is known for research contribution in the topics: Population & Sperm. The organization has 3228 authors who have published 3524 publications receiving 51151 citations. The organization is also known as: Imperial Institute of Animal Husbandry and Dairying & Imperial Dairy Institute.

Preparation and characterization of milk protein films and their application for packaging of Cheddar cheese.

Abstract: Casein and whey protein concentrate (WPC) films, plasticized with glycerol and sorbitol independently, were prepared by casting. The film thickness, water vapour and oxygen permeation and tensile and moisture sorption properties of the films were determined. The tensile strength (TS), tensile strain (TE) and elastic modulus (EM) of the films ranged from 0.71 to 4.58 MPa, 19.22 to 66.63 % and 2.05 to 6.93 MPa, respectively. The film properties were influenced by the type of biopolymer (casein and whey protein concentrate), plasticizer and its concentration. Increasing the plasticizer concentration, increased the film thickness, TE and water vapour permeability (WVP), but decreased the TS and EM. As the concentration of plasticizer increased to the highest level, the film thickness increased from 0.168 to 0.305 mm for glycerol-plasticized films and from 0.251 to 0.326 mm for sorbitol-plasticized films. The film thickness increased because the amount of plasticizer in the film network increased and the amount of biopolymer remained same. Casein films showed superior tensile properties as compared to WPC films. The WVP of both casein and WPC films lied between 3.87 and 13.97 g.mm./(m2.h.kPa). The moisture sorption isotherms of both films were typical of high-protein material, and were adequately described by the GAB model. The oxygen permeability of casein films was relatively lower than that of WPC films, regardless of the plasticizer used. The sensory data revealed that the organoleptic quality of Cheddar cheese was unaffected by milk-protein film packaging.

Heat stability and calcium bioavailability of calcium-fortified milk

Abstract: The objective of the study was to fortify calcium in cow milk in order to prepare calcium-enriched heat-stable milk for individuals who may not ingest enough calcium to meet minimum daily requirements. Therefore, cow milk was fortified with calcium at the rate of 50 mg/100 ml using three salts of calcium, viz. calcium chloride, calcium lactate and calcium gluconate. Upon addition of calcium salts, there was a marked drop in the pH and heat stability. However, restoration of pH to the original value with the addition of disodium phosphate stabilized the fortified milk and enhanced its heat stability over unfortified milk. The maximum in heat stability (HCT) of calcium-fortified cow milk samples remained slightly higher than that of unfortified milk. Metabolic study on mice revealed that calcium bioavailability of cow milk fortified with calcium lactate and calcium gluconate and stabilized with disodium phosphate was slightly higher than unfortified cow milk. Fortification of cow milk with calcium and restoration of its pH resulted in a calcium to phosphorus ratio still greater than one, which is considered ideal for retention of calcium in the body.

Seasonal variation in expression pattern of genes under HSP70 : Seasonal variation in expression pattern of genes under HSP70 family in heat- and cold-adapted goats (Capra hircus).

Abstract: Heat shock protein 70 (HSP70) is one of the most abundant and best characterized heat shock protein family that consists of highly conserved stress proteins, expressed in response to stress, and plays crucial roles in environmental stress tolerance and adaptation. The present study was conducted to identify major types of genes under the HSP70 family and to quantify their expression pattern in heat- and cold-adapted Indian goats (Capra hircus) with respect to different seasons. Five HSP70 gene homologues to HSPA8, HSPA6, HSPA1A, HSPA1L, and HSPA2 were identified by gene-specific primers. The cDNA sequences showed high similarity to other mammals, and proteins have an estimated molecular weight of around 70 kDa. The expression of HSP70 genes was observed during summer and winter. During summer, the higher expression of HSPA8, HSPA6, and HSPA1A was observed, whereas the expression levels of HSPA1L and HSPA2 were found to be lower. It was also observed that the expression of HSPA1A and HSPA8 was higher during winter in both heat- and cold-adapted goats but downregulates in case of other HSPs. Therefore, both heat and cold stress induced the overexpression of HSP70 genes. An interesting finding that emerged from the study is the higher expression of HSP70 genes in cold-adapted goats during summer and in heat-adapted goats during winter. Altogether, the results indicate that the expression pattern of HSP70 genes is species- and breed-specific, most likely due to variations in thermal tolerance and adaptation to different climatic conditions.

Use of various essential oils as bio preservatives and their effect on the quality of vacuum packaged fresh chicken sausages under frozen conditions

Abstract: The present study was undertaken to evaluate antimicrobial and antioxidant effect of essential oils on the quality of fresh chicken sausages. Total 15 essential oils (EOs) were screened for their antimicrobial activity; however only 9 EOs showed desired results in disc diffusion assay. It was found that four essential oils namely, clove oil (0.25%), holy basil oil (0.125%), cassia oil (0.25%) and thyme oil (0.125%) could pass sensory evaluation. Fresh chicken sausages incorporated with these EOs were vacuum packaged and stored at −18 ± 2 °C for 45 days. Control had significantly higher pH and TBARS than EO treated products and clove oil products showed least rate of increase of oxidation. Total phenolics and DPPH activity was significantly higher in treatment products than control. Treatment products showed slower rate of increase in microbial count than control and cassia oil products showed lowest microbial load at end of storage period. Regarding sensory attributes, cassia and holy basil products yielded comparably higher scores. Thus, present study indicates that all vacuum packaged frozen fresh chicken sausages were found quite acceptable even at the end of storage period of 45 days.