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ThesisItem Open Access MANUFACTURE OF PROCESSED CHEESE USING RENNET CURD FROM ULTRAFILTRATION RETENTATE(ICAR-NDRI, KARNAL, 2022) SURESH C T; Yogesh KhetraThe cheese market in India reached a value of INR 44.8 billion in 2020 and expected to grow annually by 24.80 % during 2021-2026. Processed cheese has been one of the most dynamically growing segments of the food industry and the most consumed cheese variety in India. It contributes approximately 45 % of the total cheese market. Over the past ten years, there has been a sharp growth in processed cheese production, consumption and trade due to its more enticing flavour profile and versatility at much more economical price than other types of cheese available in the market. Natural cheese being major ingredient in manufacturing of processed cheese involves high cost during production and ripening which reflects in the final price of processed cheese produced. As a new approach, the present study was done to manufacture processed cheese using rennet curd obtained from ultrafiltration (UF) retentate. UF of skim milk resulted in reduction in flux with a mean flux value of 0.46 kg/m2min. Processed cheese was prepared using rennet curd (moisture 59.75±0.31 % w/w; protein 35.09±0.43 % w/w), butter (fat 84.50±0.50 % w/w), NaCl (@ 2 %) and different emulsifying salts (@ 3 %). Twenty one processed cheese samples from seven different emulsifying salts (in individual and in blend of binary or ternary) with three different extents of hydration (0, 60 & 120 min) were prepared and the optimization was done in comparison to the control processed cheese (CPC) prepared from natural Cheddar cheese. Processed cheese prepared from rennet curd (RPC) was having proximate composition comparable to CPC with respect to moisture, fat and protein. The prepared slurry was analysed for pH and % soluble calcium (SC) and it was found that type of ES and hydration time had significant (P<0.05) effect on slurry pH and SC. Hydration resulted in increased SC in case of Salt A, blend of Salt A with Salt B and in the blend of Salt B and Salt C, but for other salts, it reduced upon hydration. The change in SC resulted in significant (P<0.05) changes in textural, functional and rheological properties of RPC. Increase in SC resulted in increase in hardness and melt properties (meltability and flowability) of RPC prepared from Salt A, but in the case of phosphate-based ES, decrease in SC upon hydration resulted in reduction in hardness and increased melt properties due to improper emulsification of fat. The type of ES and hydration affected the rheological parameters and were in agreement with meltability (damping factor) and hardness values (storage and loss modulus). CPC had less hardness (41.20±1.58 N) and more meltability (6.57±0.73) as compared to all RPCs prepared. The Salt A at 60 min hydration had melt properties close to CPC and thus was selected as optimised cheese matrix for flavour incorporation at different levels of enzyme modified cheese (EMC). Confocal microscopy confirmed the improved fat emulsification in RPC prepared from Salt A at 60 min hydration as compared to unhydrated sample (Salt A-0) and CPC. Optimised processed cheese incorporated with 3 % EMC along with CPC were analysed during storage of 35 days for physico-chemical, textural, functional, rheological and colour values at an interval of 7 days at 5±1 °C. Storage of both samples resulted in significant (P<0.05) changes in physico-chemical properties viz. moisture, pH, acidity, water activity, tyrosine value, degree of hydrolysis, acid degree value and TBA value. Sensorial, textural, functional, rheological, colour values and microbiological quality of cheese samples were affected during storage period. Optimised processed cheese can be produced at 7.84 % lesser cost as compared to control cheese. Hence in comparison with conventional processed cheese, UF rennet curd can be selected as a replacement for matured cheese to manufacture processed cheese at reduced cost with better stability.ThesisItem Open Access DEVELOPMENT OF GHEE RESIDUE INCORPORATED DAIRY SPREAD(ICAR-SRS-NDRI, KARNAL, 2022) ABHISHEK SINGH KANWAR; MONIKA SHARMAGhee residue, a nutrient dense mass obtained as a by-product during the preparation of ghee has not been effectively utilized for food product development. Present study was planned to optimize the formulation and processing conditions of ghee residue incorporated dairy spread. Levels of ghee residue (10-20%), chhana (10-15%), butter (15-25%), whey powder (8-12%) and sodium tripolyphosphate (STPP) (0.5-1.5%) were optimized using I- optimal mixture design. Sensory scores, pH, acidity, total solids and textural parameters of the spread were recorded. The polynomial models fitted well to sensory and textural parameters with R2 values in the range 0.70 – 0.86. The optimized formulation of the developed dairy spread has a desirability of 0.89. After formulation optimization, the processing parameters were optimized using response surface methodology. Cooking time, homogenization speed and mixing time varied from 2-5 min, 10000-20000 rpm and 1-5 minutes, respectively during optimization. The overall sensory acceptability increased with increasing speed of high shear mixer. Upon optimization, the desirability for the obtained solution was 0.91, which was further validated by comparing the predicted and actual values. The optimized product recorded 52.34% moisture, 22.49% fat, 5.86% protein and 2.1% ash content with a storage life of 30 days at refrigeration temperature. During 30 days storage, acidity, oiling off, thiobarbituric acid value and tyrosine value increased from 0.382 to1.082% lactic acid, 4.0 to 4.7%, 0.197 to 0.225mg malonaldehyde/kg, 42.43 to 75.04 ug/g, respectively. Further, the consumer acceptance study revealed that 100% consumers liked the product. Microbial load of the product such as SPC, coliform and yeast and mold count were 3.96cfu/g, 1.78cfu/g and absent/g respectively.Thus, it can be concluded that a sensorially acceptable dairy spread could be successfully developed using ghee residue as an ingredient.ThesisItem Open Access Isolation and characterization of proline-rich peptides from Indian indigenous cow colostrum(ICAR-NDRI, KARNAL, 2022) MAMTA KUMARI; Shaik Abdul HussainThe present investigation was aimed to isolate and characterize a group of peptides known as Proline rich peptides (PRP) or Colostrinin from Indian Indigenous cow colostrum. PRP was isolated from colostrum of three indigenous cow breeds viz. Gir, Sahiwal and Tharparkar and a cross breed Karan Fries, at different milking intervals (1, 12, 24, and 36 h postpartum). The compositional variation of colostrum with milking interval showed that colostrum of Indigenous breeds except for Fat, had significantly (P<0.05) higher Protein, Lactose, Salt and Total solids content than crossbreed. Except for lactose all the other parameters were maximum in the first milking hour, while they decreased significantly (P<0.05) as milking intervals proceeded postpartum. Protein (% w/w) was highest in Gir colostrum (16.1±0.02% w/w) and lowest in Karan Fries (15.10±0.06% w/w) at 1 h postpartum. PRP isolation was optimized using membrane filtration and two different PRP fractions viz. 10 kDa and 3 kDa peptide fractions obtained were analysed for variation among breeds with respect to milking intervals. Peptide content was highest at 1 h postpartum and decreased significantly (P<0.05) upto 36 h postpartum. Peptide content was highest in Gir (0.310±0.002 mg/ml; 0.192±0.002 mg/ml) and lowest in Karan Fries (0.265±0.002 mg/ml; 0.161±0.003 mg/ml) in 10 kDa and 3 kDa peptide fractions, respectively at 1 h postpartum. SDS-PAGE analysis of 10 kDa and 3 kDa peptide fractions at 1h and 12 h postpartum, showed the presence of PRP’s. Functional properties of PRP revealed that samples obtained after 1 h postpartum had higher activity than those obtained at 12 h postpartum. ACE inhibitory activity was highest in Gir (84.2±0.796; 80.7±1.04) and lowest in Karan Fries (69.1±1.59; 58.3±2.39) in 10 kDa and 3 kDa fractions, respectively. IC50 value (ABTS) was lowest for Gir (141.11 μg/ml; 219.58 μg/ml) followed by Tharparkar (142.55 μg/ml; 261.44 μg/ml), Sahiwal (172.24 μg/ml; 311 μg/ml) and Karan Fries (268.26 μg/ml; 457.29 μg/ml) in 3 kDa and 10 kDa fractions, respectively at 1 h postpartum. Qualitative analysis of phagocytic activity in PRP showed the peritoneal macrophages actively showing phagocytic activity in the presence of PRP’s. Lymphocyte proliferation index of PRP showed that Karan Fries (1.59±0.083) had pro-inflammatory activity, while Gir (1.21±0.024), Sahiwal (1.16±0.045) and Tharparkar (1.17±0.032) had moderate pro- and better antiinflammatory activity at 1 h postpartum. From the present investigation, it was concluded that PRP from Indian indigenous cow colostrum has superior functional attributes viz. ACE inhibitory activity, antioxidant activity and immunomodulatory properties compared to the PRP obtained Karan Fries cow.ThesisItem Open Access STUDIES ON GHEE FLAVOUR SIMULATION IN BUTTEROIL(ICAR-NDRI, KARNAL, 2022) POHARKAR PIYUSH SANTOSH; Writdhama PrasadGhee, a form of heat clarified butterfat, is one among the important indigenous dairy products consumed in India. About 30 % of the total milk produced in India is converted into ghee by different methods viz., indigenous (desi), direct cream, creamery butter and pre stratification method. Although, the pre-stratification method requires lesser energy during ghee boiling as compared to other methods but still a lot of energy is required in heating the contents to develop the characteristic ‘ghee’ flavour. Butteroil is another fat rich dairy product containing fat level similar to that of ghee, but it lacks severely in terms of flavor profile. Lack of flavor is due to the absence of the ‘ghee boiling step’ during its preparation. This also makes butteroil preparation an economic process because of the fact that moisture evaporation is performed under subatmospheric conditions. In view of these facts, the present study was undertaken to simulate ‘ghee flavor’ in butteroil. For this, butteroil was mixed with reconstituted concentrated skim milk (RCSM) in different ratios of 1, 1.5 and 2: 1 ratio, heat treatment was varied from 110-130 oC for 10 to 30 minutes and final mixing ratio was varied from 0.2 to 0.8:1:0 of heated to fresh butteroil. It was observed that the product obtained by an initial mixing ratio of 1:1, heat treatment of 120 oC for 20 minutes and final mixing ratio of 0.8:1 yielded most acceptable product. The optimized product was compared with ghee prepared using pre-stratification method and butteroil for quality attributes and storage stability. It was observed that the optimized product and ghee had similar flavor profile, fatty acid profile, FTIR spectroscopy and rheological attribute. Storage study was conducted in two packaging material viz. glass bottle and PE pouch for 4 months at 37±1 °C. It was observed that sensory scores decreased during the storage period along with an increase in the free fatty acids content and TBA value. Antioxidant activity was higher in case of optimized product as compared to control and it decreased significantly (p<0.05) during the storage period in both the packaging materials for all the samples. No significant difference (p>0.05) was observed for the changes in instrumental color values of the samples during storage in both the packaging materials. Extent of changes was higher in samples packaged in PE pouches as compared to glass bottles. Energy calculation during the ‘ghee boiling’ step revealed that ghee flavor simulation using burtteroil was an economic process as compared to ghee preparation using pre-stratification method.ThesisItem Open Access HEAT INDUCED AND SALT MEDIATED INTERACTION BETWEEN MILK AND SORGHUM PROTEINS(ICAR-NDRI, KARNAL, 2022) SOLANKI ASHISH ARJANBHAI; Yogesh KhetraThe global protein market is witnessing a significant increase owing to the growing consumer demands for healthy and nutritious foods. Present protein demand has been largely met by animal proteins particularly milk proteins. Good quality cost-effective composite foods have been developed in the past by combining milk and cereals together. In the present study, the interaction between sorghum (Sorghum bicolor) and milk proteins was explored. Despite being fifth most important cereal crop, sorghum is underutilized. In this context, manufacturing of sorghum and milk proteins composites can be of a great significance to address the increasing protein demands of consumers in a cost-effective manner. Sorghum and milk proteins were interacted together through application of heat and salt. A method for preparation of sorghum protein isolate (SPI) yielded 81.11% protein (w/w) from sorghum flour. Proximate composition, physico-chemical properties and techno-functional attributes of sorghum flour and SPI were determined. To determine the interaction between SPI and milk proteins, a SPI-skim milk composite protein matrix was prepared in such a way that each of the components i.e. SPI and skim milk supplied half of the total protein content. Skim milk alone was used as control. All samples were then heated at four different temperatures viz. 30⁰C (control), 70⁰C, 80⁰C and 90⁰C for thirty minutes each to induce protein-protein interactions. While for salt induced interaction, sodium bisulphite salt was added in samples at four different concentrations i.e. 1%, 2%, 3% and 4%. These salt added samples were kept at 30⁰C for 30 minutes, which allowed time to salt for its action. The pH of skim milk-SPI composite was lower than skim milk. Particle size showed that at each treatment, size of composite protein matrix was higher than skim milk protein. Zeta potential also indicated some signs of interaction. While flow curve displayed lower viscosity values for composite protein compared to milk protein at each level of treatment. Whereas, FTIR spectroscopy didn’t indicate any sign of interaction. Instrumental colour values also showed that L*, a* & b* values were lower in composite protein matrix compared to milk protein in case of heat and opposite trend was observed in salt induced interaction. SDS-PAGE analysis also revealed that interaction between proteins was increased as intensity of heat increased. Aggregation of protein molecules was higher in case of salt induced interaction compared to heat. The Heat treatment causes unfolding of proteins, thereby exposing the hydrophobic core, disulphide bonds and free sulfhydryl groups, which becomes accessible for bond formation via oxidation of free sulfhydryl groups or by rearrangement of existing disulphide bonds. While in case of salt, either electrostatic interactions or a balance between electrostatic force and hydrostatic interaction was responsible for association of proteins. More studies are required to investigate milk and sorghum protein interactions and the functionality of composite protein.ThesisItem Open Access FEASIBILITY STUDY ON THE DEVELOPMENT OF AN ON-PACKAGE FRESHNESS INDICATOR FOR BUFFALO MILK RICOTTA CHEESE(ICAR-NDRI, KARNAL, 2022) PATEL DHARMIK; Sangita GangulyRicotta is a soft, mild- flavored, unripened variety of whey cheese. Ricotta is a protein coprecipitate having high moisture content. Ricotta has a short shelf life due to its inherent quality like high moisture and low salt content. Attempts had been made previously to develop pHbased freshness indicator for Ricotta cheese which could not be successful. Therefore, present research work was undertaken to develop safe and ready to use chemo-responsive dye-based freshness indicator to monitor quality of buffalo milk Ricotta cheese. Initially, Ricotta cheese was stored in PET and glass jar at 5±1°C and changes in physico-chemical, sensory and microbial attributes were monitored. Moisture, water activity, pH sensory scores were significantly (p<0.05) decreased whereas acidity, TVB-N, standard plate count, yeast and mould count significantly (p<0.05) increased during storage of Ricotta cheese at 5±1°C. After 12 days, buffalo milk Ricotta cheese was unacceptable in terms of sensory and microbiological quality. No significant difference (p<0.05) was observed for physico-chemical, sensorial and microbiological changes of Ricotta cheese during storage packaged in two different packaging materials viz., PET and glass jar. To fabricate chemo-responsive dye-based freshness indicator for Ricotta cheese, preliminary trials were conducted using natural pigment (anthocyanin) based freshness indicator but colorimetric changes observed were statistically non-significant (p<0.05) for stored Ricotta samples. Subsequently, trials were conducted to standardize preparation protocols for ready to use freshness indicators using 3 different synthetic dyes. Based on the results obtained, suitable dye was selected for indicator fabrication. Suitable carrier materials were optimized to immobilize the selected dyes to form gel strips. During storage conditions i.e. 5±1°C, selected indicator labels (M1 and M2) were attached inside the storage containers of buffalo milk Ricotta cheese for their real time performance evaluation and estimation. It was found that the yellowness index of both indicator labels was positively correlated with color change, titratable acidity, standard plate count, yeast and mould and coliform count content while it was negatively correlated with the pH of Ricotta cheese. Regression equation was developed to estimate the relationship of indicator label response in terms of ΔE with suitable parameters. It can be concluded that the freshness indicator labels could be successfully developed for monitoring in-package quality of Ricotta cheese. Total volatile base nitrogen and ammonia may be considered as main responsible component for changing color of developed freshness indicator.ThesisItem Open Access Estimation of Shelf-life of Moringa oleifera Fortified Functional Processed Cheese Spread(ICAR-NDRI, KARNAL, 2022) ALOK AHALE; Neelam UpadhyayConsumer demand is slowly turning towards safe, functional, nutritious and complete food as health consciousness amongst en masse is rising. The eating habit of people is shifting towards cuisines that are not only fast to prepare but also nutritious. Fortification is one of the most effective tools for addressing the problem of nutritional deficiencies and thus contributing to India’s progress towards achieving UN Sustainable Development Goal (SDG) of ‘ending all forms of malnutrition by 2030'. One such attempt to enhance the functional properties of processed cheese spread was made by incorporating Moringa oleifera in the form of its pods. In the present investigation, scaled up production of functional processed cheese spread (FPCS) was carried out and its characterization was done in terms of proximate, physico-chemical, bio-functional, rheological, textural attributes, besides sensorial and microbial analysis. The developed product was found to possess significantly higher (P<0.05) antioxidative, bio-functional attributes and iron content in comparison to the control (CPCS), while all the physico- chemical attributes (with an exception to TBA and FFA content) showed non-significant difference (P>0.05) amongst the developed product and control. The developed functional product was packed in polypropylene containers, kept for storage at 5⁰C and analyzed for various physico-chemical attributes, bio-functional, rheological, textural, sensorial and microbial parameters at an interval of 15 days. The prepared functional processed cheese spread had significantly (P<0.05) higher antioxidant activity and bio-functional attributes throughout storage period. This also was evident from lesser lipolytic (TBA, FFA), proteolytic (Tyrosine value and ICC), and microbiological (SPC, Yeast and Mold, coliform count) degradation of FPCS over CPCS. However, both these attributes decreased throughout the storage for control and developed product. Further, during storage, no significant (p<0.05) changes were observed in colour values of the product. Rheological parameters were also determined for changes throughout the storage and in both CPCS and FPCS, G' and G" increased throughout the storage indicating the dominance of solid behavior over viscous. FPCS had microbial counts under the safety limits prescribed by FSSR (2021) till 157th day of storage, while for CPCS it was till 135th day indicating improved antimicrobial properties of FPCS. The functional processed cheese spread was found to be the best when consumed till 5 months after packaging, while control product showed a shelf life of 4 months. The cost and consumer acceptability of the functional processed cheese spread was carried out. The cost of FPCS was found to be Rs. 296.65 per 500g compared to Rs. 233.93 for CPCS with 26.81% cost increase. The functional processed cheese spread was served to 87 people belonging to different age groups, gender, region for consumer acceptability and it was interesting to observe that 24% rated FPCS as excellent, while 49% of consumers found product to be very good, and 27% rated the product as good.ThesisItem Open Access PROCESS STANDARDIZATION OF SWEET CREAM BUTTERMILK ADMIXED GHEE RESIDUE POWDER FOR CONVENIENCE FOODS: BURFI AND GULABJAMUN(ICAR-NDRI, KARNAL, 2022) ADITTYA DUTTA; Ganga Sahay MeenaGhee-residue (GR) is still considered as a dairy waste, while sweet cream buttermilk (SCBM) is mainly used in the production of skim milk powder. This study aimed to manufacture simulated khoa powder (SKP) using SCBM and ghee residue. Developed SKP was characterized for various powder parameters and also explored to formulate burfi and gulab jamun. After pulverization, fresh GR was admixed with fresh pasteurized SCBM and standardized to fat to total solids (TS) ratio of 0.30 using cream. Due to the lower pH of GR, their mixture got coagulated at 50±1⁰C. This problem was overcome with the addition of selected levels of stabilizing salts. Dispersions of GR, PSCBM and stabilizing salts without and with shear treatment were referred to as unstable dispersion (USD) and stable dispersions (SD), respectively and characterized for their chemical composition, thermal stability and rheological parameters. Thereafter, SD samples were converted into SKP through spray drying. The prepared SKP had 98.68-99.39% TS, 29.06-34.91% fat, 31.52-41.80% protein, 4.68-5.29% ash, and 22.71-28.45% lactose contents. The occluded and interstitial air contents, loose and packed bulk densities, porosity, flowability, d50, HMF content, TBA & peroxide value and free fat content of these powders significantly (p<0.01) differed with each other. Their flowability was better compared to khoa powder, while wettability was comparable to whole milk powder. FRAP and DPPH of SKP samples were statistically at par (p>0.05). SKP samples were also characterized by FTIR, XRD, GC analysis and SDS-PAGE. SEM micrograph revealed the presence of variable particle size, clustering and particle infusion responsible for poor dispersibility and solubility. The overall acceptability of SKP samples varied between ‘liked moderately’ to ‘liked very much’, but the overall acceptability of burfi samples made from them varied from ‘liked slightly’ to ‘liked moderately’ on a 9-point hedonic scale. SEM micrograph revealed close-knit texture and compact body in burfi samples. The use of SKP in the preparation of gulabjamun was not feasible due to crust formation that hindered the penetration of sugar syrup inside gulabjamun samples.ThesisItem Open Access SPRAY DRYING OF DOUBLE-EMULSION-ENCAPSULATED DIPEPTIDYL PEPTIDASE-IV (DPP-IV) INHIBITORY PEPTIDES FROM Κ-CASEIN(ICAR-NDRI, KARNAL, 2022) RATHOD NILESHKUMAR HARISINH; LATHA, SABIKHIDiabetes is a metabolic disorder characterized by increase in blood glucose level resulting from lower insulin secretion or action. One way of controlling type 2 diabetes is inhibition of the enzyme DPP-IV. Many food or milk-derived peptides, including those from κ-casein, naturally exhibit DPP-IV inhibitory activity. Bioactive peptides are sensitive to the surrounding environmental stresses like pH, temperature and GI transit conditions. These can be overcome by their encapsulation by several means such as double emulsion. Spray drying of double emulsion with suitable filler matrix can improve stability of encapsulates and increase product specific application. Based on these aspects, the current study was carried out for spray drying of double emulsion containing DPP-IV inhibitory peptides. Gum arabic (GA), maltodextrin (MD) and β-cyclodextrin (β-Cd) were selected as materials for carrier matrices and used in seven combinations. Average protein content (%), oil content (%) and ash content (%) of powders were 1.0342±0.12%, 34.12±0.86% and 5.76±0.14%, respectively. Powder containing β-Cd-30% showed highest encapsulation efficiency of peptides (89.32±1.91%), while the GA-30% containing powder had the highest encapsulation efficiency (EE) of oil, solubility, dispersibility and wettability, of 65.1±2.47%, 82.17±0.81%, 48.08±0.80% and 4.42±0.5 s, respectively. According to Carr index and Hausner ratio, all powders possessed poor to very poor flow properties. The optimized double emulsion powder was selected on the basis of hygroscopicity, dispersibility, wettability, solubility, EE of peptides/proteins and EE of oil, which were assigned appropriate weightages. The powder containing 30% gum arabic in carrier matrix solution was found the best among the seven on the basis of the weighted scores. This optimised powder (GA-30%) was stored for 60 days at 30 °C and analysed for changes in physicochemical and functional properties at 15 days intervals. During storage, moisture content, water activity, particle size, bulk density, tapped density, particle density and peroxide value increased significantly. Storage affected functional, flow, reconstitution and microbial properties negatively and significantly. Hygroscopicity, bulk porosity, EE of peptides and EE of oil decreased significantly. κ-casein hydrolysates from milk of Gir cows showed IC50 value of 84.70 μg of protein per ml of solution for DPP-IV enzyme inhibition. The optimised double emulsion and spray dried double emulsion showed maximum respective DPP-IV inhibition of 79.92±0.81% and 71.99±1.62% in intestinal phase of simulated in vitro gastro-intestinal digestion. Stage of digestion and samples had significant effect on controlled release of peptides. On the basis of the present investigation, it can be inferred that the matrix material had significant effect on powder properties and that spray drying is suitable for drying of double emulsion with peptides. Stability of double emulsion was acceptable after spray drying and the peptides were still functional after the drying process.
