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ThesisItem Open Access STUDIES ON THE DEVELOPMENT OF AN ON-PACKAGE COLORIMETRIC FRESHNESS INDICATOR FOR SANDESH(ICAR-NDRI, KARNAL, 2020) KARPURAPU UMA; P. NARENDER RAJUThe present investigation was taken up to develop freshness indicator for sandesh, a milkbased confection. The developed freshness indicator is based on headspace volatile organic compounds liberated during storage. Samples were stored in three types of packaging materials namely clear (CG) and dark/amber colored glass containers (DG) and polystyrene trays (PS) at 6°C, 30°C and 45°C. Biochemical, microbial, sensory changes and concentration of head-space volatiles in sandesh were determined at definite intervals. Headspace solid phase micro-extraction coupled with gas chromatography mass spectrometry (HS-SPME-GCMS) was used for extraction and identification of volatile compounds from the package headspace. During storage a series of volatile organic compounds (VOCs) belonging to different chemical classes such as alcohols, ketones, aldehydes, acids, alkanes, alkenes, amines, amides, esters and ethers and other miscellaneous compounds were generated and their dynamics were monitored. Among these classes, acids, alcohols, alkanes, ketones and aldehydes especially 2-ethyl 1-hexanol; 2-propyl-1-pentanol; ethanol; methanol; pentane, 2,2,3,4-tetramethyl-; decane; ethane; acetone; 2- pentanone; 2-heptanone and acetaldehyde were found to be predominant in the product at the end of the shelf life. Correlation analysis revealed that volatile compound changes were well correlated with quality changes in sandesh. Based on the statistical analysis, the key VOCs responsible for the spoilage were selected and used for the fabrication of freshness indicator. Nine metalloporphyrins were selected and impregnated on cellulose based supporting material. However, they were not found suitable. Further, five different dye-based formulations were prepared and corresponding freshness indicator labels were developed (L-1, L-2, L-3, L-1A and L-1B). Labels were exposed to acetone, 2-pentanone, 2-heptanone, 2-nonanone, acetaldehyde, butanal, hexanal and nonanal. Among all, label L1B was selected based on sensitivity and reactivity with the selected volatile compounds. Selected indicator was mounted on the lids of the packages of freshly prepared samples and stored at 6°C, 30°C and 45°C. The changes in the color values were monitored in terms of total color change (ΔE). At 30°C and 45°C, color values were found to be highly significantly correlated with quality changes. Hence, the study demonstrated successful development of intelligent freshness indicator for packaged sandesh stored at 30°C and 45°C.ThesisItem Open Access EVALUATION OF DIPEPTIDYL PEPTIDASE–IV INHIBITORY POTENTIAL OF HYDROLYSATES OF β- AND k-CASEINS ISOLATED FROM Gir COW MILK(ICAR-SRS-NDRI, KARNAL, 2022) Harshita Sonarthi; SATHISH KUMAR M. H.The present study aimed at production of dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides from beta and kappa caseins from Gir cow milk. The hydrolysis of isolated caseins was done using different proteolytic enzymes viz., Flavourzyme (50˚C, pH 7), pepsin (37˚C, pH 2), proteinase K (37˚C, pH 7.5), and trypsin (37˚C, pH 8) at different enzyme substrate ratio (1, 2 and 4%) for 2 to 12 h duration. Aliquot samples were collected at every 2 h intervals. The degree of hydrolysis (% DH) varied significantly (p<0.05) with the enzymes used and was in the order of proteinase K > Flavourzyme > pepsin > trypsin using beta casein substrate. In case of kappa casein, the degree of hydrolysis decreased in the order of Flavourzyme > proteinase K > pepsin > trypsin. The kappa casein showed maximum DPP-IV inhibition (83.80 ± 0.68 %, IC50= 0.061 mg/mL) with trypsin enzyme at 4% E:S ratio and 12 h hydrolysis duration. While beta casein showed maximum DPP-IV inhibition of 50.41 ± 1.44% (IC50=4.39 mg/mL) at 4% E:S ratio and 10 h duration with Flavourzyme enzyme. The hydrolysates that showed maximum DPP-IV inhibition were fractionated through ultrafiltration membrane (10 and 3 kDa) and subjected to preparative RP-HPLC to collect time based fractions. All fractions were analyzed for DPP-IV inhibitory potential. Fractions which showed maximum DPP-IV inhibition were subjected to LC-MS/MS for amino acid sequencing. The data from MS/MS were processed using search engine PEAKS for peak picking and further search with data base ‘bovine_milk_2020’ from UNIPROT database to confirm the amino acid sequence of peptide. Peptides which have less number of amino acids were selected for synthesis from unique peptides of specific caseins and evaluated for their DPP-IV inhibition activity. Novel peptides with adequate DPP-IV inhibition activity were identified from both beta and kappa caseins which were not reported earlier. Beta casein permeate of 3 kDa exhibited significantly (p<0.05) higher DPP-IV inhibition compared to kappa casein counterpart. Hence, less than 3kDa permeate of beta casein was selected for evaluating efficacy in the cell line model. MIN6 cells were grown in DMEM at 37˚C and 5% CO2. DPP-IV inhibition activity and dose dependent glucose induced insulin secretion were assessed with different hydrolysate concentrations viz., 0, 10, 20 and 30 mg/mL and later concentration was able to produce significantly (p<0.05) higher amount of insulin and hence, selected for further evaluation. Further, significant reduction (p<0.05) in apoptosis was observed when cells were treated with 30 mg/mL hydrolysate. Consequently, pro-apoptotic genes viz., CASP-3, BAK, BAX were down regulated while MCL1 (anti-apoptotic gene) was up-regulated when cells were treated with 30 mg/mL hydrolysate. Hence, it confirms the insulinotropic action of prepared hydrolysate through DPP-IV inhibition.ThesisItem Open Access DEVELOPMENT OF RICOTTA CHEESE WITH EXTENDED SHELF LIFE FROM COW MILK SYSTEM(ICAR-NDRI, KARNAL, 2022) SHELKE PRASHANT ASHOK; LATHA SABIKHIWhey is co-product of cheese industry. More than 200 MT of whey is generated per annum. About 50% whey is processed to manufacture various value-added dairy products, while the remaining is drained, leading to loss of valuable nutrients and environmental pollution. The share of cow milk cheese whey is more than 80% of total whey generated. Ricotta cheese manufactured from cow milk whey is inferior to those from goat or sheep milk cheese whey. Shelf life of fresh Ricotta cheese is very low and has been extended using hot packing or adding chemical preservatives. These have negative effects on the sensory quality of cheese and heath of consumers. The present study was undertaken to utilize cow milk cheese whey to develop improved quality Ricotta cheese and extend its shelf life using natural antimicrobial agents. During this investigation the effect of varying levels of cheese whey to skim milk ratio (70:30, 80:20, 90:10), heat treatments (95, 90 and 85℃ holding for 10, 20 and 30 min each) and coagulation on properties of Ricotta cheese were evaluated. The developed Ricotta cheese was evaluated for storage stability and enhancement of shelf life using MicroGARDTM 100 (0.25, 0.5 and 1.0%) and Nisaplin® (100, 250 and 500 mg/kg). The composition, yield, solids recoveries, colour, spreadability, sensory, viscoelastic and flow behaviour properties were significantly influenced by levels of cheese whey to skim milk ratio, heat treatment, whereas coagulation temperature had no significant effect, except on sensory properties. The composition and solids recoveries increased with increasing proportion of skim milk in the blend and severity of heat treatment, but higher levels of skim milk had adverse effect on colour, spreadability and sensorial acceptability. The 90:10 cheese whey to skim milk blend and higher heating temperature (95℃) resulted in Ricotta with high moisture, fat, protein recovery, colour, spreadability and sensory acceptability, as also corroborated by principal component analysis (PCA). Higher cheese whey to skim milk ratio, heating temperature from 85 to 90 ºC and holding for 10 min led to the formation of a packed, denser and homogeneous network of protein, which further resulted in increased elasticity, viscosity, yield stress and decreased flow index and tan δ of cheese matrix. Heating temperature of 95 ºC and holding times of 20 and 30 min resulted in an increased number of small pores and hydration, which loosened the protein network and caused decreased compactness, elasticity, viscosity, and yield stress and increased flow index and tan δ. The rheological properties were influenced by microstructural features and can be manipulated by altering WP:casein of system and applying appropriate heat treatment. Descriptive sensory properties (except salty, adhesiveness, curdiness, firmness and granularity) and overall acceptability were highest in cheeses made from coagulation at 65℃. It is possible to produce whiter, uniform, easily spreadable, shiny, soft, creamy, granular, adhesive, highly acceptable and higher structural strength Ricotta from 90:10 cheese whey to skim milk ratio, heat-treating at 95 ℃/10 min and coagulating at 65℃. The developed Ricotta cheese had nearly similar characteristics of market samples and contained, respectively, 20.06, 11.89, 3.28, 1.35, 3.55, 9.15 and 90.55% of total solids, protein, fat, ash, lactose, yield and protein recovery. Whey proteins comprised more than 50% of the total proteins. Heat treatment at 95°C /10 min led to interaction and precipitation of ~ 100% of α-lactalbumin and 95.92% of β-lactoglobulin with casein micelle after acid coagulation. The product was sensorially and microbiologically acceptable up to 12th day of storage in glass jar and PET containers. Shelf life of Ricotta cheese increased by 8 days (66.66%) by the addition of MicroGARDTM 100 @ 1%, which was able to inhibit SPC, Enterobacteriae and yeasts and molds by 2.05, 2.07 and 1.51 log CFU, respectively. The production cost of Ricotta cheese was Rs. 189.77/kg. The study concluded that use of higher proportion of cheese whey in the whey-skim milk blend favours maximum utilization of Cheddar whey in the production of Ricotta with desirable quality attributes. These processing interventions could be a promising alternative to recover milk solids from whey and improve structural rheological and textural properties of cow milk Ricotta cheese.ThesisItem Open Access DEVELOPMENT OF GOAT MILK BASED PROBIOTIC YOGHURT(ICAR-NDRI, KARNAL, 2022) M DHARANI KUMAR; ASHISH KUMAR SINGHRichness of bioactive components and excellent nutritional make-up of goat milk has attracted the attention of stakeholders. Goat milk based ethnic dairy products are prepared and consumed in middle-east, southern Europe and Latin American countries, however no such product is available in Indian market. Lower total solids level, lack of α-S1 casein and predominant goaty flavour influence the textural and sensory acceptability of goat milk based fermented milks. The present investigation was carried out with the aim of developing set type probiotic yoghurt from goat milk employing different technological interventions. L. rhamnosus RSI-3 was selected as a suitable starter for the preparation of probiotic goat milk based yoghurt among four probiotic strains (L. rhamnosus RSI-3, L. rhamnosus LGG, L. fermentum RSI2 and L. acidophilus). S. thermophilus MC1 and S. thermophilus (NCDC 437) were selected co-cultures with probiotic strain. A split plot design consisting of three variables fat percentage, inoculum level and type of culture (EPS/non EPS S. thermophilus) was used to optimize the variables. Fat content was optimized to 3 % and 4% inoculum level (consisting of L. rhamnosus RSI 3 and S. thermophilus MC1). Supplementation of MPC 60 & MPC 80 into goat milk positively supported the growth of L. rhamnosus (RSI3) and S. thermophilus (MC1) in GMY samples. There was significant improvement in textural properties including firmness, work of shear, stickiness and work of adhesion with the level and type of milk protein concentrate (MPC60 and MPC80). Rheological analysis of goat milk yoghurt (GMY) samples revealed that elastic modulus (G′), viscous modulus (G″) and complex viscosity (η) increased while flow behaviour index (n) and phase angle (tan δ) decreased by enhancing the milk protein concentration levels. Textural improvement was investigated by using a combination of ultrafiltration (UF) and high shear treatment (HSST) of goat milk and UF 3 X concentrations was rated best. Significantly (p < 0.05) higher firmness (2.91±0.19 N) value was observed for yoghurt made with UF 3X than UF 2X. UF and HSST treatments had significant (p < 0.05) differences in the lightness (L*), yellowness (b*) and chroma values. Increase in lightness (L*) values was observed with increase in speed of HSST irrespective of concentration. The maximum (49.37±0.76) and minimum (8.72±0.60) viscosity was exhibited for UF2X-15K and UF3X-18K yoghurt, respectively. With increase in degree of UF concentration there was increase in Lactobacillus and Streptococcus counts. Ultrafiltered goat milk was subjected to enzymatic cross linking using 3 levels (1, 3 and 5g/L) of microbial transglutaminase (mTGase) at two different pre-incubation temperatures (40°C and 50°C). All textural properties of GMY significantly (p<0.01) improved by both increasing level of mTGase and pre-incubation temperature except for work of adhesion and stickiness which were not significant at pre-incubation temperature (p>0.05). Prebiotics supplementation at different levels (0%, 2% & 4%) significantly (p < 0.01) influenced the all textural parameters of yoghurts, while type of prebiotic substance (i.e Inulin, oligofructose and oat flour) had significant (p<0.05) effect on firmness and stickiness of yoghurt . The optimized product had 23.26%, 9.08%, 3.01% and 34.83 Pa.s total solids, protein, fat and apparent viscosity, respectively. The GMY proved to be an effective probiotic carrier matrix for L. rhamnosus RSI3 during simulated GI transit, with final count over 7.77 log CFU/mL. Storage stability using four different packaging materials (glass, High impact polystyrene-HIPS, High density polyethylene- HDPE and Polypropylene- PP) at refrigeration temperature was carried out. Increase in titratable acidity, proteolysis, TBA value, storage modulus, loss modulus and complex viscosity values were observed irrespective of packaging materials. Decrease in pH, probiotic count, S. thermophilus count and sensory scores were observed in all the packaging materials. However probiotic count in all packaging materials was more than 7.5 log cfu/mL on 21st day of storage. Glass bottles were found as better packaging material followed by HIPS cups in terms of significantly higher probiotic counts and sensory properties. The developed product analysed for health beneficial attributes in pathogenic E. coli challenged Swiss albino mice model and GMY feeding improved the immunomodulatory and antioxidative status. Cost of production per 200 gm product packed in HIPS cups was estimated to be around Rs. 27.25.ThesisItem Open Access DEVELOPMENT OF TECHNOLOGY FOR REDUCEDCALORIE BASUNDI(ICAR-NDRI, KARNAL, 2020) MAYANK SINGH; KAUSHIK KHAMRUIIn India, about half of the milk produced annually is converted into Traditional Indian Dairy Products. They are highly valued in society as a gustatory enjoyment as well as a source of nutrition. A study was undertaken to optimize the production process for manufacturing reduced-calorie basundi and enhance its shelf life. The levels of sucralose, maltodextrin, sorbitol, and inulin was optimized using full factorial design. Based on sensorial, rheological and colour attributes, the combination having maximum desirability of (0.851) was selected as optimized basundi. The optimized solution was 65 ppm sucralose, 5% maltodextrin and sorbitol mix (1:1) and 1.5% inulin. The predicted scores for flavour, colour and appearance, consistency and overall acceptability were 7.70, 7.69, 7.54 and 7.64, respectively. There were non-significant differences between actual and predicted scores. The optimized product contained 65.30±0.01 of moisture, 1.11±0.01% fat, 8.49±0.32% protein, 9.22±0.61% lactose, 10.90±0.12% other carbohydrates (due to maltodextrin), 142.12 ppm sucralose and 1.49±0.18% ash. The flow curve for optimized and control basundi had shown the pseudoplastic nature as viscosity was decreased with an increase in shear rate. The apparent viscosity for control and the optimized basundi was 14.3±1.30 and 32.3±2.10 mPa.s, respectively. The Herschel-Bulkley was found the best-fitted model based upon the coefficient of correlation (R2) value 0.999. SEM had shown that the optimized basundi was having the network or web-like structure while in control basundi constituents were seen embedded in fat phase. The effect of potassium sorbate was evaluated on the shelf life of basundi by monitoring changes in sensorial, microbial and chemical quality of the product, packed in polypropylene (PP) and polystyrene (PS) containers at 30±1ºC and 5±1ºC. All the sensorial attributes of reduced-calorie and control basundi with or without preservative reduced significantly (p<0.05) throughout the storage period at both the temperature. Both potassium sorbate (0.1%) added basundi and control basundi deteriorated within 3 days at 30±1ºC in both the packaging material. At refrigerated temperature (5±1ºC) potassium sorbate (0.1% of final product) containing reduced-calorie basundi was found to be acceptable for 19 days while control remained acceptable for 14 days only. The colour characteristics, i.e., lightness (L*), redness (a*) and pH, water activity of product decreased significantly (p<0.05) during storage while b* (yellowness) value, titrable acidity, free fatty acid, hydroxymethylfurfural increased significantly (p>0.05) when packed and stored in both the packaging materials and temperatures. The extent of chemical change was more at 30±1ºC. The retort processing performed at 115±1ºC for 5 minutes in sterilizable polypropylene (PP) containers increased the shelf life of reduced-calorie basundi up to 30 days. The di-sodium phosphate as a stabilizer was added at 0.012% of the finished product. The HPTLC revealed that no degradation occurred of sucralose after retort processing when stored at 30±1ºC for 30 days in PP containers. The reduced-calorie basundi contained 31.04% less energy (calorie) as compared to full fat and sugar-containing counterpart. The production cost of retorted reduced-calorie, reducedcalorie and control basundi in PP containers were estimated as ₹ 138.25, 137.94 and 91.78 per kg, respectively.ThesisItem Open Access STUDIES ON OPTIMIZATION OF BUTTERMILK BASED DRIED FLAXSEED OIL ENCAPSULATE(ICAR-NDRI, KARNAL, 2020) KUMAR, RAJENDER; SABIKHI, LATHAOmega-3(ɷ-3) fatty acids have attracted enormous interest due to the health concerns related to saturated fats and low ɷ-3/ɷ-6 ratio. Due to the susceptibility of these PUFAs to oxidation, shelf-life of ɷ-3 oils is limited. The current project was aimed to develop a suitable ɷ-3 delivery system by loading the maximum amount of ɷ-3 rich oil in buttermilk with minimum oxidation of the oil. Buttermilk as well as buttermilk concentrate were used for the preparation of emulsions of ω-3 oil. Pre-emulsions of buttermilk-flaxseed oil (2, 3 and 4% oil) and buttermilk concentrate-flaxseed oil (6, 9 and 12% oil) were prepared using a high speed homogeniser operating at 12,000 rpm for 5 min for mixing of oil in buttermilk. The optimised emulsion was physically stable for a period of 21 days with an average particle size and zeta potential of 401.7±43.6 nm and -22.3±0.21 mV, respectively. Buttermilk concentrate based emulsion was selected for drying, as it exhibited significantly (P<0.05) lower oxidation than the buttermilkbased emulsion. Thermal stability of the emulsion was evaluated in the temperature range from 40°C to 80°C. The emulsion was stable for 5 and 10 minutes at 70°C and 80°C, respectively. Adequate to good encapsulation efficiency of the emulsion was confirmed by confocal laser scanning microscopy and light microscopy. Emulsion was stable for a period of 15 days at 5±1°C during which, the respective values of pH, peroxide value, p-anisidine value and TBA increased significantly (P<0.05) from 6.463±0.004 to 6.349±0.008, 2.30±0.06 to 2.89±0.07 meq peroxides/kg, 0.51±0.02 to 0.86±0.02 meq/kg and 0.10±0.01 to 0.21±0.01 mmol malonaldehyde/kg. Confocal laser scanning microscopic examination during the course of storage further confirmed the stability of the emulsion. Emulsion dried at 190oC inlet air temperature showed significantly (P<0.05) lower water activity and moisture content, based on which 190°C was selected as final inlet air drying temperature. Buttermilk milk concentrate flaxseed oil encapsulate was packed in LDPE, Met-PET and Met-BOPP and evaluated at an interval of one month for its storage stability at 25±1°C for a period of six months. The study indicated that buttermilk, by virtue of its phospholipids-rich fragment i.e. milk fat globule membrane, can stabilise and prevent the oxidation of ɷ-3 rich oil. Buttermilk can serve as a matrix for the encapsulation of ɷ-3 rich oil, which will not only solve the problem of disposing the buttermilk in dairy industry, but also classify it as a vehicle for the functional ingredient ɷ- 3 oil.ThesisItem Open Access ASSESSMENT OF FUNCTIONAL PROPERTIES IN CHEDDAR CHEESE MADE FROM THE MILK OF DEONI AND CROSSBRED COWS USING HYDROLYSED CHEESE SLURRY(ICAR-NDRI, KARNAL, 2021) SOUMYASHREE T C; BIKASH C. GHOSHThe aim of present study was to assess the functional properties between the Cheddar cheese made from the milk of Deoni (DMCC) and Crossbred cows (CMCC). Deoni milk had total solids content of 14.12 % and contents of protein, fat, lactose and ash were 3.28, 5.2, 4.64 and 0.75, respectively. The DMCC and CMCC were prepared and analysed for proximate composition and bio- functional properties. Soluble protein content of DMCC was significantly higher (P<0.05) than CMCC at the end of 12M. The Free fatty acid content (meq KOH/100g of fat) of CMCC increased significantly (p<0.05) than that in DMCC throughout the ripening. The pH of the cheeses decreased upto 2nd month of ripening, afterwards it increased throughout ripening for both the cheeses. The total bacterial count in DMCC showed a significantly (p<0.05) higher count than the CMCC after fourth month of maturation. The degradation of protein was more in DMCC compared to CMCC throughout the ripening, which was revealed by Urea-PAGE and confirmed by RP-HPLC. The overall acceptability score of DMCC was appreciably higher (P<0.05) compared to CMCC. DMCC had optimum pleasant flavour with close, smooth and shiny appearance. Water soluble extract (WSE) of DMCC showed higher (p<0.05) ACE inhibition and higher (p<0.05) % DPPH scavenging activities than the extracts of CMCC during ripening. WSE of DMCC had significantly (p<0.05) higher per cent inhibition of DPP-IV than CMCC at 12th month of ripening. Cheddar cheese was made with addition of hydrolysed cheese slurry to accelerate maturation and improve the bio-functional attributes. Hydrolysed cheese slurry was incorporated at 5 and 10% in Cheddar cheese to assess the ripening characteristics for 6 months. During maturation, the presence of hydrolysed cheese slurry in Cheddar cheese curd showed a significant effect (p<0.05) on FFA and soluble protein formation in cheese. UREA-PAGE and RP-HPLC chromatograms have confirmed greater proteolysis in slurry containing cheeses revealing clear differences in the peptide profile compared to control. The total bacterial count in all cheeses decreased significantly (p<0.05) after the 2nd month of maturation. Cheese made from Deoni milk with 5% hydrolysed slurry was superior and was distinguished by a smooth texture than the control cheese and cheese with 10% hydrolysed cheese slurry. Water soluble extract (WSE) of Cheese with hydrolysed cheese slurry exhibited higher (p<0.05) antioxidant, ACE and DPP-IV enzyme inhibitory activities than cheese made without hydrolysed slurry. The maturation time was improved by 19.43% and 28.33% for 5 and 10% hydrolysed slurry added cheeses respectively for soluble protein and 42.21% and 65.37% for 5 and 10% hydrolysed slurry added cheeses respectively for FFA.ThesisItem Open Access TECHNOLOGY OF GLUTEN FREE MULTIGRAIN VERMICELLI KHEER AND ITS INSTANT MIX(ICAR-NDRI, KARNAL, 2021) ASHU; KAUSHIK KHAMRUIThe present investigation was carried out with the aim of developing gluten free multigrain vermicelli (GFMV) kheer and its instant mix using vermicelli prepared from combination of amaranth, rice, green gram and cassava flour. Hydrothermal treatment of amaranth, rice and green gram grains by subjecting them six minutes of steaming was found to be optimum based on maximization of peak, trough, breakdown, final and setback viscosity of flours. Response surface methodology was used to optimize the level of ingredients for vermicelli preparation and the combination with 60.5% of amaranth flour, 22% of rice flour, 13.5% of cassava flour and 4% of green gram flour yielded highest desirability (0.859) hence selected as optimized combination. Further treatment of the dough with Carboxyl esterase enzyme @ 1.5% resulted in a fibrous structure with few visible starch granules deeply embedded in the protein matrix. The entire dough surface appeared to be coated with smooth protein film with lowest cooking loss (0.2%) and maximum sensorial attributes. Steaming of wet vermicelli strands before drying for 15 minutes, exhibited good integrity, improved rate and completeness of hydration, lower cooking loss. Drying temperature of 80o C/2 hr resulted in proper removal of moisture from vermicelli while retaining its shape and integrity. Scanning electron microscopy study effectively described the changes in protein and starch interaction in dough due to the combined action of hydrothermal and enzymatic treatment. Addition of 0.30% of xanthan gum helped to enhance the instant attributes of the vermicelli by improving the water holding capacity (293%), swelling index (4.59%), cooking weight (98.73g) and minimizing cooking time to 7 minutes and cooking loss to 0.4%. The technology for instant GFMV kheer mix powder was developed by spray drying (inlet air and out let air temperatures 175±5° and 80±3°C, respectively) of mixture of concentrated (35% TS) milk with 3% fat and 9% SNF added with 0.03% multigrain flour followed by drying blending of powdered sugar and BHA. Reconstituted GFMV kheer was standardized by solubilizing the spray dried powder with water ratio of 1:5, addition of vermicelli @ 10% of reconstituted milk and cooking for 7 minutes. Gluten free multigrain vermicelli contained high amount of protein (14.32%), fat (2.64%), iron (7.11 mg), calcium (120.81 mg), magnesium (180.72 mg) and zinc (1.49 mg/100g) which were found to be much higher as compared to commercially available wheat-based vermicelli. In-vitro protein digestibility of gluten free multigrain vermicelli was also found to be much higher (76.53%) than commercial wheat vermicelli (49.42%). Shelf life of instant kheer mix powder packed in paper laminated HDPE pouches was observed to be six months and when packed in metallized polyester LDPE pouches was seven months at 30oC. In consumer acceptance study, it was found that maximum number of consumers (36%) rated the developed product as “very good”, 32% as “excellent” and 24% consumers rated as “good” and 8% rated as “fair” degree of liking. About 89% of the consumers were willing to buy instant GFMV kheer mix due to its convenience and high nutritional value. Cost of production per kg of instant GFMV kheer mix packed in metallized polyester LDPE pouches was estimated to be Rs.295.ThesisItem Open Access TECHNOLOGY OF RIPENED CHEESE FROM CAMEL MILK(ICAR-NDRI, KARNAL, 2021) MOHAMMED DAVUDDIN BAIG; LATHA SABIKHICamel milk and its products are gaining attention worldwide, owing to their nutritional value. Though camel milk has excellent nutritious components, the technology of extending its shelf life by converting to its products (especially cheese) has been challenging. The current study aimed at preparing ripened cheese from camel milk, using rennet designated for camel milk and optimizing the process parameters. The optimised camel milk cheese was investigated for its ripening changes up to three months. The use of thermophilic culture (Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) added at S1, S2 and S3% to camel milk lowered pH from 6.65 to 6.23, 6.21 and 6.10, respectively, when ripened for 30 min. Increase in heat treatment to camel milk led to poor gel formation. The casein micellar diameter increased and storage modulus (G’) reduced with increasing intensity of heat treatment. Camel milk subjected to HT3 exhibited higher gel firmness compared to HT1, HT2 and HT4 samples. Calcium chloride added to camel milk (Ca1-Ca3%) resulted in higher gel firmness and lower rennet coagulation time (RCT) with increase in its level. Camel milk rennet (R1-R4 mg/L milk) used in this study led to lower RCT with increase in concentration. There was no significant difference in gel firmness between R3 and R4 mg/L rennet levels. Camel milk standardized to different casein to fat levels (CF1-CF3) had a significant positive proportional effect on solids recovery in cheese. The combined effect of cooking temperature (CT2), salting level (SL1) and pressing duration (PD2) on camel milk cheese curd resulted in lower moisture (51.7%) and higher cheese yield (9.28%) compared to other treatments. The storage modulus (G’) and loss modulus (G’’) also increased with increase in CT, SL and PD levels. During ripening, the moisture reduced significantly (p˂0.05) after 30th day, while there was no significant difference in fat, protein and ash content. The G’ and G’’ values of camel milk cheese decreased during ripening. Tan δ (G’’/G’) of cheese was less than 1 and significantly reduced with storage time ranging from 0.75-0.34. The hardness (N) of camel milk cheese decreased significantly from the 15th day till the end of ripening. The pH and water activity of camel milk cheese decreased respectively, from 5.98 and 0.974 to 5.18 and 0.962 by the end of ripening period. The titratable acidity increased and lactose was completely utilized by the microorganisms at 30th day of ripening. The water soluble nitrogen increased from 9.7 to 18.9% by the end of the ripening period. The total number of peptides released in camel milk cheese during ripening did not exhibit linearity in the HPLC chromatograph, though the concentration and peak areas increased progressively with ripening time. The free fatty acids increased from 0.09 to 0.30 mg/g fat at end of 90th day. The total SFA (%) and PUFA (%) remained consistent, while total MUFA (%) increased. The total plate count camel milk cheese increased significantly. There was no significant difference in S. thermophilus count, while L. bulgaricus increased till 45th day and then declined. The mean sensory scores of camel milk cheese indicated that it is high in salty taste, whiteness, curdy body and crumbly texture on day 1. All these parameters decreased gradually as ripening progressed, and bitterness set in. The cheese had small eye-like holes, attributed to the carbon dioxide produced by the starter bacteria. The yield, moisture, fat, protein and ash in the cheese were 9.28%, 52%, 19.80%, 24.70% and 5.40%, respectively. It was acceptable at the end of the 90 days study period. Camel milk cheese prepared during the current study could be classified as a semi-hard ripened cheese variety, with small eyes.
