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ThesisItem Open Access Screening of mango varieties for preparation of ready-to-serve beverage(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-08) Phool Chand; Chopra, C.S.The present study pertaining to evaluation of different cultivars of mango for preparation of ready-to-serve beverage (RTS) was conducted in the Department of Food Science & Technology, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S. Nagar (Uttarakhand) during the year 2008-09. The cultivars differed significantly in terms of fruit weight (110.0-574.5g), length (7.18-14.59 cm), breadth (5.23-9.07 cm), specific gravity (0.953-1.061) and content of flesh (58.18-79.90%), peels (9.10-22.52%) and stone (11.05-20.55%). Variations in pH (3.75-4.49) and content of TSS (11.5-17.33%), moisture (76.32-88.65%), acidity as citric acid (0.16-0.31%), vitamin C (15.30-107.27 mg/100g), ash (0.24-0.43%); reducing, non reducing and total sugars (3.08-4.64, 8.91-15.71 and 12.52-20.36%) in flesh were statistically significant, Fazli recorded highest fruit weight, length and breadth while these were minimum with Alphanso. Fazli having maximum flesh also had highest acidity while Pant Sindoori and Dashehari recorded minimum flesh and acidity, respectively. Langra flesh was found to be the richest source of vitamin C. Dashehari, Langra and Chausa varieties were selected for making RTS of composition 10% pulp, 10% TSS and 0.30% acidity, on the basis of their highest overall acceptability score (8.67, 7.89 and 7.33, respectively). The sulfited and in-bottle pasteurized drinks prepared from these selected cultivars had >6 months of shelf-life at ambient conditions.ThesisItem Open Access Effect of Aloe vera gel juice incorporation on the quality characteristics of yoghurt(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2006-07) Malhotra, Ruchika; Tyagi, S.M.Studies were conducted to investigate the effect of incorporation of aloe vera gel juice in milk on the quality characteristics of yoghurt. The level of aloe vera gel juice was optimized on the basis of growth and acivity in terms of pH and acidity. Yoghurt cultures L.bulgaricus and S. thermophilus and probiotic culture L.acidophilus were used singly or in combination to study the effect of varying levels of aloe vera gel juice added to cow milk containing 3.0% and 0.5% fat. A 10% aloe vera gel juice level gave desirable results, i.e. lowest pH and highest titratable acidity and total viable counts. Medium and low fat yoghurt samples were prepared from standardized milks containing 3.0% or 0.5% fat after adding 4 per cent Skim milk powder, 7 per cent sugar and 0.2-0.3% sodium alginate using C1 culture (L.bulgaricus and S.thermophilus,1:1,Control/Regular yoghurt), C2 culture (S.thermophilus and L.acidophilus ,1:1, Acidophilus yoghurt) and C3 culture (L.bulgaricus, S. thermophilus and L.acidophilus, 1:1:1, Bioyoghurt), with or without addition of optimized level of aloe vera gel juice. The moisture content of yoghurts ranged between 81.50 to 85.0% depending on the composition of milk and incorporation of aloe vera gel juice. The aloe vera added yoghurt had slightly lower fat, protein, carbohydrate and ash contents. Addition of aloe vera gel juice to yoghurt had a significant (P<0.01) effect on acid production. Lowest pH (4.30) and highest titratable acidity (1.0%) were obtained in medium fat yoghurt aloe vera added yoghurt with C3 culture followed by C1 and C2 cultures. The acetaldehyde, soluble nitrogen and free fatty acid contents significantly (P<0.01) increased on incorporation of aloe vera gel juice. The highest acetaldehyde (33.0 ppm) was produced in medium fat aloe vera added yoghurt prepared by C2 culture whereas maximum soluble nitrogen (0.078%) and free fatty acid (8.0 meq/ml) were given by C3 culture. The incorporation of aloe vera significantly (P<0.01) increased syneresis whereas decreased curd tension and viscosity. Maximum syneresis (22.3 ml) was observed in low fat aloe vera added yoghurt prepared using C1 culture while highest curd tension (45.5 g) and maximum viscosity (6200 cP) was obtained in medium fat yoghurt without aloe vera prepared by using C1 and C3 cultures, respectively. Total viable counts significantly (P<0.01) increased on adding aloe vera gel juice to yoghurt mix. The maximum total viable count (4.2 X108) was noted in aloe vera added medium fat yoghurt prepared by C3 culture. No yeast and mold counts were detected in fresh samples. During storage of yoghurt for 28 days at 5+10C, the lowest pH (3.10) and highest acidity (1.80%) was obtained in medium fat yoghurt without aloe vera prepared using C1 culture. The titratable acidity, soluble nitrogen, free fatty acid content, curd tension, syneresis and yeast and mold counts significantly (P<0.05) increased during storage whereas pH, acetaldehyde content, viscosity, total viable counts and sensory scores significantly (P<0.05) decreased during storage for all yoghurt samples. Yoghurts prepared from C1 and C3 cultures retained significantly (P<0.05) superior quality as compared to yoghurt prepared by using C2 culture. Keeping quality of aloe vera added yoghurts was better in all parametric terms than the ones without aloe vera. Satisfactorily good quality aloe vera gel juice added yoghurt with therapeutic value could be prepared by incorporation of 10 per cent aloe vera to medium fat as well as low fat milks with a shelf life of 24 days.ThesisItem Open Access Varietal suitability of mango for brining to produce pickle(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-08) Jasdeep Kaur; Chopra, C.S.The present study pertaining to evaluation of different varieties of mango for brine preservation to produce pickle was conducted in the Department of Food Science & Technology, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S. Nagar (Uttarakhand) during the year 2012-13.The variety Safeda Sharbati recorded highest fruit weight (178.47±30.66 g), length (7.73±0.45 cm) and breadth (6.62±0.42 cm) but flesh content (79.23±1.82%) was maximum in Bira. Acidity (as anhydrous citric acid) was also highest in Bira (2.16±0.13%). Fakira had highest level of vitamin C (35.79±0.85 mg/100g). Statistically, there were significant differences among the varieties with regard to physical and chemical characteristics. Fruit pieces produced from Bira, Croton, Fakira, Langare Mar, Malda Handle, Ramkela and Safeda Sharbati varieties of mango were kept at ambient temperature separately in brine solution containing 5% common salt, 1.2% acetic acid, 0.2% potassium metabisulphate and 0.5% calcium chloride for maximum eight months or until spoiled. There were varying level and kinds of changes in the brined pieces as well as in brine during storage. The levels of common salt and free sulphur dioxide in slices and brine were decreased due to storage however, total soluble solids and acidity exhibited inconsistent trends during the storage. Ascorbic acid was recorded maximum (35.79±0.85 mg/100g) in Fakira and minimum (13.24±1.47 mg/100g) in Malda Handle at the beginning of storage but it was reduced drastically in all the seven varieties to about 1-2 mg/100g at the end of eight months. Malda Handle was spoiled after four months of brine preservation. Bira, Croton and Ramkela were spoiled following six months of storage. Fakira, Langare Mar and Safeda Sharbati were however not spoiled upto eight months of ambient storage in brine. Pickle samples were prepared from these (Fakira, Langare Mar and Safeda Sharbati) brined mango pieces following eight months of storage and were well acceptable.ThesisItem Open Access Evaluation of suitability of different coagulants at various temperatures for making soy tofu(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2014-08) Saini, Deepa; Chopra, C.S.ThesisItem Open Access Technological refinement to preserve mango slices by dry salting(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2014-08) More, Anil Dilip; Chopra, C.S.ThesisItem Open Access Development of fibre enriched rusk(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-07) Manavi, B.S.; Chopra, C.S.The present investigation was carried out in the Department of Food Science and Technology, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S. Nagar (Uttarakhand) during the year 2013-15 with the objective to develop fibre enriched rusk through incorporating non-gluten flours in the existing recipe. Response Surface Methodology (RSM) was employed to optimize levels of oat, barley and finger millet flours along with refined wheat flour, sugar, skim milk powder and refined oil and processing conditions - baking temperature and time for making rusk. However, the amount of common salt (0.5 g), dry yeast (2.5 g) and water (50 g) was kept constant. Results indicated that use of 10.2 g oat flour, 10 g barley flour 10 g finger millet flour, 100 g refined wheat flour, 25.5 g sugar, 1.65 g skim milk powder and 13 g refined oil with baking temperature (170 ± 2°C) and time (20 ± 2 min) were found optimum for making ideal rusk. Loaf volume, specific loaf volume and organoleptic scores decreased with the enhancing levels of non-wheat flours incorporation and improved with the increasing levels of sugar and refined oil. Hardness of rusk increased with the increasing levels of barley flour and sugar while it was lowered with increasing the levels of oat and finger millet flours incorporation. Use of baking temperature and time beyond 170°C and 20 min affected the hardness and organoleptic profile of the rusk adversely. The rusk prepared by optimized recipe contained 6.6 times fibre content and 2.7 times calcium when compared with control. Moreover, RSM optimized rusk also recorded higher contents of crude fat, crude fibre, calcium and iron. Consumption of 100 g of fibre enriched rusk can fulfill 15.50 % of recommended daily requirement of calcium in the body. Such technology holds promise for being exploited at commercial level in the health food industry in future.ThesisItem Open Access Process optimization for chalta (Dillenia indica L.) juice extraction(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-07) Gandhi, Garima; Anil KumarFruit of chalta (Dillenia indica L.) having wide range of functional and neutraceuticals is distributed in Sub Himalayan tract and other parts of country but due to lack of awareness and technological advances gets wasted. Therefore, an attempt was made to derive a convenient and easy method for juice extraction from this fruit without compromising with its beneficial counterparts. The present investigation was undertaken to optimize process variables for four different kinds of pre-treatments (hot water, steaming, microwave and enzyme treatment) given to chalta fruit pieces in order to prepare juice/extract from the same. The levels of process variables were optimized by Central Composite Rotatable Design (CCRD) of Response Surface Methodology (RSM) and prepared extract was subjected to physico-chemical and sensory analysis. Results revealed that in case of microwave treatment, effect of heat treatment time was found highly significant (p<0.01) on acidity, Vitamin C, TSS, colour and aroma of the juice/extract at linear level and for TPC and IC50 at quadratic level and also found significant (p<0.05) for yield and consistency. Extraction time was found to influence acidity, reducing sugar, TPC and TSS of the extract significantly (p<0.05) at linear level and vitamin C and consistency at quadratic level. In steaming treatment, effect of heat treatment time was found highly significant (p<0.01) on acidity, reducing sugar, Vitamin C, TSS, colour, aroma and consistency at linear level and for TPC at quadratic level and it was also significant (p<0.05) for yield at linear level. Similarly, effect of extraction time was found significant (p<0.05) on acidity, reducing sugar and IC50 at linear and for TPC at quadratic level, respectively. It was also observed that in hot water treatment, soaking time affected colour and consistency significantly (p<0.01) at linear level and for vitamin C at quadratic level, whereas, TPC and IC50 were found significant (p<0.05) at both the levels. Extraction time was found to have significant (p<0.05) effect on IC50 and aroma at linear level and for acidity, vitamin C and TSS at quadratic level. Similarly, effect of temperature was found highly significant (p<0.01) on IC50, yield, TSS and consistency at linear level. Interactive effect of soaking time and extraction time on IC50 and heating time and temperature on Vitamin C were found highly significant (p<0.01) for extract from hot water treatment. In enzymatic treatment, results have shown that at linear level, effect of pectinase was found highly significant (p<0.01) on reducing sugar and TSS and significant (p<0.05) for aroma and IC50. Cellulase has also found to affect reducing sugar at linear level and acidity and yield at quadratic level significantly (p<0.01) whereas, incubation time showed highly significant (p<0.01) effect on acidity, vitamin C and consistency at linear level and TPC at quadratic level. TPC was also found to get affected significantly (p<0.01) at interactive level of cellulase and incubation time. Optimum levels obtained for microwave treatment were 4.72 minutes heat treatment and 15 minutes extraction time, while in steam treatment 5 minutes heat treatment time and 44.99 minutes extraction time. In case of dipping optimum levels were 2 hours heat treatment, 45 minutes of extraction and 90°C temperature whereas for enzymatic treatment 1% pectinase concentration , 0.98% cellulose concentration and 2 hour incubation time were obtained. Amongst the four pretreatments viz., hot water treatment, steaming, microwave and enzymatic treatment it was found that physico-chemical attributes including yield, TSS, Vitamin C, reducing sugar and acidity of chalta extract by using enzymatic extraction method while minimum for antioxidant activity (IC50 values) was minimum. Maximum sensory score of color and aroma was also obtained for enzymatic method as compared to other methods of extraction. Hence, enzymatic extraction method is considered best for preparing juice/extract from chalta fruit without adversely affecting the physico- chemical characteristics.