Thesis & Dissertations

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Browsing Thesis & Dissertations by TU Institute "Central Department of Food Technology"

Now showing 1 - 5 of 5
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    Effect of Cinnamomum Verum and Zanthoxylum armatum essential oil incorporated sodium alginate edible coating on the shelf life of Panner
    (Department of Food Technology, 2022) Pokhrel, Bimala
    The study was carried out with objective to evaluate the effect of Cinnamomum verum and Zanthoxylum armatum essential oil incorporated Na-alginate edible coating on shelf life of paneer. Paneer samples were prepared from cow milk using citric acid (1%) as coagulant and calcium chloride at different concentrations, 0, 0.05, 0.1, 0.15, 0.2 and 0.25% (w/v) of the milk and were evaluated for composition, sensory quality and yield. The best paneer was coated with sodium alginate edible coating incorporated with 2% of Zanthoxylum armatum and Cinnamomum verum essential oils and their mix at different combinations given by the D-optimal mixture design. The control (without coating) and coated paneer samples were packed in LDPE bags (48.7 g/m 2 and 50µm thickness), stored at 7±1ºC and 52% RH, and changes on sensory attributes, chemical composition and microbial load during storage were studied at 4 days interval till 24 days. Results showed that CaCl2 at different concentrations had significant effect (p<0.05) on composition, sensory quality and yield of the paneer but not on FFA. 0.1% CaCl2 added paneer was significantly different (p<0.05) than other samples and selected as best for further coating. Storage time and edible coatings had significant effect (p<0.05) on the sensory, physicochemical (acidity, FFA, tyrosine release) and microbiological characteristics of paneer. The overall sensory scores of uncoated and single essential oil coated samples were below 6 on the 8 th days and 16 th days respectively whereas Zanthoxylum armatum and Cinnamomum verum essential oil (1.75+0.25) % coated sample remained 7 till 24 days of storage. Among all the treated samples, Zanthoxylum armatum and Cinnamomum verum essential oil mix combination (1.75+0.25) at 2% of sodium alginate coated sample was significantly different (p<0.05) in chemical characteristis (moisture content, FFA, acidity, tyrosine released) and microbial characteristics (TPC and yeast mold count).
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    Improvement on Traditional Millet Fermentation Process and Its Brewing Quality Assessment
    (Faculty of Food Technology, 2013) Karki, Dhan Bahadur
    Available with full text
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    Optimization of vegetables proportion in emulsion type chicken sausage and study on its storage stability
    (Department of Food Technology, 2022) Bhattarai, Tanka
    This study was conducted with an objective of optimizing vegetables proportion in emulsion-type chicken sausage and evaluation of storage stability. The primary screening process was conducted in the first phase with various percentages (10, 20, 30 and 40) of vegetables (soybean, carrot and mushroom) on the basis of sensory evaluation and physicochemical properties of the prepared sausage. 30% formulation was selected from primary screening and 11 runs were generated from D-optimal mixture design. In second phase, the best percentage formulation was carried out on the basis of sensory evaluation and physicochemical properties which was then further analyzed for proximate composition, carotenoids content and antioxidant properties. The final phase of the study was carried out on storage stability of optimized sausage samples at -2°C in polyester based films (PET). Finally, optimized product was compared on the basis of sensory score with chicken sausage (control) available in Dharan sub-metropolitan. The optimized product from sensory analysis had a proximate composition, comparing 60.47, 11.89, 17.55, 0.43 and 4.17 moisture, crude fat, crude protein, crude fiber and total ash, respectively. The carotenoid content of the superior product was found to be 30 μg/ 100 g and DPPH radical scavenging activity of sausage was found to be 46.76%. There was a gradual increase in Total Plate Count (TPC) reaching maximum on day 18 (9 log/cfu) while Salmonella and coliform were not detected up to day 18. Peroxide value was also found to increase during refrigeration storage of sausage from 3.05 MeqO 2 /kg at day 0 to 11.46 MeqO 2 /kg on day 18. Vegetable-incorporated chicken sausages were successfully developed by incorporating vegetables in the formulation without any deteriorating effect on the sensory attributes and acceptability of the product. The results indicate that incorporation of vegetable in chicken based sausage like product can have the added dual benefit of improved nutritional quality and antioxidant.
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    Process optimization of soybean and mushroom incorporated steamed bread
    (Department of Food Technology, 2022) Osti, Subash Chandra
    Steamed bread was prepared with incorporation of oyster mushroom powder and defatted soybean powder, aiming to minimize wheat flour and maximize soybean and mushroom powder content in the mix. Design expert software, mixture design was used for experimental design, in which level of soybean and mushroom powder within a range from 0 to 20 parts of each for formulation of steamed bread with varying refined wheat flour content by 80 to 100 parts. Similarly, Response surface methodology, central composite design was used to design another experiment for optimization of fermentation time within a range from 30 to 90 min at 35±2°C and steaming time for 10 to 20 min at normal atmospheric condition. For microbiological study, steamed bread samples were packaged in 40 μ LDPE zip lock bags and stored at ambient and refrigerated storage conditions at 30±2ºC and 5±1ºC respectively. Both samples were subjected to microbiological assessment daily until the microbial load had reached to a critical value of 5 log cfu/g. The optimum level of wheat flour, soybean powder and mushroom powder were found to be of 87.89, 10.03 and 2.08 parts respectively with magnitude of hardness, specific volume, spread ratio and L* (whiteness) were 2801.73 g, 1.75 ml/g, 1.58 and 73.87 respectively. Fermentation time of 67.04 min at 35±2°C and steaming time of 15.05 min under normal atmospheric pressure as optimized process conditions with magnitude of hardness, specific volume, spread ratio and L* (whiteness) were 2806.63 g, 1.74 ml/g, 1.49 and 75.07 respectively. Moisture, crude fat, crude protein, total ash, crude fiber and total carbohydrate content of optimized product on dry weight basis were found to be 41.20±0.23, 2.95±0.09, 18.16±0.17, 3.98±0.11, 0.99±0.09 and 73.13±0.47% respectively. Results of sensory evaluation showed that there was no significant difference (p>0.05) between soybean and mushroom incorporated steamed bread and the control product containing 100 parts refined wheat flour in terms of color and appearance, flavor, texture, taste and overall acceptability. Microbiological analysis of steamed bread packaged in 40 μ zip lock LDPE bags showed that the product was found to be safe for consumption within the first 5 days of storage under refrigerated storage at 5±1ºC and only a day at ambient storage at 30±2ºC. The cost and calorific value of the optimized product per 100 g was found to be NRs. 12 (as of 2021) and 230.35 Kcal respectively.
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    Technological and Nutritional Evaluation of Sel-roti
    (Faculty of Food Technology, 2013-05) Katawal, Surendra Bahadur
    Sel-roti is a popular and delicious rice-based, sweet, puffed, spongy, deep-fat fried, ring shaped doughnut like Nepalese indigenous food product prepared from the batter of rice flour, ghee and sugar. Sel-roti making technology is an indigenous technology of Nepal. A survey study of 126 respondents comprising different casts, ethnicity, religion, age, sex from different district of Eastern and Central Development Regions of Nepal was conducted to gather the information on ingredients, recipe, equipments and processing methods of Sel-roti by using questionnaires. The factors affecting quality, storage and shelf life and also production, marketing, socioeconomic and cultural aspects were gathered and documented. It showed that the variety and age of rice, type of ingredients, method of preparation, and storage condition influence the quality and self-life of Sel-roti. To study the effect of particle size of rice flour on the physical properties, sensory quality and textural attributes of Sel-roti, the soaked rice was ground into flour with the help of iron mortar and pestle, analyzed for particle size distribution by using standard sieves and separated into three particle size categories i.e. coarse (>890 µm), medium (450-225 µm) and fine (<120 µm). They were mixed in different proportions; analyzed their distribution and calculated mean particle diameter; prepared Sel-roti, and analyzed for bulk density & fat uptake; and sensory and texture attributes were evaluated by trained panelists. The experiments were conducted in triplicate. The results obtained showed good positive correlation between mean particle size and the bulk density (r = 0.97, p≤ 0.05) and a good negative correlation between mean particle size and fat-uptake (r = -0.90, p≤ 0.05). Also, good correlations of mean particle size with sensory texture attributes like smoothness (r = -0.97, p≤ 0.05), hardness (r = 0.99, p≤ 0.05), fracturability (r = 0.96, p ≤ 0.05), cohesiveness (r = -0.92, p ≤ 0.05), Stickiness (r = -0.76, p≤ 0.05) and oily mouth feel (r =-0.85, p≤ 0.05), but fair relation with chewiness (r = 0.65, p> 0.05) were found. The ANOVA and LSD of panel scores for each sensory attribute like appearance, taste, texture, flavor and overall acceptance showed significantly difference (p≤0.05) among treatments. From the same experiment the optimum particle size of flour i.e., 520±6µm was selected for good Sel-roti preparation. Processing parameters like soaking of rice, kneading of ingredients, ageing of batter, consistency of batter, frying temperature and time had significant effect (p≤0.05) on some physical properties and sensory quality of Sel-roti. From the same study the optimum processing parameters investigated were 2h(minimum) soaking time of rice; 10mim kneading time of ingredients for 250 g flour; 1.935DS/L corresponding velocity flow rate, 2.302cm/s or 25 ml water per 100g fresh flour; minimum 1h ageing time of batter; and 210°C(initial) frying temperature and 33S frying time. The frying medium had also effect on the quality of Sel-roti. Among the used ghee and oils refined soybean oil was selected. The result of the study of the effect of age of rice and ‘daun ‘ on the quality of Sel-roti revealed that daun is must for good Sel-roti preparation whereas age of rice had not significant effect(p>0.05). There were significant effect (p≤0.05) of ageing temperature and ageing time of batter on the biochemical parameters such as pH, acidity, reducing sugar and total sugar. On the comparison Sel-roti prepared from optimized process and recipe were found to be superior to Sel-roti prepared from traditional process. The physical properties of Sel-roti determined were 542kg/m 3, 10.78±0.55cm, and 1.93±0.16cm for bulk density, ring diameter and cross section diameter of Sel-roti respectively. The sensory properties of Sel-roti were ringed shape, light to reddish brown colour and grainy surface, moderate sweet taste, soft and little crunchy texture and sweetish and burnt sugar flavor characteristics to Sel-roti; and the proximate composition of Sel-roti were found to be as 4.68±0.10, 26.46±1.35, 0.30±.01, 0.16±0.02 and 68.41±1.44 on dry weight basis for crude protein, crude fat, ash, crude fibre and carbohydrate respectively and calorific value of Sel-roti was found to be 533kcal on dry weight basis. The texture attributes of Sel-roti were found to be 8.20±1.6, 6.01±1.4, 8.53±1.6, 7.33±1.5, 5.70±1.5, 9.47±1.6 and 15.00±3.0 for smoothness , hardness, fracturability, cohesiveness , stickiness, oily mouth feel and chewiness respectively.