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2011 - 2019132020 - 202313
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Subject: Processing and Food Engineering × Start date: 2010 × Type: Thesis × Thesis Type: M.Tech. ×
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Now showing 1 - 9 of 26
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    ThesisItemOpen Access
    Effect of different precooling methods and storage conditions on shelf life and quality of pear (Pyrus pyrifolia (Burm. F) Nakai)
    (Punjab Agricultural University, Ludhiana, 2022) Mahajan, Kashika; Gupta, S.K.
    The present investigation entitled “Effect of different precooling methods and storage conditions on shelf life and quality of pear (Pyrus pyrifolia (Burm. F) Nakai)” was conducted during the year 2021-22. Three methods of pre-cooling i.e; hydrocooling (HC), forced air cooling (FAC) and evaporative cooling (EC) were evaluated for postharvest quality of pear fruit under cold storage and ambient storage conditions. Two experiments were laid out viz (i) Optimization of precooling time of pear fruits using different precooling methods and (ii) Effect of precooling methods on storage life and quality of pear fruit under cold storage and ambient conditions. In the first experiment the data exhibited that HC took 130 minutes and FAC took 360 minutes to precool the pear fruits from 34.9oC to 5.2oC. However, the EC could not achieve the desired temperature to precool the pear fruit. In the second experiment the fruit were subjected to HC, FAC and EC treatments for requisite time period as determined in first experiment. The fruits were packed in corrugated fibre board boxes and stored in cold room (0-1⁰C temp and 90-95% RH) and at ambient conditions (28-32oC and 70-80% RH). The stored samples were evaluated periodically for various physiological and biochemical parameters. The data revealed that FAC was found to be the best precooling method to enhance the shelf life of pear fruits upto 60 days under cold storage conditions and 15 days under ambient storage conditions. The control fruits maintained the storage life upto 45 days under cold storage and 10 days under ambient conditions.
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    ThesisItemEmbargo
    Effect of different packaging films on storage life of tomatoes in consumer packages
    (Punjab Agricultural University, 2023) Pooja; Sharma, S. R.
    The present investigation was conducted to evaluate the effect of different packaging films on storage life of tomatoes in consumer packages. Five packaging films HDPE (25μ), LDPE (25μ), PP (25μ), shrink (15μ) and cling (15μ) were used to wrap the consumer packages made of corrugated trays. These film wrapped consumer packages were evaluated for postharvest quality of tomato cv. Punjab Varkha Bahar 4 under ambient and cold storage conditions. The physico-chemical parameters measured to determine the storage life of tomato were PLW, spoilage, firmness, colour, gas concentration, TSS, titratable acidity, total phenols, ascorbic acid and lycopene content at 0, 3, 6, 9, 12 and 15 days of storage under ambient storage conditions (17.4-19 °C, 25-28% RH) and at 0, 7, 14, 21, 28 and 35 days of storage under cold storage conditions (10±1°C and 90-95% RH). Cold storage of tomato was found to be better than ambient storage. Tomato packed in cling film wrapped consumer packages were found to be best for 9 days of storage life with desirable physical and chemical attributes as compared to control packages which maintained the storage life up to 3 days only under ambient storage conditions. Tomatoes packed in cling film wrapped consumer packages proved to be the best for 21 days of storage life with minimum weight loss and spoilage, desirable fruit firmness, better colour and other quality parameters as compared to control packages which maintained the storage life up to 7 days only under cold storage conditions.
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    ThesisItemRestricted
    Storage behavior of selected food grains in hermetic bag and cocoon bag
    (Punjab Agricultural University, Ludhiana, 2023) Yadav, Shubham; Mahesh Kumar
    The present study has been conducted to observe the storage behavior of selected food grains (paddy, wheat and canola) in hermetic bag and cocoon bag. Storage parameters like moisture content, bulk density, thousand grain weight, insect count, mould affected grains percentage, broken grains percentages, grain damaged percentage, level of oxygen and carbon dioxide concentration inside cocoon bag, germination rate and internal environment conditions like temperature and relative humidity has been observed during the study. In case of canola oil seed, acid value of extracted oil has been examined. The techno-economic feasibility of stored grains under prescribed condition has been evaluated out using standard methods. The grains have been stored for 6 months in different types of plastic bags like 1-layer (HDPE), 2-layer (HDPE and PP), 3-layer (2-layer HDPE and PP), jute bag and cocoon bag. The cocoon bag has showed marginal effect on moisture content of food grains viz. 0.50 % variation for paddy, 0.31 % variation for wheat and 0.66 % variation for canola as compared to other storage bags. There was limited variation in bulk density of paddy 0.01 %, wheat 0.006 % and canola 0.0338 % while 1000 grain weight was changed with a very small variation of 0.1448 % for paddy, 0.1117 % for wheat, and 0.9918 % for canola in cocoon bag. After 6 month of storage, 4.6 % oxygen and 78.0 % carbon-di-oxide concentration were maintained inside the cocoon bag and no insect activity was observed in the cocoon bag stored grains and there was no mould affected grains. Broken grains percentages were changed with a very small range in cocoon bag 0.90 to 0.98 for paddy, 1.40 to 1.81 for wheat, and zero for canola. The acid value of canola oil was found to be in the range of 0.97 mg / 100 g of KOH to 0.99 mg / 100 g of KOH in cocoon bag. The profit margin has been worked out be highest in cocoon bag (12.13 %) due to minimum grain loss and limited changed in quality parameters followed by 3-layer hermetic bag with 2.65 % and 1-layer, 2-layer and jute bag has negative profit margin i.e., loss due to damaged grain by insects. Cocoon bag can be adopted through proper training and demonstrated for safe grains storage.
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    ThesisItemEmbargo
    Studies on the impact of vacuum and nitrogen flush packaging on natural ageing of basmati rice
    (Punjab Agricultural University, Ludhiana, 2022) Aggarwal, Kanika; Mittal, Tarsem Chand
    The present research was done to study the impact of vacuum and nitrogen flush packaging on natural ageing of basmati rice. Vacuum and Nitrogen flush packaging is becoming increasingly common. Vacuum packaging is considered to be beneficial for basmati rice storage as it can effectively retard the rice deterioration. Whereas, nitrogen is used as a filler gas to maintain the shape of pack by avoiding packaging collapse due to dissolving of carbon dioxide into the food product. It prevents collapse of package because it is less soluble in fat and water. So, these enable the significant extension in shelf life of product. Storage of the basmati rice in different packaging material, under different conditions, at different period of time and temperatures affects its physicochemical, cooking and textural properties. Two basmati rice varieties (Pusa Basmati 1121 and Pusa Basmati 1718) were stored in three different packaging materials using three different packaging methods for six months under ambient conditions. Packaging materials used were triple layer vacuum packaging material (Pe + Adhesive + Evoh + Adhesive + Pe) (TLM 95 gauge); low density polyethylene (LDPE 100 gauge) and laminated aluminium foil packages (APM 100 gauge). About half kg of Pusa Basmati 1121 paddy and Pusa Basmati 1718 was filled in these bags. Total six bags of each type were accordingly filled. These bags were normal sealed, vacuum packaged and nitrogen flushed. Samples were drawn from each bag at an interval of one month and assessed for various quality parameters like changes in cooking, physicochemical and textural properties during storage. On storage the cooking parameters like optimum cooking time and solid loss in gruel decreases whereas cooking coefficient, water absorption ratio and volume expansion ratio increases. The moisture content, amylose content decreases while aroma, hardness and other textural properties increases with increase in storage period. Storage in triple layer vacuum packaging material under vacuum conditions was founded to be the best to maintain a better quality.
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    ThesisItemOpen Access
    Shelf life enhancement of kinnow through active packaging
    (Punjab Agricultural University, Ludhiana, 2021) Pawandeep Kaur; Kanojia, Varsha
    Kinnow comes in “Mandarin” group of citrus fruits, which produced prominently in India and Pakistan and being perishable in nature. It has the shortest shelf life among all other citrus fruits. The present study was carried out to enhance the shelf life of kinnow by active packaging. RSM with BBD for 3 independent variables at 3 levels viz. dose of scavenger (35grams), fungicide concentration (3-7%) and polythene thickness (100-200guage) was used to optimize the process parameters to maintain the quality of fruit with respect to selected responses i.e., gas composition, physiological loss in weight, firmness, total soluble solids, titrable acidity, ascorbic acid, color difference, microbial load and shelf life. The samples treated with fungicide was packed in LDPE wrapped carton box with O2, CO2 and C2H4 scavenger and stored in cold chamber (5-7°C and 90-95% RH) and were monitored at regular intervals. It was observed that physiochemical properties of kinnow fruit were significantly affected by active packaging (p< 0.05). Optimization was done aiming at minimize O2, CO2, physiological loss in weight, total soluble solids, color difference, microbial load and maximize firmness, titrable acidity, ascorbic acid, shelf life while the process parameters should be within range. The optimized conditions for active packaging of kinnow fruit was 5 grams dose of scavenger, 6.83% fungicide concentration and 192.12 guage of polythene thickness. Corresponding to these variables, the values of O2, CO2, physiological loss in weight, firmness, total soluble solids, titrable acidity, ascorbic acid, color difference, microbial load and shelf life were 12.84%, 3.75%, 7.34%, 4.44 kgf, 9.2°Brix, 1.72%, 35.28 mg/100ml, 0.55, 4.87x103 cfu/ml and 69 days respectively. The overall desirability was 0.812. Value of percentage deviation for validation was less than 5% for all the responses which indicating the precision and reliability of the study.
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    ThesisItemRestricted
    Osmo-solar drying of pineapple slices with honey as osmotic medium
    (Punjab Agricultural University, Ludhiana, 2021) Bassi, Saurabh; Iqbal Singh
    Pineapple fruit is high in minerals and vitamins. It has moisture content of about 90% due to which it has perishability and limited shelf life. Osmotic dehydration is a technique for partially dehydrating water-rich foods; uses less energy than any other drying method. During the present study, the pineapple slices were partially osmotically dehydrated using honey as osmotic medium with the aim to prepare a healthy and nutritive pineapple slices. The osmomechanical drying process was optimized using RSM technique. The process parameters taken for osmotic drying were KMS concentration (0.5,1.0,1.5%), immersion time (24, 36, 48 hours) and honey pineapple ratio (2:1, 3:1, 4:1) whereas the quality was measured by quantifying ascorbic content, change in colour, water activity and overall acceptability (9-point hedonic rating scale). The mechanical drying was carried out at temperature of 60°C ± 3°C in tray dryer with trays having skewed rods. The pineapple slices were dried upto 15.5 to 18% final moisture as further drying becomes difficult due to drying of honey layer on the surface that prevents water movement from inner layers of pineapple. The optimum conditions were found to be 1.5% KMS concentration, 24 hours immersion time and 2.66:1 honey pineapple ratio. The quality parameters at optimum conditions were found as ascorbic acid content- 48.03 mg/100g, aw -0.603, ∆E- 23.31 with overall acceptability 74.7%. The optimum conditions were verified and the experimental values were found within significant limits. The osmo-solar drying of pineapple slices was carried out at optimum conditions with cabinet temperature variation from 28°C-55°C. The drying kinetics was studied using four drying models and two term model was found to have best fit for both mechanical and solar drying. The storage study was undertaken for osmo-solar dried slices in which the slices were packed in vacuum pack, laminated aluminium pack and LDPE and kept under ambient conditions. Vacuum packaging was found to have lesser degradation of quality in comparison to LAP and LDPE packaging. Solar drying of dehydrated pineapple slices had a benefit-cost ratio of 1.37, whereas mechanical drying yielded a ratio of 1.13. Solar drying of dehydrated pineapple slices had a considerably higher benefit-cost ratio than mechanical drying which demonstrates its feasibility over mechanical drying that makes energy efficient process.
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    ThesisItemOpen Access
    Development and fabrication of a power operated low-cost small-scale fruit and vegetable grading machine
    (Punjab Agricultural University, Ludhiana, 2021) Awasthi, Anusha; Satish Kumar
    Investigation was carried out to develop, fabricate and evaluate performance of a power operated, multi-commodity low-cost small-scale fruit and vegetables grading machine for nearly spherical commodities viz onion, tomato, lemon, sweet lime, pear, beetroot, eggplant and apple guard. The grader consisted of main frame, feed hopper, grading belt with variable speed 1.0 hp electric motor, grading cum directional bar with speed regulated DC motors and collection spouts. Design parameters were geometric mean diameter (GMD), angle of external friction (AoEF) and angle of repose (AoR). Experiment was designed with response surface methodology (RSM) for optimizing the input parameters i.e., belt speed, grading bar speed and grading bar angle for responses viz., grading capacity and grading efficiency. Model validation was also carried out. The range of GMD, sphericity, AoEF and AoR varied between 43.45-60.46 mm, 0.878-0.934, 21-30º and 23-30º respectively for all commodities. Grading capacity and efficiency of selected commodities were significantly affected by input parameters. The quadratic model was adequate model for all the responses of input variables. The grading capacity showed positive relationship with belt speed, grading bar speed and grading bar angle in all commodities. However, grading efficiency was negatively affected by belt speed, positively affected by grading bar speed in all the commodities except tomato. The grading bar angle showed positive relation with grading efficiency in all commodities except onion and beetroot. The model was validated at 10 % level of significance. Overall grading capacity and grading efficiency ranged between 157-584 kg/h and 55.00-93.30% irrespective of the commodity.
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    ThesisItemOpen Access
    Development of hybrid processing technique for production of modified polysaccharide gel and powder from aloe vera (Aloe barbadensis Mill.)
    (Punjab Agricultural University, Ludhiana, 2021) Roy, Tapas; Alam, M. S.
    Experiments were carried out to develop hybrid processing technique for production of modified aloe polysaccharide (MAP) gel and powder from aloe vera. The modified aloe gel was developed by adding various concentration of cellulase enzyme (6-12mg/L) and treating it with different temperature (30-50oC) and time (60120 min) combination in order to degrade the molecular weight of native polysaccharide. The MAP gel developed under optimized condition was exposed to different foaming pre-treatments by adding foaming agents (soy protein isolate; glycerol mono stearate), foaming stabilizer (carboxymethyl cellulose) and whipping for different time period. The foamed aloe polysaccharide juice was optimized based on different responses like foam expansion, foam density, foam stability and average diameter of bubble size for each foaming agent by using different levels of soy protein isolate (3-7% w/v), carboxymethyl cellulose (0.1-0.5%) and whipping time (1-5 min); glycerol mono stearate (1-4%), carboxymethyl cellulose (0.1-0.5%) and whipping time (1-5 min) using 3 factors Box-Behnken design under Response Surface Methodology (RSM) technique. Both SPI and GMS foamed modified aloe polysaccharide (MAP) juice developed under optimized condition were converted to powder by varying drying bed thickness (1-5mm), drying air temperature (50-70oC) and compared with powder developed with non-foamed aloe juice with same drying condition. The study revealed that for development of modified aloe polysaccharide gel considering minimum TSS, maximum colour (L value), maximum optical density, maximum viscosity, maximum polysaccharide content and molecular weight the optimized condition obtained were 0.63% cellulase enzyme concentration, 61 min of exposure time and temperature of 37oC witnessing overall desirability of 0.893. The optimum foaming process parameters obtained for SPI and GMS foamed MAP gel considering minimum foam density, maximum foam expansion, maximum foam stability and maximum average bubble diameter were 6.91% SPI, 0.41% CMC and 4.86 min of whipping and 3.87% GMS, 0.39% CMC and 4.89 min of whipping with desirability of 0.885 and 0.889 respectively. Based on nutritional quality, the GMS foamed MAP powder developed through foam mat drying (3mm drying bed thickness and dried 50oC drying air temperature) retained significantly higher functional and nutritional qualities attributes followed by SPI treated MAP powder and fresh aloe powder.
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    ThesisItemOpen Access
    Optimization of drying techniques for extraction of bioactive compounds from guava (Psidium guajava L.) leaves.
    (Punjab Agricultural University, Ludhiana, 2021) Ishwinder Kaur; Mahesh Kumar
    Guava is known to have high nutritive value. Several health benefits of guava leaves have also been reported. However, the information on drying, modelling parameters and effect of drying on bioactive compounds is limited. The leaves of guava varieties Shweta and Purple Guava were dried using shade drying, tray drying (50°C, 60°C and 70°C) and microwave drying (360 W, 540 W and 720 W) approaches. To explain the drying data 19 models were evaluated. The drying data was best explained by Page model and Verma model in shade drying; Midilli and Kuck model, Jena and Das model at 70˚C tray drying; Midilli and Kuck and Logarthmic model for 360 W microwave drying in Purple Guava and Shweta, respectively. In both the guava varieties L*, a*, b* values were higher in fresh leaves in comparison to shade, tray drying and microwave drying methods. In Purple Guava, the rehydration capacity was highest (1.89) at 500C in tray drying, while in Shweta, it was highest (1.75) at 720 W in microwave drying. The total phenol content in fresh Purple Guava leaves was highest i.e 580.18 mg GAE/ mg dry weight among all drying conditions, while in Shweta the highest phenol content i.e 646.81 GAE/ mg dry weight was attained by 600 tray drying. In case of Purple Guava leaves powder, the highest (208.62 mg QE/ mg dry weight) flavonoid content was noted for 500C tray drying. The total flavonoid content decreased during the storage period irrespective of the guava variety.