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  • ThesisItemOpen Access
    Optimization of a microwave assisted process for improving shelf-life of onion-ginger-garlic paste
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-10) Sanjana, Goli; Omre, P. K.
    The present work has been undertaken with the objectives of standardization of process parameter onion, ginger, and garlic paste using microwave heating based on quality characteristics and to study the shelf-life of the optimized paste. The study started with the development of the onion-ginger-garlic paste using salt and sunflower oil. After the development of the paste, microwave was used for heating treatment. Based on the temperature attained by the samples and quality characteristics, the three levels of independent parameters onion % in onion-ginger-garlic ratio (55%, 65% and 75%), sunflower oil concentration (40, 50 and 60ml/100g), microwave power (160, 320 and 480W) and processing time (1, 2 and 3min) were selected. Response surface methodology was used for designing the experiments and to select optimum levels of onionginger- garlic ratio, sunflower oil concentration, microwave power and processing time. Box- Behnken design with three replications was chosen to determine the levels of each experiment. Standardization of process parameters (i.e. onion % in onion-ginger-garlic ratio, sunflower oil concentration, microwave power and processing time) was carried out based on quality attributes (i.e. moisture content, total soluble solids, pH, total phenolic content, total flavanoid content, antioxidant activity, colour difference). The study showed that the moisture content ranged from 63.73 to 74.83%, A minimum total soluble solid of the paste was about 21.25 to 27.48ºBrix, pH from 4.406 to 4.804, total phenolic content from 110.88 to 117.56 mg GAE/100g, total flavanoid content from 277.3 to 292.275 mg CE/100g, Antioxidant Activity from 80.82 to 87.62 % and colour difference from 10.648 to 13.171. The study showed that all the independent parameters had significant effect on the responses. The optimum conditions of onion-ginger-garlic ratio, sunflower oil concentration, microwave power and processing time as computed by response surface methodology were 75:10:10, 60 ml/100g, 480W and 1.5min. After getting the optimized sample ratio with microwave treatment and control as untreated sample, shelf-life studies were carried out by storing the sample in air tight glass containers at ambient temperature (27 ± 2°C) and relative humidity (57±2%) for 60 days at 15 days interval. From the study it was observed that microwave treated sample got deteriorated from 58 days while the control sample from 27 days of storage. Colour difference in case of untreated sample was more compared to the treated sample.
  • ThesisItemOpen Access
    Optimization of process parameters for ultrasound assisted osmotically dehydrated papaya cubes followed by air-drying
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2020-08) Reddy, Nalla Bhanu Prakash; Shahi, N.C.
    Papaya (Carica Papaya. L) a tropical fruit having commercial importance due to its high medicinal and nutritive value. It is in general, called as a common man’s fruit as it is low priced with better nourishing capability and several health benefits. Post-harvest losses of papaya fruits happen along the whole value chain, moisture content is major contributing factor for the same. Drying or dehydration could be one of the techniques for reduction of water activity. Also, intermediate moisture foods (IMF) have become more common in recent years when compared to completely dehydrated ones. The problems that may occur during the osmotic dehydration process are undesirable effects like more sugar content in final product, shrinkage as a part of acceleration of water removal. Ultrasonication is one of the non-thermal and emerging technology which could accelerate the mass transfer rates during and after osmotic dehydration process and reduces the limitations faced in coonventional osmotic dehydration. Present study aims to produce product with a specific objective called more nutrition and health per gram. Experiments were conducted using central composite rotatable design (CCRD) with three independent variables at five levels. Independent variables selected for the experiment were osmotic solution concentration (43.2, 50, 60, 70 and 76.8 oBx), ultrasonication time (8.2, 15, 25, 35 and 41.8 min) and osmotic process time (83.2, 90, 100, 110 and 116.8 min). Responses selected were water loss (%), solid gain (%), colour difference (ΔE), ascorbic acid retention (%) and shrinkage ratio. The data from the experiments were analyzed using Design Expert software and the response function were developed using multiple regression analysis for each response. The optimum level of independent variables for development of dehydrated papaya cubes were 61.6 oBx of osmotic solution concentration, 17.7 minutes of ultrasonication time and 100.1 minutes of osmotic process time. The response values at optimum condition of independent variables obtained as 31.34% of water loss, 8.86% of solid gain, 24.82 of colour difference (ΔE), 63.78% of ascorbic acid retention and shrinkage ratio of 0.73.
  • ThesisItemOpen Access
    Optimiztion of process parameters for production of red wine from burans (Rhododendron arboreum) and its quality evaluation during storage
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2020-06) Yadav, Dhiraj Kumar; Khan Chand
    Burans (Rhododendron arboreum) flowers are widely grown in Uttarakhand and other hilly areas of India. The flowers of burans exhibit many therapeutic, nutritional and aromatic properties and have a number of uses in folk medicine. It is an evergreen tree which bears flowers with colour ranging from bright red to pink color. Burans flowers having antioxidant, anti-inflammatory, and anti- diabetic properties and is reported to inhibits the growth of cancer cells. As it contains natural red colour and various medicinal properties, the present study was undertaken to minimize waste and increase the shelf life of burans by processing it into fermented product (burans red wine). The experiments were conducted to study the effect of fermenting parameters on quality of red wine produced from Burans (Rhododendron arboreum) using yeast strain. The independent parameters selected were fermentation time (5, 8 and 11 days), temperature (30, 32 and 34°C), pH (3.5, 4.0 and 4.50) and total soluble solid (22, 24 and 26ºBx) to optimize them for production of burans red wine. Responses analyzed were alcohol by volume (%, v/v), titratable acidity (%), pH, total soluble solid (ºBx), reducing sugar (%), total sugar (%), antioxidant activity (%), total phenolic content (mg GAE/L) and total flavonoid content (mg QE/L). The data from all 29 experiments were analyzed using Design Expert 10.0.1 and the response function were developed using multiple regression analysis and second order model was fitted for each response. The optimum value of variables for maximum desirability of the prepared burans red wine were fermentation time 11 days, temperature 32.4°C, pH 3.85 and total soluble solid 23ºBx. The optimum value of responses were 12.27% of alcohol by volume, 0.578% of titratable acidity, 3.67 of pH, 8.49 ºBx of total soluble solid, 9.99% of reducing sugar, 13.25% of total sugar, 68.19% of antioxidant activity, 89.959 mgGAE/L of total phenolic content and 1091.205 mgQE/L of total flavonoid content. Significant (p<0.05) effect of process parameters were found in all responses. The prepared burans red wine were stored for 45 days and analyzed for all responses. During storage, alcohol by volume, pH, antioxidant activity, total phenolic content and total flavonoid content were increased however, titratable acidity, total soluble solid, reducing sugar and total sugar were decreased. This research has therefore proved that production of red wine from burans flower is an efficient and new approach towards improving processing efficiency, improving shelf life and improving economy.