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2003 - 200912010 - 20192
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Subject: Agricultural Engineering × Thesis Type: Ph.D ×
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Now showing 1 - 3 of 3
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    ThesisItemOpen Access
    Development of Solar Energy Based Inclined Plate Honey Moisture Reduction System
    (Punjab Agricultural University, Ludhiana, 2019) Iqbal Singh; Sukhmeet Singh
    Honey is delicious, nutritious and has high medicinal value in comparison to other sweeteners. Honey is usually extracted from comb as immature product which results in high moisture which makes it more liable to be fermented by osmophilic yeasts. So, it needs to be processed for moisture reduction, to delay crystallization and to overcome the problem of fermentation. The present study was undertaken to develop honey moisture reduction system based on solar energy with auxiliary electric heating. The system consists of a flat plate inclined at an angle. The plate is heated from the underside and honey for moisture reduction is re-circulated over it until desired moisture content is achieved. During testing, the moisture content of honey was reduced from 21.5% (w.b.) to 17% (w.b.). The moisture reduction system requires energy input for honey pumping, water pumping and water heating. The drying behavior and honey quality parameters affected by heating viz. HMF (Hydroxymethylfurfural content), diastase activity and colour difference from raw honey were investigated. The process parameters, water temperature and plate inclination were investigated in the range 40 to 70oC and 30 to 60o using four level full factorial design. The process parameters were optimized under simulated indoor conditions based on quality parameters and minimum energy input. The optimum water temperature and plate inclination have been found as 60oC and 60o. The solar energy based honey moisture reduction system has been validated at optimized conditions for quality parameters. The benefit cost ratio of the system considering the cost of raw and processed honey has been determined to be 3.90, thereby indicating that the developed system can be used profitably to reduce the moisture content of honey.
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    ThesisItemOpen Access
    Osmo-mechanical dehydration of Fig (Ficus carica L.) and its value addition.
    (PAU Ludhiana, 2012) Rajneesh Kant; Jarnail Singh
    The fresh fully matured fig fruits were procured from markets, orchard of PAU Ludhiana and Dera Baba Jaimal Singh, Beas, Punjab. The detailed nutritional, mechanical, physical and colour analysis of fresh fig fruit were carried out before undergoing osmo-mechanical drying. Osmotic dehydration followed by hot air drying and only hot air drying were carried out under different process parameters. The independent process variable was temperature for hot air drying. Concentration of osmotic agent, temperature of osmotic agent and fruit to solution ratio were independent variables for osmotic dehydration. Levels of temperature for hot air drying were 60, 70, and 80OC. Levels of concentration and temperature of osmotic agent (sucrose solution) were 50, 60, and 70OBx and 60, 70 and 80OC respectively. Similarly levels of fruit to solution ratio were 1:4, 1:5 and 1:6 (w/w basis). Process variables were standardized by carrying out experimental observations and score rating of hedonic scale. Response surface methodology was also adopted for optimization of these process variables. Water loss, solute gain and overall acceptability were response variables under central composite face centered design. The selected process conditions viz. concentration, temperature and fruit to solution ratio for desired product were 60OBx, 70OC and 1:5 respectively. Kinetics of hot air drying and osmotic dehydration were studied. Variations in drying rates and moisture content were investigated. The desired product was observed to be in the range of 18-20% moisture content. Sensory, nutritional and colour analysis of the osmo-mechanically dried fig slices was carried out during storage of six months under ambient conditions. The fig slices were found acceptable. The microbial count, water activity and color was comparable to market product and safe for human consumption. Protein, carbohydrates, and total fat were observed as 3.4g, 65.2 g, 1.2 g per 100g respectively. These remained intact as for fresh fig fruit these values were 1.50g,18.50g and 0.20g respectively. Vitamin A was observed as 180 IU and150 IU for dried and fresh fig respectively.
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    ThesisItemRestricted
    Optimization Of The Drying Process Of Garlic (Allium Sativum L.)
    (Punjab Agricultural University ;Ludhiana, 2003) Dhingra, Devinder; Shashi Paul