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ThesisItem Restricted Processing of selected varieties of Punjab Potato (Solanum tuberosum) to produce flakes and flour using hot air drying(PAU Ludhiana, 2013) Shweta Goyal; Mahesh KumarInvestigation were carried out to produce flakes and flour from potatoes. Two popular variety of potatoes in the state of Punjab namely Kufri Pukhraj and Kufri Jyoti were selected for this purpose. The raw potatoes procured from the local vegetable market were peeled, boiled in a microwave. A mash was produced by crushing boiled potatoes followed by dipping in 0.2%KMS solution for 1 hour to remove the sugars. The drained mashed potatoes were dried at 50°C, 60°C & 70°C in the layers of 5, 6 & 7 mm. The prepared mash was also dried in a solar dryer. It consumed about 900-1290 min to dry at 50°C & 70°C. Effective moisture diffusivity varied between 1.43x10-10 & 3.98 x 10-10 m2/sec for tray dried sample in comparison to 2.79 x 10-10 to 4.39x10-10 m2/s for solar dried. The prepared flakes were grounded to produce the flour that was stored in HDPE and LDPE pouches, Al laminate & glass bottles and kept at room temperature. The parameters like moisture content, colour, NEB, flavor etc. were estimated at regular interval of 15 days. The process parameters, temperature & thickness were optimized by RSM technique for the responses, namely rehydration ratio (RR), shrinkage ratio (SR), reducing sugar, swelling index (SI), starch content, colour (L value) and overall acceptability (OA). The vital values of these parameters were 1.83-2.8 (RR), 0.76-1.2 (SR), 0.012-0.189 (reducing sugar), 1.52-2.14 (SI), 5.82-6.45 (starch content), 47.4-53.12 (L value) and 7.06-7.52 (OA) respectively. The optimized values of temperature & thickness lie in the range of 61.27-58.44°C & 6.56-5.86 mm respectively for tray & solar dried, Kufri pukhraj & jyoti potato. From the study, it was concluded that the log model showed high adequacy of fit & best result was obtained for laminate packed potato flour.ThesisItem Open Access STUDIES ON DRYING BEHAVIOUR AND QUALITY OF GARLIC (Allium sativum L.) USING HYBRID DRYING TECHNIQUES(PAU Ludhiana, 2013) Jaspreet Singh Grewal; M. S., AlamInvestigations were carried out to study the drying kinetics of garlic slices i.e 3mm size for selected hybrid drying techniques, convective-cum-microwave (CCM) and fluidized-cum-microwave (FCM). The experiments were conducted using completely randomized design (CRD) by varying drying parameters viz. KMS concentration (0.1-0.5 %), drying air temperature (55-75°C) and microwave power level (810-1350 W). The garlic slices were dried to 63(±1) % d.b moisture content by convective tray drying/fluidized bed drying and further dried up to 6(+1) % d.b by microwave drying. Five empirical models were fitted to the kinetics data of convective, fluidized and microwave drying and their adequacy of fit was investigated. Response surface methodology (RSM) was employed for optimization of drying process parameters for CCM and FCM drying using 3-factor Box-Wilson design. Optimization was done on the basis of minimum drying time, specific energy consumption, shrinkage ratio, texture (hardness), non enzymatic browning, maximum rehydration ratio, colour (L-value) and overall acceptability. Dried garlic flakes developed under optimized drying process conditions for both the hybrid drying techniques were packed in three packaging material (Aluminum, LDPE and HDPE bags) and stored under ambient condition (220C to 320C temperature, 45 to 55 % RH). In order to develop garlic flakes, the total drying time varied from 115 to 187.17 and 48 to 72.17 min for CCM and FCM drying respectively. The average effective diffusivity increased with increase in drying air temperature and power level. Among various models checked for their adequacy of fit to the experimental data of drying, the Two term exponential model for convective tray drying, logarithmic model for both fluidized bed and microwave drying were found to be the best fitted model representing the drying kinetics. The optimized drying process parameters obtained were: 0.5 % KMS concentration, 59.41ºC temperature and 810 W power level; 0.1 % KMS concentration, 63.92ºC temperature and 810 W power level for CCM and FCM drying respectively. The dried garlic flakes packed in Aluminum packs was adjudged to be the during three months storage periodThesisItem Open Access OPTIMIZATION OF MODIFIED ATMOSPHERE PACKAGING FOR CUCUMBER (Cucumis sativus L.)(PAU Ludhiana, 2013) Kandale Pallavi Uttamkumar; Preetinder KaurThe present study was undertaken to optimize Modified Atmosphere Packaging (MAP) for cucumber (Cucumis sativus L.) to obtain the maximum shelf life on the basis of quality attributes and sensory evaluation during the storage study experiment. Respiration and transpiration rates of cucumber at different temperatures viz. 5, 10, 15°C and ambient (18.6°C) were determined. The respiration rate was described assuming the combined type of inhibition in the enzyme kinetics model. Arrhenius relationship was used to explain the temperature dependence of respiration rate, respiratory quotient and transpiration rate of fresh cucumber. A theoretical analysis for design of MAP for selection of appropriate packaging film was carried out by matching the data obtained in respiration study with the permeabilities of commercially available packaging films. Cucumber was packed in LDPE and stored under different conditions such as film thickness: 100, 150, 200 gauge; package fill weight = 200, 300, 400g; level of perforations: 0, 2, 4; storage temperature: 5, 10, 15°C. The qualitative analysis of cucumber throughout the storage study was done in terms physiological loss in weight, total colour difference, firmness, total chlorophyll, and ascorbic acid. Sensory evaluation was done on the basis of visual appearance, odour rating and water accumulation. The study also revealed that the low temperature storage better retained the quality and quantity of fresh cucumber during its storage. MAP along with low temperature storage helped in enhancing shelf life of fresh cucumber upto 28 days. The optimized conditions obtained for shelf life extension of cucumber under MAP by using response surface methodology was temperature: 6.10°C, film thickness: 135.01 gauge, fill weight: 274.61 g, perforations: 0 and the expected shelf life of fresh cucumber at optimized conditions was 21 days.ThesisItem Open Access Impact of supplementation of broccoli products (Brassica oleracea L var italica plenck) on blood glucose and lipid profile of non-insulin dependent diabetics(PAU, 2014) Madhu; Kochhar, AnitaNinety non-insulin dependent male diabetics in the age group of 40-60 years were selected. Fresh floret and leaves of broccoli were washed, blanched, dried, powdered and chemically analyzed for nutritional composition. Ten products, five with broccoli floret and five with broccoli leaf powder namely Missi Roti, Vegetable Dalia, Dhokla, Channa dhal and Barley snacks were developed and evaluated organoleptically. Incorporation of broccoli floret powder at 5-15% and broccoli leaves powder at 5-10% was highly acceptable in all five products. The selected subjects were divided into three groups I, II and III, each group having thirty subjects. The subjects of group I was given no treatment, group II was given 10 gm of broccoli floret and group III was given 10 gm of broccoli leaf powder in form of missi roti for a period of 3 months along with nutrition counselling. Subjects were imparted nutrition education regarding the disease, its dietary management, health benefits of broccoli and physical exercise. The mean energy, carbohydrates, protein and fat intake decreased significantly (P≤0.01) in the subjects of group II and III and a non significant decrease (P≤0.01) was seen in the subjects of group I. Significant (P≤0.01) percent reduction was observed in fasting blood glucose level by 17.2 and 11.7, post prandial glucose level by 14.1 and 11.9, total cholesterol 8.4 and 9.5, triglycerides 10.7 and 6.2, LDL-C 11.1 and 8.0, VLDL-C 10.5 and 9.4, and an increase in HDL-C 7.3 and 3.7 in the subjects of group II, and III . The ratio of total cholesterol to HDL-C reduced to 14.6, and 9.4 per cent and LDL- C to HDL-C reduced to 16.6 and 11.2 per cent in the subjects of group II, and III respectively whereas non significant changes were observed in the subjects of group I . There was also a significant decrease (P≤0.01) in the blood pressure of the subjects in group II and III and a non significant decrease (P≤0.01) was seen in the subjects of group I. There was a significant increase (P≤0.01) in KAP scores obtained by the subjects of group II and III and a non significant increase (P≤0.01) was seen in the subjects of group I. It can be inferred from the results that supplementation of brocoli floret and leaf powder along with nutrition counselling significantly improved the nutritional status of the diabetics.ThesisItem Restricted Optimization of Osmo-Cum- Microwave Dehydration Process for Oyster Mushrooms (Pleurotus sajor-caju)(PAU, 2014) Ramya, H.GInvestigations were carried out on “Optimization of Osmo-Cum-Microwave Dehydration Process for Oyster Mushrooms (Pleurotus sajor-caju)”. The effect of various independent process parameters on mass transfer kinetics (water loss and solute gain) was studied. These process variables include solution concentration (salt: 10–20%; salt-sugar: 15 – (45- 65) °B), solution temperature (30–60° C) immersion time (15–240 min) and solution to fruit ratio (4:1 to 8:1). Water loss and solute gain increased with solution temperature, solution concentration, duration of osmosis over the entire osmotic dehydration process. The moisture content reduced from 90.3 to 45 - 48 % (wb). Effective water diffusivity varied between 1.13 - 2.58 x 10-9 m2/s and 1.59 - 3.0x 10-9 m2/s, solute diffusivity between 3.92 - 9.9 x 10-10 m2/s and 9.44 x 10-10 - 1.02 x 10-9 m2/s respectively for mushrooms treated with salt and salt-sugar respectively. Power and Page models showed the highest adequacy of fit for osmotic dehydration of mushrooms treated with salt and salt-sugar solutions respectively. Optimum operating conditions found were: solution temperature – 45o C, immersion time – 53.54 min, salt concentration – 14.09% and solution to fruit ratio 6.08:1. Corresponding optimum values for mushrooms treated with salt solution were, 38.13, 2.1 and 36.02 (g/100 g initial mass) for water loss, solute gain and weight reduction respectively. Optimum operating conditions for mushrooms treated with salt-sugar were, solution temperature – 42.3° C, immersion time – 44.21 min, salt-sugar concentration – 15 %: 52.57° B and solution to fruit ratio 4.99:1. At these optimum values, water loss, solute gain and weight reduction was 41, 2.15 and 38.6 (g/100 g initial mass). Microwave dehydration of pre-osmosed mushroom was carried out at three power levels of 540, 810 and 1080 W. Moisture content of dehydrated mushroom reduced from 45 - 48 to 5.7 – 6 % (wb). Effective moisture diffusivities varied between 1.18 - 2.027x10-9 m2 /s and 1.29 - 2.65x10-9 m2 /s for mushrooms treated with salt and salt-sugar respectively. Logarithmic model showed the highest adequacy of fit for microwave dehydration in the both the cases. The quality of dehydrated mushrooms viz. colour, texture, rehydration ratio, shrinkage ratio and overall acceptability were analyzed for optimization of drying process variables. The optimum condition of microwave drying found were; microwave power level - 810W, L - 48.77, a - 4.41, b - 10.91, E - 10.24, hardness - 1639.56 g-f, chewiness - 429.05 g/cm2, RR - 1.94, SR - 0.93, aw - 0.461, ascorbic acid - 1.8 with an overall acceptability of 80.5 %, for dehydrated mushrooms treated with salt. For mushroom treated with salt-sugar, optimum conditions of microwave drying found were; microwave power level - 810 W, L - 46.66, a - 5.8, b - 15.74, E - 14.15, hardness - 1342.05 g-f, chewiness - 1270.97 g/cm2, RR - 1.89, SR - 0.93, aw - 0.453, ascorbic acid - 1.87 with an overall acceptability of 83 %. The best dried product obtained through optimization was packed in three materials viz; LDPE, HDPE and LAP and stored under refrigerated and ambient conditions for 3 months. The quality attributes of stored product like colour, texture, rehydration ratio, moisture content, water activity, ascorbic acid and overall acceptability were evaluated at 15 days interval. The dried mushrooms packed in laminated aluminium were found to be highly acceptable up to 3 months of storage.ThesisItem Restricted Assessment of antioxidant and functional properties of Jamun (Syzygium cumini L.)(Punjab Agricultural University, 2014) Kapoor, Swati; Ranote, P.S.The investigation was carried out to assess the antioxidant and functional properties of jamun, optimization of the supplementation levels of jamun powder in various food products namely pear juice, papaya fruit bar, extruded snacks and chapatti and to investigate the shelf life of jamun supplemented products. The physico-chemical and bioactive analysis showed that jamun powder was a good source of crude fibre, ash, anthocyanins and total phenolic content. Freeze dried jamun powder retained better bioactive compounds and had 44.27, 17.53, 13.35 and 5.75 per cent higher ascorbic acid, anthocyanins, total phenols and antioxidant activity, respectively as compared to hot air dried jamun powder. Optimum supplementation level of jamun powder in the products was selected on the basis of sensory evaluation and could be supplemented up to 4, 5, 10 and 3 per cent in pear juice, papaya fruit bar, extruded snacks and chapattis, respectively. Color analysis revealed lower L*, b* and higher a* values for all the jamun powder supplemented products as compared to control except papaya fruit bar where a* values decreased. Blending of jamun powder with pear juice, papaya fruit bar, extruded snacks and chapattis, enhanced bioactive components and per cent increase in antioxidant activity was 18.13, 56.41, 96.55 and 32.08, respectively than control samples. Supplemented pear juice showed higher mean values for titratable acidity (0.33 %), reducing sugars (7.97%, dextrose) and total sugars (10.37%, dextrose) as compared to control. For supplemented papaya bar slightly lower mean values were recorded for moisture (19.45%), TSS (76.26˚B), reducing sugars (22.23 %, dextrose) and total sugars (63.35%, dextrose) as compared to control. Not much variation was observed in total ash, crude fibre and crude protein content of control and supplemented samples. Decrease in expansion ratio, water absorption index and increase in bulk density, hardness and water solubility index was observed in supplemented extruded snacks. After supplementation with jamun powder, ash content increased by 4.31 per cent and fibre content increased by 5.82 per cent in chapattis. Freeze dried jamun powder supplemented chapattis were softer than chapattis supplemented with hot air dried jamun powder. Negligible effect of drying method and storage period on total ash, crude fibre and crude protein content of the jamun powder supplemented products was observed during 6 months of storage. During storage period, all the bioactive compounds and antioxidant activity decreased significantly (p≤0.05) in control and supplemented samples. Storage studies showed that jamun powder supplemented products could be stored safely at ambient temperature without significant changes in sensory attributes. All the jamun powder supplemented products were microbiologically safe during entire storage period. The products supplemented with freeze dried jamun powder were found nutritionally superior in terms of bioactive compounds and antioxidant activity as compared to hot air dried jamun powder supplemented products.ThesisItem Open Access Effect of different drying techniques on the quality of red chilli powder(Punjab Agricultural University, Ludhiana, 2016) Gupta, Shuchi; Sharma, S.R.The experiments were carried out to analyze the effect of different drying techniques during chilli processing on final recovery of powder and its quality. Red chilli variety Punjab Sandhoori was given physical treatment of slitting to half of the lot and making two lots as whole and slit chillies which were then dried by three different techniques namely sun drying, improved sun drying and mechanical drying technique at 50ºC, 60ºC and 70ºC. The final moisture content ranged from 1.74 to 6.06 (%db). The time required to achieve the equilibrium moisture content were 33, 26, 19, 16 and 9 h for whole chillies and 30, 20, 16, 13 and 6 h for slit chillies whereas the time required to achieve 7 (%db) moisture content were 32.53, 24.92, 18.09, 15.11 and 8.29 h for whole chillies and 25.42, 17.28, 12.96, 11.44 and 5.03 h for slit chillies for sun drying, improved sun drying and mechanical drying at 50°C, 60°C and 70°C respectively. The recovery of chilli powder varied under different drying techniques from 17.50 to 23.25%. Quality of chilli powder was determined in terms of ascorbic acid, capsaicin content, colouring matter and oleoresin content. Page model fitted well to the drying data. Mechanical drying technique at 50ºC gave the best results. Quality of the product reduced significantly during sun drying and mechanical drying at 70ºC. Improved sun drying technique was much better than sun drying technique in terms of drying behavior and quality parameters.ThesisItem Open Access Development of nanoparticles embedded bio-degradable polymers for packaging and storage of fruits and vegetables(Punjab Agricultural University, Ludhiana, 2016) Gautam, Rakesh Babu; Satish KumarThe investigations were carried out to develop nano-particle embedded bio-degradable polymers. The experiment was designed using RSM to optimize process variables (pH & Sonication levels). The ingredients viz. soy protein/ whey protein isolate (5%), glycerol (1.5%) and titanium dioxide (TiO2) (5%) were blended to develop film as a function of sonication (0-100%) and pH levels (7-10). The predicted and experimental values of the responses were statistically analysed for model validation. The film was used for individual packaging and storage of guava and tomato under ambient (21±2ºC and 40-55% RH) and cold storage conditions (4±1ºC and 90-95% RH). It was observed that thickness, weight, moisture content, moisture absorption, water solubility, water vapour transmission rate, and melting temperature (Tm) of developed film decreased with increasing pH and sonication level. However, area, viscosity, tensile strength, elongation at break, gas transmission rate and overall colour change (∆E) followed reverse trend. Mechanical tests revealed the plasticizing effect of nano-particles on the bio-film. Higher pH improved the barrier as well as mechanical properties. The developed films had an opaque appearance due to the presence of titanium di-oxide. Melting temperature (Tm) and SEM of soy protein isolate / whey protein isolate showed improved cross-linking bonding and homogeneous structure due to sonication application. The optimized value of process variables as predicted by RSM were pH:8.5 and sonication level:60%. Overall, TiO2 embedded SPI and WPI based films at optimized values of process variables resulted in improvement in physical, chemical, mechanical, optical and thermal properties and having complete degradability in about 140 days. Individually wrapped tomatoes and guavas can be safely stored for 16 days under cold storage conditions compared to 6-7 days in unwrapped. Soy protein isolate based film was found to be best.