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ThesisItem Restricted Assessment of extrusion behaviour of white maize(Punjab Agricultural University, Ludhiana, 2019) Arshdeep Singh; Baljit SinghThe present investigation was undertaken to explore the assessment of extrusion behaviour of white maize and their characterization. Response Surface Methodology (RSM) was used to optimize the extrusion process of white maize based extruded products. Central composite rotator design (CCRD) of response surface methodology was explored to evaluate the effects of independent variables, namely feed moisture content (14-18%), screw speed (400-550) and barrel temperature (125-175℃) on product responses specific mechanical energy (SME), bulk density (BD), water absorption index (WAI), water solubility index (WSI). White maize was subjected to extrusion by co-rotating twin screw extruder at varying processing conditions as per the central composite rotatable design. All the processing conditions had significant impact on product responses. Multiple regression equations were obtained to describe the effects of each variable on product responses. The product responses were most affected by change in feed moisture content, barrel temperature and to lesser extent by screw speed. The negative coefficient of moisture and temperature describes that the value of SME declined with increase of these two variables. Barrel temperature was found to elevate the expansion ratio and water solubility index. Optimization studies resulted in 12.50-16.2 % of feed moisture content, 145℃ of barrel temperature and 360-595 rpm of screw speed as optimum variables to produce acceptable white maize snacks. The products were stored for three months and were found acceptable at the end of three months.ThesisItem Open Access Utilization of lemongrass for shelf life extension and flavor enhancement of cookies(Punjab Agricultural University, Ludhiana, 2019) Amandeep Kaur; Amarjeet KaurStudy was carried out on “Utilization of lemongrass for shelf life extension and flavor enhancement of cookies”. Lemongrass was procured from department of Agronomy, washed, sliced and dried at two temperatures i.e. 35 and 500C for 16-18 hrs. Drying temperature which was selected was 500C for 16-18 hours. Lemongrass was ground into powder and analyzed for proximate composition, total phenols and phytochemicals. It was found to contain 8.1% moisture, 9.01% ash, 1.31% fat, 8.6% protein, 7.36% fibre and 65.28% carbohydrates. Total phenol content of powder was 0.13 g/100g as GAE gallic acid equivalent and flavonoids ranged from 0.49 g/100 g powder. The powder was incorporated in cookies at 0, 2.5% and 5% levels. Cookies containing 2.5% of lemongrass powder were found best on sensory evaluation scores. Cookies were stored in high density polyethylene (HDPE) for a period of 6 months. During this period changes in free fatty acid (FFA), moisture content, water activity (aw) and peroxide value (PV) were recorded. Although there was non significant increase in these constituents but cookies were found acceptable only upto 2 months organoleptically. The estimated cost for the cookies was Rs. 211.21/kg and Rs. 211.71/kg, respectively for 2.5 and 5% level of lemongrass incorporation as compared to Rs.210.71/kg for the control.ThesisItem Restricted Development of oat bran incorporated probiotic kulfi(Punjab Agricultural University, Ludhiana, 2018) Saini, Mehak; Jaspreet KaurKulfi was prepared from milk standardized to 5.5 per cent fat. Oat bran was given various pre-treatments i.e. size reduction, roasting and cooking before incorporating in kulfi mix. It was varied from 1.5 to 5 per cent of kulfi mix. The total solids, fat, protein, ash and carbohydrate content increased significantly (p≤0.05) on increasing the level of oat bran. Kulfi samples with 1.5 per cent roasted, unground and cooked oat bran had the highest overall acceptability scores .Crude fibre, NDF, ADF, ADL, hemicellulose and cellulose content increased significantly (p≤0.05) on adding oat bran. Kulfi mix was inoculated with probiotic culture i.e. Lactobacillus casei at 2 to 4 per cent of the kulfi mix. Viscosity of the kulfi mix and pH decreased, while acidity and viable probiotic count increased significantly (p≤0.05) on increasing the level of Lactobacillus casei. Based on sensory acceptability, kulfi with 2 per cent Lactobacillus casei had the highest overall acceptability. Further, blending of kulfi mix with yoghurt was done at 10,20 and 30 per cent levels. On increasing the level of yoghurt blending, all proximate attributes decreased significantly (p≤0.05). Hardness decreased significantly (p≤0.05) on adding oat bran, yoghurt and L.casei. Probiotic kulfi with elaichi flavor had high consumer acceptability. Total solids, pH, first drip time and overall acceptability scores decreased, while acidity and melting rate increased significantly (p≤0.05)with storage at-18±1°C. Based on sensory evaluation, kulfi containing probiotic culture was found acceptable upto 28 days. Probiotic viability decreased on storage, but remained above 106cfu/ml.ThesisItem Restricted Preparation of baby corn soup mix from by-products of an industry(Punjab Agricultural University, Ludhiana, 2018) Vipandeep Singh; Kamaljit KaurThe investigation was undertaken to study the development of technology for baby corn soup mix. Cut pieces of baby corn were generated as waste were procured from Field Fresh Foods Pvt. Ltd. Ladhowal, Ludhiana and were dried at 50±2 °C for 24 hours in try drier. Further, it was grinded to fine powder and sieved and packed in HDPE. Baby corn powder was evaluated for the physico-chemical composition and functional properties. Response surface methodology was used for optimization of corn flour (40-45%), salt (8-12%) and mango powder (10-20%) while, keeping other ingredients like baby corn powder, onion powder, garlic powder, cumin, black pepper, coriander and sugar constant in ratio of 20:2:2:1:1:1:6 for preparation of baby corn soup mix. Further, four formulations were prepared using different level of baby corn powder in ratio of 10:20:30:40 and simultaneously altering corn flour in ratio of 22:32:42:52 while preparing baby corn soup mix. These formulations were analyzed for physico-chemical composition, functional properties, pasting properties, colour and sensory evaluation. Selected formulation was stored in aluminum laminates and stored under ambient conditions. This was analyzed for antioxidant activity, moisture, viscosity, pH, total plate count, water absorption index and sensory score. The significant changes were observed for all the characteristics during storage. The declining trend was observed in antioxidant activity, water absorption index, pH and sensory score of baby corn soup mix during storage and total plate count, moisture and viscosity was found increasing with the increase in period of storage. Among all the four formulations, the formulation containing 20% baby corn powder was selected best on basis of physico-chemical, functional and sensory scores and had shelf life of five months.ThesisItem Open Access Technological evaluation of milk protein powders in low sugar and sugar free baked products(Punjab Agricultural University, Ludhiana, 2018) Karnatak, Kajal; Bajwa, UshaThe investigation was aimed to optimize the formulation of low-sugar and sugar-free baked items (cookies and muffins) incorporating milk protein powders and to study the physico-chemical properties, sensory characteristics and shelf life of these. Sugar was substituted with stevia along with the addition of milk protein powders i.e. skim milk powder (SMP), whey protein concentrate (WPC) and milk protein concentrate (MPC). The quantity of stevia incorporation was equivalent to impart sweetness as of 100 per cent sugar. In low sugar formulations, 25 to 75 per cent and in sugar free formulations 100 per cent of sugar was substituted with stevia powder. Sugar replacement resulted in light brown color, higher spread and reduced hardness in cookies than control. Muffins containing stevia were light brown, lower in volume and more firm than those with added sugar. The overall acceptability of cookies and muffins decreased significantly (p<0.05) with augmented sugar substitution. The incorporation of milk protein powders at a level from 5 to 20 per cent significantly (p<0.05) increased protein and ash content of both the sugar free baked items. There was an improvement in color and reduction in spread and hardness of cookies except for SMP. Milk protein powder incorporation significantly improved volume and browning and reduced firmness of muffins. A level of 10 per cent of SMP, WPC and MPC was found to be optimal for the production of sugar free baked items with superior sensory characteristics. During storage of cookies under ambient conditions, there was a significant increase in moisture content, water activity, free fatty acids and peroxide value and decline in hardness in both HDPE and aluminium laminates. The cookies remained highly acceptable even after 90 days. During storage of muffins, the free fatty acids, peroxide value and firmness got amplified whereas aw and moisture content plummeted. The milk protein powder incorporated muffins in LLDPE packaging had a shelf life of 6 and 9 days under ambient conditions respectively without and with potassium sorbate.ThesisItem Open Access Technological evaluation of roasted chicory root powder as fat replacer in mayonnaise and muffins(Punjab Agricultural University, Ludhiana, 2018) Sukirti; Amarjeet KaurTechnological evaluation of roasted chicory root powder as fat replacer was done in mayonnaise and muffins. Chicory roots were procured, washed, sliced and dried overnight to a temperature of less than 60°C in a cabinet drier. The dried roots were subjected to size reduction in a cyclotech mill and converted into powder. The chicory root powder was analyzed for various properties and was found to be rich in inulin, dietary fiber, total phenols and mineral elements. Roasting of the resultant powder at different temperature and time combinations was done. The L*a*b* values were used to select the best suited powder for mayonnaise and muffins. Mildly roasted powder (130°C/10 mins.) was selected for mayonnaise and severely roasted powder (170°C/ 30 mins.) was selected for muffins. Mayonnaise was prepared by replacing fat with roasted chicory root powder at the levels 0 to 10 per cent. Mayonnaise with 5 per cent replacement of fat with roasted chicory root powder was found to be the best. The selected formulation of mayonnaise was packed in plastic jars and stored at ambient and refrigerated condition till the product became unacceptable so as to study the shelf life of the product. Periodic changes in the free fatty acid content, peroxide value, total acidity, pH, total plate count, viscosity and overall acceptability were recorded. The low fat mayonnaise can be stored upto 60 days with or without preservative under both ambient and refrigerated condition. Similarly, muffins were prepared by replacing fat with roasted chicory root powder at the levels 0 to 30 per cent. Based on the baking, textural and organoleptic evaluation, muffins with 20 per cent replacement of fat with roasted chicory root powder were found to be the best. The selected formulation of muffins were packed in low density polyethylene and stored at ambient and refrigerated condition till the product became unacceptable. Low fat muffins with or without preservative can be stored at ambient condition upto 7 days while under refrigerated condition can be stored upto 35 days. With the replacement of fat with roasted chicory root powder, a net fat reduction of 16.34 per cent and 53.86 per cent was observed in mayonnaise and muffins respectively. Estimated costs for low fat mayonnaise and muffins were 355 Rs/kg and 182 Rs/kg respectively. Economically, both the products were found to be profitable as compared to their respective market counterparts.ThesisItem Open Access Development of functional fermented milk beverage (lassi) incorporating sugarcane juice(Punjab Agricultural University, Ludhiana, 2018) Amrinder Singh; Bajwa, UshaThe present investigation was undertaken with the objective to optimize the formulation and processing conditions of functional lassi sweetened by incorporating sugarcane juice. Milk was transformed into dahi using Lactococcus lactis subspp. cremoris under standard conditions. The level of milk fat content varied from 0 to 4.5 per cent, skim milk powder (SMP) addition from 0 to 3 per cent and sugarcane juice incorporation from 10 to 60 per cent. The optimized magnitude of variables for the preparation of functional lassi was found to be 4.5 per cent fat in milk, 2 per cent skim milk powder (SMP) and 40 per cent sugarcane juice. The lassi samples prepared thereof were packaged in high density polyethylene (HDPE) sachets and glass bottles and stored at room (37oC) and refrigeration (5oC) temperatures. These were evaluated for changes in physico-chemical characteristics, sensory attributes and microbiological quality at regular intervals. There was a decrease in total solids, total sugar, total soluble solids (TSS), pH, ascorbic acid, total phenols and antioxidant activity and increase in acidity and reducing sugars during storage at both temperatures. Standard plate count and lactic count were reduced whereas yeast and mold count got amplified during storage. Lassi remained acceptable and microbiologically safe for 2 and 6 days at room and refrigeration temperature, respectively in both types of packages.ThesisItem Restricted Effect of encapsulated vitamin E on shelf life of cookies(Punjab Agricultural University, Ludhiana, 2017) Jasdeep Singh; Kamaljit KaurThe present study was conducted to evaluate the effect of encapsulated vitamin E on shelf life of cookies. Vitamin E was taken in two forms: synthetic and natural form i.e α-tocopherol and wheat germ oil respectively. Encapsulation parameters were optimized for encapsulation of α-tocopherol using combination of sodium alginate (0.5, 1.0, 1.5 and 2.0 %) as primary wall material and pectin (2.0%) as filler with syringe method of encapsulation. The optimum conditions were selected on the basis of encapsulation efficiency, shape, size, bulk density, yield and swelling index. The encapsulation efficiency of α-tocopherol in microencapsules produced under optimal conditions was 55.6% using sodium alginate 1.5 % w/v and pectin 2.0 % w/v. Encapsules were prepared with enapsulator by using optimized conditions and were compared with the encapsules prepared by syringe method. The results indicated that best encapsulation efficiency was observed in encasules prepared by encapsulator. Similarly wheat germ oil was encapsulated and cookies were prepared by selecting five treatments i.e. WGO-L, WGO-E, E1, E2and E3 and compared with control. Prepared cookies were evaluated for spread ratio, force to rupture and organoleptic parameters. Significant variations were observed for spread ratio and organoleptic parameters. Force to rupture was observed least in WGO-L treated cookies. For shelf life studies, cookies were packed in aluminium laminates, kept under ambient conditions and were analyzed after 15 days interval up to 4 months for moisture content, vitamin E retention, antioxidant activity, free fatty acid, peroxide value, total plate count and overall acceptability. Statistically significant results were found in all the treatments on storage. Moisture content was observed increased with increase in storage period but increase was minor. Vitamin E was observed retained in all treated cookies except WGO-L and was found maximum in E3 treated cookies upto 4 months of storage period. Peroxide value was found nil in treated cookies whereas free fatty acid formation was observed very less in treated cookies as compared to control. Treated cookies showed good antioxidant activity and total plate count was observed least in E3 treated cookies. Overall acceptability showed good acceptance of cookies up to 4 months of storage. The results concluded that encapsulated vitamin E enhances the antioxidant activity and thus shelf life and nutritive value of cookies.ThesisItem Open Access Process Development for Preparation of Toffee from Figs(Punjab Agricultural University, Ludhiana, 2017) Kaul, Shivani; Rehal, JagbirFig is emerging as an important functional food because of its high nutritional and medicinal values. Fig is considered to be an important source of dietary fiber, vitamins and various useful minerals like Iron, Calcium, Magnesium, Copper, etc. Confectionery products due to their sweet taste and flavour are enjoyed worldwide and by all age groups. Fruit toffees contain nutrients like vitamins and minerals present in the original fruit and are nutritionally superior to milk based toffees. The present study was carried out to develop and standardize technology for preparation of fig toffees. Six types of toffee blends were prepared with the replacement of fig in the amount of 0%, 10%, 20%, 30%, 40% and 50%. It was found that toffee containing 30% fig pulp was most desirable and was kept for storage studies. Product was analyzed at an interval of 30 days to assess physico-chemical and organoleptic changes undergoing in the product. It was found that product contained crude fiber content of 2.890 per cent, protein 3.973 per cent, fat 9.877 per cent, phenolic compounds 153.253 GAE mg per 100 g, antioxidants 2460.620 per cent inhibition activity per 100g and flavonoids 15.110 mg per 100 g. Fig toffee was also found to be a good source of minerals like Calcium (235.4 mg per g), Iron (2.945 mg per g), Potassium (356.5 mg per g), Magnesium (41.93 mg per g), Sodium (157.1 mg per g) and Phosphorus (171.3 mg per g). Storage studies revealed that product was stable during three months storage study period.