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ThesisItem Open Access Development of instant maize porridge using extrusion technology(Punjab Agricultural University, Ludhiana, 2016) Sidhu, Arshpreet Kaur; Baljit SinghA study was carried out to develop instant maize porridge using a co-rotating intermeshing twin screw extruder. Maize variety PMH1 was ground into flour and extruded. Response surface methodology (RSM) was used to study the effects of feed moisture content, screw speed and barrel temperature on response variables. Central Composite Rotatable Design (CCRD) with moisture (12-16 %), screw speed (300-500 rpm) and temperature (120-180oC) as independent variables produced 20 different combinations. Each of these combinations were used to investigate the effect of these variables on specific mechanical energy (SME), bulk density (BD), water absorption index (WAI), water solubility index (WSI) , colour (L*, a*, b*) and overall acceptability. The response 3D graphs were plotted as a function of two variables to show the effect of process variables on the physical and functional properties of the developed instant maize porridge. An optimization of the process variables was attempted for maximum desirability. Numerical and graphical optimization techniques were used to get the optimized conditions. The optimized conditions for preparation of instant maize porridge were 14.5% moisture, 345.6 rpm screw speed and 170.9oC temperature. Storage studies were conducted for 4 months and the parameters analysed were moisture, water activity, free fatty acids and overall acceptability. It was concluded that the developed instant maize porridge could be stored in low density polyethylene bags at ambient conditions with maximum retention of organoleptic quality.ThesisItem Restricted DEVELOPMENT OF INSTANT KHEER MIX USING EXTRUSION TECHNOLOGY(2013) simta singlaExtrusion technology was used to optimize the process for preparation of precooked rice granules for making instant kheer mix. Kheer is a traditional Indian dessert made from milk, sugar and rice. It generally takes long time for cooking. With this study, process to render this product instant was optimized. Effect of moisture (16-20%), screw speed (100-300rpm) and temperature (130-170⁰C) on bulk density (BD), Water Absorption Index (WAI), Water Solubility Index (WSI) and starch conversion (SC) was studied. BD, WAI and SC increased with increasing moisture. Increase in screw speed and temperature resulted in decrease in BD and increase in WAI, WSI and SC. Interactions of any two independent variables were also studied for any significant effect on any of the dependent variables. Interaction of feed moisture and screw speed was found to significantly affect BD and WAI in a positive manner. Process was optimized for minimum BD and maximum WSI and SC. The most suitable working conditions were found to be 17.7% moisture, 285-300 rpm screw speed and 170⁰C temperature. Further ratio of extrudate, Skimmed Milk powder (SMP) and sugar was standardized. The final mix contained extrudate, SMP and sugar in ratio 45:35:20, reconstitution was done in standardized milk at 80⁰C, with mix to milk ratio of 1:3. Storage studies were conducted for a period of three months. During the storage period, the mix was analyzed for its moisture content and overall acceptability at monthly intervals. Moisture showed slight increase by end of third month. Overall acceptability on the basis of sensory evaluation decreased slightly during storage but remained within acceptable range.ThesisItem Restricted UTILIZATION OF SPICES AND HERBS FOR IMPROVEMENT OF QUALITY AND SHELF LIFE OF BAKERY PRODUCTS(PAU Ludhiana, 2011) Gurpreet Kaur Dhillon; Amarjeet KaurPresent study was aimed to minimize the use of chemical preservatives by replacing them wholly or partially with natural preservatives i.e. spices and herbs in bakery products, without altering the desired quality attributes. Powdered spices and herbs were evaluated for antioxidant activity and total phenolic content. The inhibitory effects of spices and herbs on Aspergillus, Eurotium and Penicillium were evaluated in vitro using PDA (potato dextrose agar) media. Incorporation of spices and herbs modified the farinographic curve characteristic and pasting properties of the dough. Quality and shelf life of bakery products i.e. bread and muffins by incorporating spices and herbs (cinnamon, clove, garlic, oregano and thyme) in bread and muffins at (1, 2, 3 and 4 % level) alone or in combinations were studied. Based on the bread and muffins making and organoleptic quality the level of incorporation of spices and herbs to be used in the standard recipe were selected. Bread with acceptable product quality and organoleptic properties were prepared after incorporation of spices and herbs (2 % cinnamon, 1 % clove, 1 % garlic, 2 % oregano and 2 % thyme) and their combinations i.e. cinnamon : oregano – 2:2, cinnamon : thyme – 2:2, clove : oregano – 1:2. Muffins were made after incorporation of spices and herbs (2 % cinnamon, 1 % clove, 2 % oregano and 2 % thyme) and their combinations were for cinnamon:clove – 2:1, cinnamon : thyme – 2:2 and oregano: thyme – 2:2 with very good product quality and organoleptic properties. Bread prepared after incorporation of best combination of spices and herbs were packed in LDPE and PP and stored under ambient and refrigerated condition for 10 days to study the shelf life of product by estimating periodic changes in moisture content, water activity, free fatty acid, peroxide value, pH, texture and visual mold growth. Spiced bread had a shelf life of 8 and 10 days at ambient and refrigerated temperature, respectively. Similarly, muffins prepared from flour supplemented with best combination of spices and herbs and were packed in LLDPE and stored under ambient and refrigerated conditions for one month to find out shelf life of the product. Muffins prepared from spices and herbs remained acceptable till 28 days at ambient condition and 35 days when stored under refrigerated condition. Combinations of best levels of spices and herbs along with 0.1 per cent calcium propionate or potassium sorbate enhanced the shelf life of bread from 3-4 days to 10-12 days and of muffins from 14 days to 35 days at room temperature.ThesisItem Restricted DEVELOPMENT OF VARIETY BAKED PRODUCTS INCORPORATING CEREAL BRAN(PAU Ludhiana, 2011) Bhupinder Jit Kaur; Savita SharmaNow a days, consumers have been looking for food ingredients that are natural and healthy. Baked products are considered as an excellent vehicle for fortification, value addition and feeding at mass scale. Keeping in view the above factors there was a need to develop and standardize the technology for bakery products (buns, pizza base and flat bread) using fibre as enrichment source. Therefore, cereal brans have been identified as fortificant. This will also improve the functionality of cereal bran for potential utilization. The addition of increasing levels of fibre in a long way improves the health status of vast majority of health conscious population who are the main target of this technology. The effect of blending of wheat flour with wheat bran, oat bran and rice bran, singly and in combination (0-15%) on the physiochemical, rheological, baking characteristics were examined. Protein and dietary content of wheat flour increased with addition of bran. Pasting properties of wheat flour were significantly affected with addition of bran in blends. Significant variations were assessed in the farinographic properties of flour bran blends. High percentage of water absorption was noticed at 15 percent level of bran, while mixing tolerance index decreased at this level. Quality products (buns, pizza base, flat bread) were prepared with incorporation of cereal bran up to 0-15 percent. Maximum loaf weight was observed at 15 percent bran enrichment of product, where as loaf volume decreased at higher percentage of bran in products. L* and a* values of baked products significantly affected at higher level of bran supplementation. Supplementation of fibre sources has significant effect on the texture of baked products. Recommended level of wheat bran and oat bran is 10 percent and rice bran and bran in combination is 5 percent for all the production of value added baked products. Overall the quality of fibre enriched buns, pizza base and flat bread were at acceptable level, which was reflected from mass consumer acceptability. Keywords: Cereal brans, baked products, sensory quality, texture, colour, visual assessmentThesisItem Open Access BAKING AND SENSORY QUALITY OF WHOLE WHEAT AND FLAXSEED BASED COOKIES AND MUFFINS(PAU Ludhiana, 2011) Ramneet Kaur; Amarjeet KaurPresent study was conducted to develop convenient functional foods i.e. cookies and muffins after incorporating flaxseed meal which is gaining significance as dietary supplement due to its proven multitudinous effects on human health. Germination of flaxseed was done to further enhance its health benefits. Different blends were made by incorporation of ungerminated and germinated flaxseed meal in wheat flour and whole wheat meal and it was found that both ungerminated and germinated flaxseed meal increased the dough development time and water absorption. Paste temperature also increased in both wheat flour and whole wheat meal. Ground ungerminated and germinated flaxseed meals were incorporated at levels 5, 10, 15 and 20 percent in cookies. Spread ratio of cookies increased with addition of both ungerminated and germinated flaxseed meal, more so for germinated flaxseed meal. Whole wheat meal cookies had better acceptability as compared to wheat flour based cookies. With the addition of flaxseed, protein, fiber, fat, ash and calorific value increased. Based on baking, textural and sensory properties, the incorporation of 15 percent level of ungerminated and germinated flaxseed meal was found best for cookie making. Wheat flour and whole wheat meal cookies prepared after incorporation of best levels of flaxseeds were packed in Aluminium Laminates and stored under ambient conditions for 4 months and assessed periodically for changes in moisture, free fatty acid, peroxide value and microbial load. Flaxseeds cookies stored well for 3 months with acceptable flavor and texture. Similarly, wheat flour and whole wheat meal muffins were prepared after addition of ungerminated and germinated flaxseed meal at levels 5, 10, 15, 20, 25 and 30 percent. With the addition of flaxseed, there was increase in specific volume of muffins and improvement in texture. On the basis of sensory scores and textural properties, the best level of flaxseed meal selected were 15 percent for ungerminated and 10 percent for germinated. Muffins prepared from the best levels were packed in LLDPE and stored under ambient and refrigerated conditions for 1 month to assess the shelf life. Muffins stored well for 15 days under ambient conditions and for 1 month under refrigerated conditions.ThesisItem Open Access DEVELOPMENT OF EXTRUDED SNACKS UTILIZING BROKEN RICE AND MUNG BEAN(PAU Ludhiana, 2012) Chetan Sharma; Baljit SinghA study was carried out to develop extruded snacks from broken rice (70 parts) and mung bean (30 parts) using twin screw intermeshing extruder. Response surface methodology (RSM) was used to study the effects of feed moisture content, screw speed and barrel temperature on response variables. Central Composite Rotatable Design (CCRD) with moisture (14-18%), screw speed (400-550 rpm) and die temperature (130-170 °C) as independent variables produced 20 different combinations that were used to investigate the effect of these variables on specific mechanical energy (SME), bulk density (BD), water absorption index (WAI), water solubility index (WSI), and hardness. The response contour plots were plotted as a function of two variables to show the effect of process variables on the physical and functional properties of the extruded snacks. Significant regression models were established with the coefficient of correlation (R2) greater than 0.95. An optimization of process variables was attempted for maximum desirability. Increasing feed moisture caused increase in density and hardness whereas lowers SME, WAI and WSI. Increasing screw speed resulted in increase in SME and WSI and decrease in WAI of the extrudates. Higher barrel temperature reduced SME, density and hardness but increased the WSI of the extrudates. Optimized conditions for preparation of snacks were 14% moisture, 549 rpm screw speed, 148° C. the moisture, protein, fat, fiber, ash and carbohydrates content of snacks were 5.9, 12.7, 0.6, 2.5, 2.9 and 75.1 per cent respectively.ThesisItem Open Access EFFECT OF PROCESSING ON THE REDUCTION OF ENDOSULFAN RESIDUES IN OKRA (Abelmoschus esculentus L.)(PAU Ludhiana, 2011) Shelke Anil Ramesh; P. S., RanoteThe study was carried out to check the effect of processing and storage on the reduction of endosulfan residues, physico-chemical composition and quality of fresh, canned and dehydrated okra fruits. The moisture, pH, TSS, ascorbic acid, protein, pectin, crude fibre and chlorophyll content of fresh okra fruits was 89.65 per cent, 6.79, 16.00 oBrix, 21.82 mg/100g, 1.99 per cent, 0.30 per cent, 3.75 per cent and 75.97 mg/100g, respectively. Moisture, pH, TSS, ascorbic acid, pectin, crude fibre and chlorophyll content of canned okra decreased by 2.08, 1.62, 38.88, 47.50, 21.25, 52.06 and 53.65 per cent, while protein increased by 29.79 per cent during 6 months of storage at ambient conditions. The moisture content and pH of dehydrated okra increased by 3.07 and 0.90 per cent, respectively whereas TSS, ascorbic acid, protein, pectin, crude fibre and chlorophyll content decreased by 39.58, 56.44, 3.18, 28.62, 19.58 and 26.38 per cent, respectively during 6 months of storage packed in HDPE bags stored under ambient conditions. The endosulfan was applied @ 3.5mL litre-1 on samples of okra through simulated trial in laboratory. The processing treatments reduced the endosulfan residues from okra fruits. Washing (2 min), washing + blanching (3 min), washing + trimming + blanching and washing + trimming + blanching + KMS treatment resulted 39.22, 61.00, 66.95 and 73.54 per cent endosulfan residues reduction from okra fruits, respectively. Reduction in endosulfan residue was recorded as 87.07, 92.38, 97.97 and 99.09 per cent in canned okra when analysed at 0, 15, 45 and 60 days, respectively. The residues of endosulfan in canned okra went below the MRL (maximum residue limit) of 2 mg kg-1 after 15 days of storage. Reduction of 24.69 per cent in endosulfan residues was recorded in dehydrated okra and further reduction by 63.08 per cent was recorded when dried okra was rehydrated. However, 32.82, 35.92 and 42.10 per cent reduction was noted when analysed at 15, 45 and 60 days intervals in dehydrated okra packed in HDPE (high density polyethylene) bags. The studies clearly indicated that pretreatments and processing had marked effect upon reduction of endosulfan residues in okra.ThesisItem Open Access Development of chicken meat patties incorporating natural antioxidants(PAU Ludhiana, 2011) Abhishek Kashyap; S.S., ThindThe objective of this study was to evaluate the quality and shelf life of chicken meat patties by incorporating natural plant antioxidants like ginger paste, tomato paste and aloe vera gel at optimized levels. Ginger paste (0, 2.0, 4.0, 5.0, 6.0, 8.0 and 10.0% levels), tomato paste (0, 1.0 and 2.0 up to 5.0% levels) and aloe vera gel (0, 1.0, 2.0 up to 5.0 % levels) were incorporated in the chicken meat patties for the standardization of recipe. On the basis of sensory evaluation, the best levels of ginger paste (5%), aloe vera gel (3%) and tomato paste (4%) were incorporated in the chicken meat patties which were kept frozen (-20±ºC) for two months, after packing in LDPE and HDPE (vacuum packs), to study the shelf-life of the product. It was observed that AGT chicken meat patties had significantly (p≤0.05) higher moisture, ash, cooking yield, sensory attributes, lower protein, fat, free fatty acid content, peroxide value, lower reduction in diameter and shear force in comparison to control samples. Non significant changes (p≤0.05) in pH and total viable count (TVC) were observed. The chicken meat patties containing natural antioxidants had significantly (p≤0.05) higher acceptability than control chicken meat patties. HDPE (Vacuum packed) chicken meat patties had significantly (p≤0.05) higher moisture, lower free fatty acid content, lower peroxide value and higher scores for overall acceptability than LDPE packed chicken meat patties at the end of two months of frozen storage period (-202C).ThesisItem Open Access ANTIOXIDANT PROPERTIES OF CEREAL BRANS AND THEIR POTENTIAL FOOD APPLICATIONS(PAU Ludhiana, 2011) Basharat Nabi Dar; Savita SharmaThe present investigation was carried out to evaluate the antioxidant and food potentials of cereal brans (wheat, rice and oat) singly and in combination. Conventional and microwave assisted solvent extractions were applied to quantify the antioxidants in cereal brans. Conventional solvent extraction (50, 60 and 700C) and microwave assisted solvent extraction (2450 MHz for 2, 3.5 and 5 min) were performed using acetone, hexane and methanol as solvents. Total phenolic assay, DPPH (2, 2-diphenyl-1-picrylhydrazyl) and TEAC (trolox equivalent antioxidant capacity) were assessed for antioxidant capacity. Highest antioxidant capacity was obtained at 60oC for conventional solvent extraction and 3.5 min for microwave extraction. Among various solvents used methanolic extracts acquired maximum scavenging capacity under both types of extractions. The microwave assisted solvent extraction demonstrated higher results for antioxidants compared to conventional solvent extraction. Rice bran had maximum total phenolic content (mg GAE/g) and percent inhibition of DPPH radical under both types of extraction conditions. Wheat bran displayed highest TEAC in conventional as well as in microwave assisted extraction conditions followed by bran in combination and oat bran. Cereal brans singly and in combination were blended at varying levels for extruded snacks (10, 20 and 30%), breakfast cereal-Porridge (5, 10 and 15%) and chapatti (5 and 10%). Enriched products were assessed for antioxidant assay and quality. The antioxidant activity of bran supplemented products was higher than control. Antioxidant capacity and total phenolics increased significantly with increase in bran level supplementation in resultant product. On the basis of quality assessment, 20% enrichment level for extruded snacks and 10% level for breakfast cereal-Porridge and chapatti was best. Antioxidant activity and product quality was assessed during storage for six months at one month interval. Moisture content, water activity and free fatty acids remained stable during entire storage period. A slight reduction in antioxidant capacity of cereal bran enriched products was noticed with prolonged storage. Antioxidant capacity of cereal brans has positive effect on extending shelf life of cereal bran enriched products. Enriched products were highly acceptable upto 6 months of storage.