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ThesisItem Restricted Development of extruded products from Quality Protein Maize(Punjab Agricultural University, Ludhiana, 2018) Navjot Kaur; Baljit SinghThe present research work was carried out to explore the utilization of quality protein maize (QPM) for development of extruded products (Snacks and instant porridge). The effect of extraction methods (Reflux and Stirring) as well as solvent concentrations on antioxidant activity of normal and quality protein maize was also evaluated. Central composite rotatable design (CCRD) in response surface methodology (RSM) was used to design experiments and to study the effect of independent variables on dependent variables. Significance of fitted model (p0.01, p0.05) was described based on ANOVA. The effect of three independent variables (moisture content (14-18 %), barrel temperature (125-175 °C) and screw speed (400-550 rpm)) on dependent variables such as carbohydrate solubility (CS), protein solubility (PS), hydration power (HP), milk absorption capacity (MAC), water absorption index (WAI), water solubility index (WSI), bulk density (BD) etc. was evaluated. Multiple regression equations were obtained to describe the effects of each variable on product responses. Feed moisture and barrel temperature exhibited significant effect on PS, HP and MAC While screw speed showed non significant affects on HP and CS of porridge. Among the processing parameters, screw speed demonstrated a significantly higher effect on the product responses of extruded snacks. The optimum extrusion conditions to prepare QPM based porridge and snacks were feed moisture 15%;14.66%, barrel temperature 137.50º C; 171.96º C and 480.50 rpm ; 485.92 rpm screw speed , respectively. The final product were stored for 6 months and found to be acceptable at end of 6 months. So, Quality protein maize can be extruded into an acceptable as well as nutritious breakfast food and can provide wide opportunity to the food industry.ThesisItem Open Access Functionality and stability assessment of fruit based dairy beverage(PAU, 2015) Shukla, Preeti; Bajwa, UshaThe present investigation was carried out to enhance the functional properties of mango based milk beverage through the generation of Maillard reaction products (MRPs) and assess its storage stability. Response Surface Methodology (RSM) was applied to optimize the level of milk fat, sugar and mango pulp in the beverage for responses of desirable viscosity, maximum antioxidant activity and high overall acceptability. The optimized levels were found to be 0.5 per cent milk fat, 6.0 per cent sugar and 30.0 per cent mango pulp. The beverage was packaged in HDPE sachets and glass bottles, sealed, pasteurized at 80°C for 5 sec and stored at 5.0°C. Also, the beverage was packaged in glass bottles, sterilized at 116°C for 15 min and stored at ambient temperature (25°C). The samples of beverages were evaluated for physicochemical, microbial and sensory quality at regular intervals. There was a significant (p<0.05) decrease in total solids, pH, ascorbic acid, reducing sugars, viscosity, antioxidant activity, HMF concentration and sensory scores and increase in total soluble solids and acidity during storage. Standard Plate Count (SPC) and Yeast and mold count of pasteurized beverages increased significantly (p<0.05) after ten days whereas sterilized beverage remained microbiologically stable even after 75 days of storage. The pasteurized beverage was acceptable up to six days whereas the sterilized one upto 60 days. To explore the role of milk proteins and sugar in MRP generation, simulated beverage samples were formulated using whey protein, casein and sugar in the concentration range from 0.0 to 1.0, 0.0 to 1.0 and 0.0 to 6.0 per cent, respectively. These were subjected to heat treatments varying from 63 to 121°C for 15s to 50 min. Antioxidant activity (as % inhibition of DPPH) and HMF as an index of MRPs generation, were determined at regular time interval during heat treatment. There was a significant (p<0.05) increase in the antioxidant activity and HMF concentration of samples at all the thermal treatments. The samples containing higher amounts of milk protein and sugar produced more MRPs and exhibited more antioxidant activity than control. The incorporation of mango further contributed to antioxidative components and enhanced the functional quality of the milk beverage.ThesisItem Open Access Development of instant weaning foods based on maize-pulses by using extrusion technology(Punjab Agricultural University, Ludhiana, 2016) Ali, Salim Abdelmonem AbdelhaleemThe aim of this study was to develop instant weaning mixes from locally-available and low-cost ingredients using twin-screw extruder and to assess their nutritional quality and storage stability. Weaning mixes were processed using extrudates of maize (Zea mays), mungbean (Vigna radiata) and chickpea (Cicer arietinum). The proportion of flour blends prepared for extrusion process was maize + mungbean in the ratio of 70:30 and maize + chickpea in the ratio of 80:20. Experiments were designed using response surface methodology (RSM) with three independent variables [feed moisture (14–18 %), screw speed (400–550 rpm) and barrel temperature (125–175°C)] and five dependent variables (specific mechanical energy, bulk density, water absorption index, water solubility index and degree of gelatinisation) at five levels of central composite rotatable design (CCRD). Optimised extrusion conditions were 14.33% feed moisture, 524 rpm screw speed and 174°C barrel temperature for maize-mungbean extrudates; and 14.13% feed moisture, 534 rpm screw speed and 167oC barrel temperature for maize-chickpea extrudates. Extrudates were ground and mixed with skim milk powder and sugar to prepare the final weaning mixes which were stored for six months at room temperature. Four optimised weaning mixes were prepared by mixing ground extrudates (maize–mungbean or maize-chickpea), skim milk powder and sugar at different levels. The quality attributes (functional properties, nutritional quality and in vitro digestibility) were evaluated. Storage stability parameters [moisture content, free fatty acids, colour attributes (L*, a*, b*) and sensory evaluation] were investigated during storage. All weaning mixes were acceptable for a period of six months. Weaning mixes were similar to the commercially available products in terms of quality attributes and had considerably less cost. The nutrient content of the weaning mixes was in accordance with the standards specified by PFA, (2004) with high protein and starch digestibility. Such mixes with low cost, high nutritional value and high storage stability can be used to overcome the malnutrition among children in developing countries.ThesisItem Open Access Development of instant weaning foods based on maize-pulses by using extrusion technology(Punjab Agricultural University, Ludhiana, 2016) Ali, Salim Abdelmonem Abdelhaleem; Baljit SinghThe aim of this study was to develop instant weaning mixes from locally-available and low-cost ingredients using twin-screw extruder and to assess their nutritional quality and storage stability. Weaning mixes were processed using extrudates of maize (Zea mays), mungbean (Vigna radiata) and chickpea (Cicer arietinum). The proportion of flour blends prepared for extrusion process was maize + mungbean in the ratio of 70:30 and maize + chickpea in the ratio of 80:20. Experiments were designed using response surface methodology (RSM) with three independent variables [feed moisture (14–18 %), screw speed (400–550 rpm) and barrel temperature (125–175°C)] and five dependent variables (specific mechanical energy, bulk density, water absorption index, water solubility index and degree of gelatinisation) at five levels of central composite rotatable design (CCRD). Optimised extrusion conditions were 14.33% feed moisture, 524 rpm screw speed and 174°C barrel temperature for maize-mungbean extrudates; and 14.13% feed moisture, 534 rpm screw speed and 167oC barrel temperature for maize-chickpea extrudates. Extrudates were ground and mixed with skim milk powder and sugar to prepare the final weaning mixes which were stored for six months at room temperature. Four optimised weaning mixes were prepared by mixing ground extrudates (maize–mungbean or maize-chickpea), skim milk powder and sugar at different levels. The quality attributes (functional properties, nutritional quality and in vitro digestibility) were evaluated. Storage stability parameters [moisture content, free fatty acids, colour attributes (L*, a*, b*) and sensory evaluation] were investigated during storage. All weaning mixes were acceptable for a period of six months. Weaning mixes were similar to the commercially available products in terms of quality attributes and had considerably less cost. The nutrient content of the weaning mixes was in accordance with the standards specified by PFA, (2004) with high protein and starch digestibility. Such mixes with low cost, high nutritional value and high storage stability can be used to overcome the malnutrition among children in developing countries.ThesisItem Open Access Optimization of Process Parameters for Extrusion, Frying, Packaging and Storage of Snack Food using Agro Processing Byproducts(Punjab Agricultural University, Ludhiana, 2016) Raleng, Angam; Amarjit SinghABSTRACT This study aimed at optimization and development of pineapple pomace powder, pulse flour and rice flour-based snack using response surface methodology (RSM). Experimental design with barrel temperature (120-180°C), feed moisture (14-18%) with pineapple pomace level in the range of (6-20%) as independent variables produce 20 different combinations that were studied using RSM to investigate the effect of these three variables on product responses (Bulk density, expansion ratio, hardness, water absorption and solubility indices). The product responses were mostly affected by changes in moisture content and barrel temperature rather than the pineapple pomace level. Increasing the moisture content and barrel temperature caused the increase in expansion ratio and water solubility index (WSI) but decrease in specific mechanical energy (SME), hardness, density and WSI of the extruded snacks. Water absorbency index (WAI) and expansion ratio are mostly affected by the level of pineapple pomace. The WAI and expansion ratio decreased with increase in the pineapple pomace level. The optimized extrusion parameters for preparation of snacks were 14.94% moisture, 180°C temperature and 6% pineapple pomace powder. The extrudates developed under optimized conditions contains 5.27 % of moisture wb, 4.96 % of protein, 3.05 % of fibre, 2.18 % of ash and colour L-value of 66.18, a-value of 1.91, b-value of 16.71. The Frying time and temperature significantly affect the functional and structural properties of the extrudates. With increase in frying temperature and time caused decreased in hardness, colour L and b values but increase in colour a values and also overall acceptability of extrudates was also observed with changing frying temperature and time. The product was preferred at a frying temperature of 180°C and for a time of 15s. The packaging materials significantly affect the responses of the fried extrudates. With storage period free fatty acid, hardness, peroxide value, moisture content, colour a-values and overall change in colour (ΔE) increases but colour L and b values decreases. The quantitative variation in quality attributes suggests that the products packed in aluminium laminated pouch could be stored for 4 months duration without any deteriorationThesisItem Open Access Development of technologies for enhancing the utilization of guar bean (Cyamopsis tetragonoloba) in grain based foods(Punjab Agricultural University, Ludhiana, 2016) Sharma, Priyanka; Amarjeet KaurIndia accounts for highest guar production in world which is mostly used for fodder and gum extraction. Its utilization in food purposes needs to be explored because of the health benefits offered due to its high galactomannan, protein and fibre content. Therefore, present work was carried out to study the guar flour characteristics and develop technologies to enhance its utilization in grain based foods. Three guar varieties i.e. G 80, Ageta 112 and HG 365 were assessed for physico-chemical, milling, thermal, rheological and functional properties. Gums were extracted from guar seeds and its proximate analysis was carried. Protein fractionation of guar seeds revealed globulins to be the largest proportion of protein present. Guar seeds were treated with different methods i.e. dehusking (roasting for 2 min, dehusking), soaking (27-30 ºC, 18 hours), autoclaving (110 ºC for 10 min, 120 psi), extrusion (Clextral, Twin screw extruder) and germination (soaking at 30±5ºC, germination for 3 days), dried at 45 ºC and milled to flour. The effects of processing treatments on proximate composition, colour, antinutritional factors (i.e. tannins, polyphenols and phytic acid) were assessed. Autoclaving was selected as best treatment for incorporation into food products on the basis of its effectiveness in reducing antinutritional factors. Grain based products with incorporation of autoclaved guar flour i.e. muffins (at 5, 10, 15, 20 %), cookies (at 1, 2, 3, 4, 5 %) and RTE extruded snacks (at 5, 10, 15, 20 and 25 %) were prepared and best levels from each variety were selected for all the products on basis of sensory acceptability. The selected levels of autoclaved guar flour incorporated muffins (i.e. 10, 15 and 5 % of G 80, Ageta 112 and HG 365, respectively), packed in LLDPE were assessed for quality, sensorial and shelf life (under ambient and refrigerated conditions) studies. Similarly, selected best levels of autoclaved guar flour incorporated cookies (3, 3 and 2 % of G 80, Ageta 112 and HG 365, respectively) and autoclaved guar flour incorporated RTE extruded snacks (i.e. 10 % G 80, 15 % Ageta 112 and 5 % HG 365) were assessed for quality, sensorial and shelf life (packaged in aluminum laminates and HDPE packages) studies. Based on the results, it was concluded that Ageta 112 variety was most acceptable for food product preparation. This variety was recommended for muffin and extruded snacks preparation upto 15% incorporation level on basis of its nutritional, functional and sensory properties.ThesisItem Open Access Development and Assessment of Functional Properties of HTST Processed Pregelatinized Pasta(Punjab Agricultural University, 2016) Rafiq, Aasima; Sharma, SavitaThe present investigation was undertaken to explore the potentiality of twin screw extruder for development and assessment of functional properties of High Temperature Short Time processed pregelatinized pasta. Semolina and brown rice (singly or in combination with legume) and different multigrain blends were used for preparation of pregelatinized pasta. General factorial design was used for generating experimental runs for semolina and multigrain pasta. For brown rice and cereal-legume pasta response surface methodology was used for optimization of the extrusion processing conditions and regression analysis was carried out to fit mathematical models to the experimental data. Feed moisture (28-36%), barrel temperature (60-110°C), screw speed (100-200rpm), legume level (10-30%) and different multigrain blend composition were chosen as the independent variables while degree of starch gelatinization, cooking quality (minimum cooking time, water absorption, volume expansion and gruel solid loss), amylose leaching and swelling power were the product responses. Different raw materials were subjected to extrusion by co-rotating twin screw extruder at varying processing conditions as per the experimental design. Functional properties of HTST processed pregelatinized pasta were significantly affected by the processing conditions. Degree of starch gelatinization (DSG) by amylose-iodine method revealed that feed moisture and barrel temperature showed a positive correlation with degree of starch gelatinization whereas increased legume level depicted an inverse effect. Overall, higher screw speed and feed moisture exhibited dominant effect on the cooking quality of pregelatinized pasta (semolina, brown rice, legume supplemented and multigrain pasta). Luminosity, redness and yellowness increased with increasing feed moisture. Pasting properties revealed lower peak and final viscosity with increased barrel temperature. Firmness of cooked pasta elevated with an increase in the barrel temperature and feed moisture. The samples processed at higher feed moisture and lower barrel temperature depicted higher retention of total phenolics and flavonoid content. Increase in antioxidant activity of pasta was noticed at higher feed moisture and lower barrel temperature. Extrusion processing was found to improve the in vitro starch and protein digestibility of pregelatinized pasta prepared from various cereals (singly or in combination with legumes). Pregelatinized pasta undergo extensive gelatinization as inferred from differential scanning calorimetry. The scanning electron microscopy images displayed varying patterns indicating polymer leaching, starch degradation and void air cells in the pregelatinized pasta. Irrespective of raw material, dynamic viscoelasticity analysis of pasta revealed that storage modulus (G´) was found much higher than loss modulus (G´´) indicating more elastic behaviour. The pregelatinized pasta packed in High density polyethylene and stored at ambient storage conditions were found acceptable up to 5 months storage period. The pregelatinized pasta products prepared at optimized processing conditions viz. feed moisture (31-32% for semolina and brown rice pasta, 32-36% for legume supplemented pasta and 34% for multigrain pasta), barrel temperature (90°C) and screw speed (200rpm) exhibited most desirable functional, cooking, sensory characteristics and mass acceptability.
