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2018 - 201912020 - 20221
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Author: Navjot Kaur × Start date: 2018 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Extraction of anthocyanins from jamun pomace and their utilization in value added products
    (Punjab Agricultural University, Ludhiana, 2022) Navjot Kaur; A. Sachdev, Poonam
    The present investigation on “Extraction of anthocyanins from jamun pomace and their utilization in value added products” was carried out to utilize jamun pomace, rich in anthocyanins and polyphenols with good antioxidant capacity for the extraction of phytochemicals (total monomeric anthocyanins, total phenols, and flavonoids) using conventional and novel non-conventional techniques, such as ultrasoundassisted extraction, microwave-assisted extraction, enzyme-assisted extraction, supercritical fluid extraction and determining its antioxidant potential using DPPH free radical scavenging activity, ferric reducing antioxidant power, and reducing power assay. The conditions for the extraction of phytochemicals from jamun pomace were optimized using optimization techniques i.e., response surface methodology BBD and CCD design, and Taguchi orthogonal array design. The freeze-dried pomace powder and the pomace extract were further used for the preparation of food and nutraceutical products. The pomace contained good amounts of crude fibre (3.51%), total monomeric anthocyanins (701.72 mg CGE/100 g), total phenols (2779.06 mg GAE/100 g), total flavonoids (1832.83 mg QE/100 g), and DPPH free radical scavenging activity (120.28 µmol TE/100 g). Ultrasound-assisted extraction resulted in the highest anthocyanin yield (637.25 mg CGE/100 g) using optimum conditions of 366.25 W ultrasound power at 37.61 °C temperature for 47.48 min using 70% ethanol acidified with 0.1% HCl. Microwaveassisted extraction yielded maximum of 587 mg CGE/100 g total anthocyanins at microwave power (80%) for 2 min using 1:30 solid-liquid ratio with 0.01% HCl. The qualitative and quantitative analyses using SEM, FTIR, and HPLC, respectively confirmed better extractability of non-conventional techniques as compared to conventional extraction. The freeze-dried pomace powder showed better flowability with 28.57° angle of repose, Carr’s Index (14.95), and Hausner ratio (1.30) with 701.72 mg CGE/100 g anthocyanins. The encapsulation of anthocyanins using spray drying process retained 85.45% of total anthocyanins. The incorporation of freeze-dried powder (5%) with 20 ml ultrasonically extracted pomace extract in paneer spread had 173.33 mg anthocyanins and obtained the highest overall acceptability. The paneer spread retained 92.33% anthocyanins with a shelf life of 16 days at refrigerated (4±1°C) temperature. The butter optimized with 2% encapsulated jamun extract powder had 4.40 mg/100 g anthocyanins with 6 months of shelf life at -18 °C. The pomace tablet providing 16.33 mg anthocyanins with rapid disintegration time (20 min) and release of anthocyanins showed storage stability of 4 months with 75% retention of anthocyanins. The developed products (paneer spread and butter) showed better oxidative and microbiological stability as compared to control products.
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    Development of extruded products from Quality Protein Maize
    (Punjab Agricultural University, Ludhiana, 2018) Navjot Kaur; Baljit Singh
    The 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 (p0.01, p0.05) 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.