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Author: Navjot Kaur × End date: 2022 × Start date: 2020 ×
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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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    ThesisItemOpen Access
    Production of probiotic Aloe vera juice
    (Punjab Agricultural University, Ludhiana, 2021) Navjot Kaur; Katyal, Priya
    Aloe Vera juice is rich in vitamins, minerals, fibers, nutrients, anthraquinones, saponins, phytosterols and salicylic acid. Its composition proves it to be an excellent source of prebiotics and a potential substrate for probiotics. Though Aloe Vera juice has been used for its medicinal and health benefits since ages, its value addition by converting it into a synbiotic is lesser exploited so far. This investigation involves physicochemical, microbiological, antioxidant and sensory evaluation of probiotic Aloe vera juice developed at the lab scale by using Lactobacillus acidophilus MTCC 10307. The probiotic culture was inoculated to the Aloe vera juice with initial concentration of 109-1010 CFU/ml. The probiotic viability, pH, total soluble solids (TSS), titrable acidity, total sugars, reducing sugars, non-reducing sugars, lactic acid content, anti-oxidant activity, vitamin C and microbial contaminations were measured at weekly interval upto six weeks. The probiotic viability remained above 8 log CFU/ml during the first four weeks of storage at 4°C. The total plate count, coliform count and yeast and mould count also remained within satisfactory limits. The developed probiotic aloe vera juice was exposed to sensory analysis by a panel of five semi trained judges on the basis of nine-point hedonic scale. Statistical analysis showed a significant difference in taste, texture, aroma, mouth feel of the aloe vera juice and probiotic aloe vera juice, with nonsignificant difference in appearance, color and overall acceptability at 5% level of significance. Though taste of probiotic aloe vera juice scored less but difference in overall acceptability was non-significant. The sensory evaluation of aloe vera juice with and without probiotic inoculation revealed it to be potential synbiotic product.