International Research Conference of UWU-2021

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Browsing International Research Conference of UWU-2021 by Author "Abeyrathne, E.D.N.S."

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    Effect of Boomi Tree (Litsea glutinosa) Wax on Internal Quality and Sensory Attributes of Chicken Eggs Stored Under Room Temperature
    (Uva Wellassa University of Sri Lanka, 2021) Rathnayake, H.M.N.C.; Pitawala, H.M.J.C.; Abeyrathne, E.D.N.S.
    Shell eggs having a short shelf life at room temperature. Surface coatings can be used to extend the shelf life and minimize economic losses. Edible mineral oil is used as a coating material but several drawbacks are associated. Waxes are most commonly used hydrophobic film forming materials. Boomi tree (Litsea glutinosa) is found throughout Sri Lanka and its bark mucilage consists of hetero-polysaccharide used in ayurvedic medicine. However, information on boomi tree wax coating on egg quality attributes does not exit. Hence, this study was done to check the effect of boomi tree wax as an external coating material on shelf life, internal quality and sensory attributes of chicken eggs stored under room temperature. Total of 270 freshly laid brown, medium sized, clean eggs were purchased from a layer farm in Demodara. Eggs were individually weighed and coated with boomi wax and mineral oil separately while non-coated eggs were used as the negative control and kept in room temperature. Weight loss, air sac volume, Haugh unit, yolk color, albumen and yolk pH, yolk index, FTIR analysis, Salmonella test and sensory attributes were weekly determined. Albumen and yolk pH were increased. But the increment in the mineral oil coated was significantly lower than the other two (p<0.05). Haugh unit (75.0 to 53.6) and yolk index (0.44 to 0.22) decreased during storage in wax coated and non-coated eggs (p<0.05). Grades of non-coated and boomi wax coated, eggs changed from AA to B within 04 weeks whereas those of mineral oil coated eggs remained in AA. Weight loss of wax coated eggs were significantly higher compared to mineral oil coated eggs (p<0.05). Salmonella sp. were detected in several weeks during storage conditions showing permeability of the microorganisms. FTIR analysis revealed that no chemical changes occurred due to the wax. Increase of air sac was higher in noncoated eggs (5.39±0.3mm) after 42 days compared to wax (4.59±0.2mm) and mineral oil (1.19±0.3mm) coated eggs. In 3 week of storage sensory data was showed significant in sensory parameters. In conclusion, this study showed that Boomi wax is not a suitable coating material for chicken eggs. Keywords: Boomi tree wax; Chicken egg; Haugh unit; Yolk index; Mineral oil
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    Evaluation of Polycyclic Aromatic Hydrocarbons (PAHs) in Smoked Catla (Catla catla) Harvested from Selected Reservoir with Different Combustion Materials and Storage Conditions
    (Uva Wellassa University of Sri Lanka, 2021) Alahakoon, D.A.J.N.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N.S.
    Smoking is one of the oldest techniques of fish preservation and at present smoked fish has higher consumer demand due to their specific taste and aroma which is generated using partial combustion of woods. But, accumulation of carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) through the wood smoke is a major problem associated with smoked fish. Hence, the present study was carried out to evaluate the carcinogenic PAHs levels and their penetration with the storage time in smoked Catla (Catla catla). Freshly harvested Catla fishes (2.5 – 9.7 kg) were (n=3) brought from Handapanagala reservoir, Monaragala and equal size (6 × 5 × 2.5 cm3) fish cubes were smoked in electrical smoker (180 ºF for 1.5 hrs.) using Cinnamon (Cinnamomum verum) and Mahogany (Swietenia macrophylla) wood smoke separately and stored at -20 ºC. Acetonitrile extract of smoked and raw fish samples were treated with a mixture of anhydrous MgSO4: NaCl followed by a mixture of MgSO4: silica propylsulfonic acid cation exchanger to extract and purify PAHs at predetermined time intervals as day 1 and day 7(QuEChERS). Outer layer and center part of the smoked fish were analyzed for sixteen PAHs by Dionex Ultimate 3000 UHPLC system equipped with Hypersil Green PAH column (250 mm x 4.6 mm x 5 μm) and Diode Array detector (254 nm, 1 ml/min, Acetonitrile: water gradient elution) separately and compared with standards. Moisture content and crude fat content of raw fish samples were also analyzed. Indeno[1,2,3-cd]pyrene was detected in one of the raw fish sample, while Benzo[a]pyrene, Benzo[ghi]perylene, Indeno[1,2,3-cd]pyrene were detected in fish samples smoked with Cinnamon wood. Indeno[1,2,3-cd] pyrene was found to be the most abundant PAH and it varies between 198 – 212 μg kg-1. No pattern of penetration of PAHs to center was observed. Detectable amounts of PAHs were not found in any of the samples smoked with Mahogany wood. Therefore, it can be concluded that modern smokers under controlled conditions produce lower levels of PAHs and Mahogany wood could be a suitable wood type to smoke Catla catla. Keywords: Polycyclic aromatic hydrocarbons; Catla; QuEChERS method; Cinnamon; Mahogany
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    Extraction and Purification of Chitin and Chitosan from Portunus pelagicus Crab Shell Waste
    (Uva Wellassa University of Sri Lanka, 2021) Tissera, W.M.J.C.M.; Rathnayake, S.I.; Abeyrathne, E.D.N.S.
    Crab (Portunus pelagicus) shell waste is highly accumulated in Sri Lankan seafood processing factories, but not many efforts have been taken on utilizing it for commercial level chitin and chitosan extraction with a higher percentage purity. Therefore the objective of this study was to modify and develop a scale-up, simple, and high-yielding chemical method for extraction and purification of chitin and chitosan from locally underutilized Portunus pelagicus crab shell waste. A modified process including pre-demineralization (acetic acid), demineralization (citric acid), deproteinization (NaOH), decolourization (n-butanol) deacetylation (NaOH), and purification (EDTA and SDS) was optimized to obtain a new combination of treatments. Pre-demineralization was introduced as a new step when developing the process. Citric acid was found as the best alternative organic acid to replace HCl in demineralization. The final product was characterized by X-Ray Diffraction (XRD) Spectroscopy and Fourier Transform Infrared (FTIR) Spectroscopy and various physicochemical and functional properties were analyzed. Control chitin and chitosan samples were produced using a conventional method for comparison. The yields of crude chitin, crude chitosan, and purified chitosan were 32.52±0.68%, 26.28±0.47%, and 21.78±0.34% respectively whereas in the control chitin and chitosan the yields were 20.34±0.72% and 13.79±0.93% respectively (p<0.05). Percentage purity of the final product on a weight basis was 82.54±1.73% with a degree of deacetylation of 85.84±2.45%. The XRD data revealed that chitosan extracted from the developed methodology is a semi-crystalline compound with two characteristic crystalline peaks at 2θ =9.05° and 19.1° and Crystallinity Index of 67.22%. FTIR analysis revealed that developed chitosan was comparable with control chitosan. Chitosan produced from the developed method showed higher results in physicochemical parameters namely moisture (5.27±0.39%), ash (1.95±0.22%) whiteness index (72.37±0.66%), and functional properties namely water binding capacity (318.74±0.48%), fat binding capacity (351.663±0.69%) DPPH free radical scavenging activity (61.12±0.59%) and ferrous chelating activity (40.19±0.47%) compared with the control (p<0.05). Developed chitosan had no antimicrobial activity for Salmonella and Micrococcus but showed positive antimicrobial activity against locally isolated Escherichia coli at 2.5mg/ml. Thus the developed methodology can be used to obtain high purity and high-quality chitosan with better physicochemical and functional properties from crab shell waste Keywords: Portunus pelagicus; Shell waste; Chitosan; Pre-demineralization; XRD; Percentage purity
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    Functional Properties of Hydrolysates of Bioactive Peptides Extracted from Water Soluble Crude Protein from Hilsa kelee
    (Uva Wellassa University of Sri Lanka, 2021) Meepegamage, L.S.; Abeyrathne, E.D.N.S.
    Hilsa kelee also known as “Karattaya” is a marine pelagic, seasonal fish species which has a high catch during April to September. It is mainly used to produce fish meal and used as baits even though it has high nutrients. In addition, it has a low market value and a demand due to its bony structure leading to high wastage and production of fish protein hydrolysates (FPH) can be an alternative. 20 mg/ml concentrated water-soluble crude protein extractions were mixed with Protease from Bacillus licheniformis (60°C, pH 6.5-8.5), Papain from papaya latex (65°C, pH 5.8- 7.0), α-chymotrypsin from bovine pancreas (50°C, pH 7.8) and Elastase from porcine pancreas (37°C, pH 7.8-8.5) separately in 1:100 (enzyme: substrate) ratios. Each sample was incubated at different time intervals (0, 3, 6, 9, 12 and 24 hr) in predetermined optimum pH and temperatures. Then, 15% SDS-PAGE was used to determine the best hydrolysis condition. Bulk hydrolysates were prepared with Papain-6 h, Protease-3 h, α-chymotrypsin-3 h, Elastase-6 h followed with heat inactivation at 100°C for 15 miutes for further experiments. Then, TBARS assay, Ferrous chelation activity and antibacterial activities by agar well diffusion method was conducted. All treatments were triplicated (n=3). According to the results obtained from TBARS assay, FPHs from papain showed the highest antioxidant properties (5.84±0.05 MDA mg/L) compared to other treatments (p>0.05). Fe (II) chelation activity analysis revealed the FPHs produced from α-chymotrypsin showed the highest chelation (20.81±0.02%) (p<0.05). None of the hydrolysates showed any antimicrobial activities for tested microorganismas up to 20,000 ppm. Thus, FPHs produced using papain for 6 h followed with heat inactivation at 100°C for 15 miutes contain strong antioxidant activity Keywords: Hilsa kelee; Fish Protein Hydrolysates (FPH); Antioxidant; Metal Chelating; Antibacterial activity
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    Production of Bioactive Peptides from Ovotransferrin using Two Enzyme Combinations and Determining the Functional Properties of Its Hydrolysates
    (Uva Wellassa University of Sri Lanka, 2021) Wickramasinghe, H.S.; Ahn, D.U.; Abeyrathne, E.D.N.S.
    Peptides from food sources possess numerous bioactivities which make them useful in improving human health and preventing diseases. Although many studies related to egg protein hydrolysis are availabel, less work has been carried out on the production of bioactive peptides from ovotransferrin using two-step enzyme hydrolysis. Objectives of the research were to produce bioactive peptides from ovotransferrin using two enzyme combinations and to determine the functional properties of its hydrolysates. Lipolyzed ovotransferrin was prepared with 20 mg/mL concentration and treated with protease (3hr at 55oC) (Pro), papain (3hr at 37oC) (Pap), elastase (24hr at 37oC) (Ela), and α- chymotrypsin (3hr at 37oC) (Chy) as the first enzyme treatment. Hydrolysate of first step hydrolysis was treated with the above enzymes in different combinations and incubated for 0-24 hours at the optimal temperatures. 15% SDS - PAGE was used to select the best incubation time for each treatment. Best combinations were used to test for antioxidant, metal chelating, and antimicrobial activities using E. coli and in Total Plate Count. Protease + Papain (ProPap), Protease + α- chymotrypsin (ProChy), α-chymotrypsin + Protease (ChyPro), α-chymotrypsin + Papain (ChyPap), Elastase + α-chymotrypsin (ElaChy), Elastase + Papain (ElaPap), Elastase + Protease (ElaPro) treatments with immediate enzyme addition and heat treatment for 100OC for 15 minutes, Papain + Protease (PapPro), Papain + α-chymotrypsin (PapChy) incubated for 3h followed with heat treatment were selected as the best. Hydrolysates produced with ChyPap treatment showed some level of metal chelating activity (4.11±0.28%) and Ela (-2.88±0.16%), ElaChy (-7.80±0.28%), and ElaPap (- 6.38±0.14) showed metal releasing activities. ChyPap (0.59±0.08 MDA mg/kg) treatment followed by ProChy (0.74±0.07 MDA mg/kg), ProPap (0.78±0.04 MDA mg/kg) and ChyPap treatments showed strongest antioxidant activity than ovotransferrin (0.98±0.07 MDA mg/kg) and hydrolysates produced with single enzyme treatments (p<0.05). However, none of the hydrolysates showed any antimicrobial activities against locally isolated E. coli and in Total Plate Count. Accordingly, hydrolysates produced with two enzyme combination treatments showed strong antioxidant and some metal chelating activities which are important in food processing industries. Keywords: Ovotransferrin, Hydrolysates, Enzyme combination, TBAR