Faculty Publications

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    Refining of edible oils: A critical appraisal of current and potential technologies
    (Blackwell Publishing Ltd customerservices@oxonblackwellpublishing.com, 2015) Chandrasekar, C.; Charanyaa, S.; Belur, P.D.; Iyyaswami, I.
    Summary: The major sources of dietary lipids are edible oils, which include both vegetable and fish oils. Crude oil extracted from vegetable and fish sources contain mono-, di-, triacylglycerols along with impurities, which necessitates refining. The main objective of refining is to remove the contaminants that adversely affect the quality of oil, thereby reducing the shelf life and consumer acceptance. However, this refining process needs to be tailored as the composition of crude oil is highly variable, depending upon the plant/fish species, geographical location of the source and method of oil extraction. Recently, extensive efforts have been made to develop refining technology, using either conventional physical/chemical processes or several unconventional processes including biological and membrane processes. The first section of this review gives a brief description of general composition of some commonly used vegetable and fish oils, followed by the review of various refining methods and their effects on the oil constituents. Finally, an effort is made to understand the technological gaps in the existing methods and possible directions of research to overcome the said gaps. © 2014 Institute of Food Science and Technology.
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    A new strategy to refine crude Indian sardine oil
    (Japan Oil Chemists Society yukagaku@jocs-office.or.jp, 2017) Charanyaa, S.; Belur, B.D.; Iyyaswami, R.
    Current work aims to develop a refining process for removing phospholipids, free fatty acids (FFA), and metal ions without affecting n-3 polyunsaturated fatty acid (n-3 PUFA) esters present in the crude Indian sardine oil. Sardine oil was subjected to degumming with various acids (orthophosphoric acid, acetic acid, and lactic acid), conventional and membrane assisted deacidification using various solvents (methanol, ethanol, propanol and butanol) and bleaching with bleaching agents (GAC, activated earth and bentonite) and all the process parameters were further optimized. Degumming with 5%(w/w) ortho phosphoric acid, two stage solvent extraction with methanol at 1:1 (w/w) in each stage and bleaching with 3% (w/w) activated charcoal loading, at 80ºC for 10 minutes resulted in the reduction of phospholipid content to 5.66 ppm from 612.66 ppm, FFA to 0.56% from 5.64% with the complete removal of iron and mercury. Under these conditions, the obtained bleached oil showed an enhancement of n-3 PUFA from 16.39% (11.19 Eicosapentaenoic acid (EPA) + 5.20 Docosahexaenoic acid (DHA)) to 17.91% (11.81 EPA + 6.1 DHA). Replacing conventional solvent extraction with membrane deacidification using microporous, hydrophobic polytetrafluoroethylene membrane (PTFE), resulted in a lesser solvent residue (0.25% (w/w)) in the deacidified oil. In view of lack of reports on refining of n-3 PUFA rich marine oils without concomitant loss of n-3 PUFA, this report is significant. © 2017 by Japan Oil Chemists’ Society.
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    Isolation of microcrystalline cellulose from Musa paradisiaca (banana) plant leaves: physicochemical, thermal, morphological, and mechanical characterization for lightweight polymer composite applications
    (Springer Science and Business Media B.V., 2024) Indra Reddy, M.I.; Sethuramalingam, P.; Sahu, R.K.
    Natural cellulose owing to its remarkable microstructural and physiochemical behaviour, and its eco-friendliness have attracted significant interest among the researchers. Therefore, in this work, microcrystalline cellulose (MCC) is extracted from the Musa paradisiaca plant leaf (MPPL) debris which is accumulated in large quantity and treated as waste material. The purified micro-cellulose is obtained by subjecting the MPPL raw material to alkali treatment followed by acid hydrolysis, bleaching and slow pyrolysis. From the FT-IR spectra of the cleaned cellulose, it is observed that its amorphous phase is eliminated. The crystallinity index is found to be 87.42% and this value is attributed to the sodium chlorite bleaching. The particle size analyzer results show that the micro-cellulose found to have a bimodal distribution with an average size of 35.97 μm and standard deviation 16.53. It is evident from SEM that the microcrystalline cellulose is of semi-spherical in shape and found to be aggregated with uneven distribution. Further, TGA analysis is carried out in this work and the results show that the microcrystalline cellulose can exhibit high heat resistance up to 297 °C. Surface roughness values (Ra) for MPPL MCC is 58.41 μm. The properties are well suited for futuristic polymer composite applications such as filler addition in biofilm for packaging industries and coating material in pharma industries. © The Polymer Society, Taipei 2024.