@article{jfnr20219104,
author={{Nawaz, Haq and Jabeen, Raheela and Mehmood, Rana Farhat and Irshad, Misbah and Irfan, Muhammad Imran and Shahid, Madiha and Nawaz, Mubashir},
title={Effect of Freeze-Thaw Treatment on<i> </i>Free Radical Scavenging and Linoleic Acid Reducing Potential of <i>Nelumbo nucifera </i>Rhizome Starch: Response-surface Optimization},
journal={Journal of Food and Nutrition Research},
volume={9},
number={10},
pages={523--530},
year={2021},
url={http://pubs.sciepub.com/jfnr/9/10/4},
issn={2333-1240},
abstract={<b>Background/Objective:</b> Repeated freezing and thawing results in the structural, compositional, and functional modifications in food materials. The present study was designed to optimize the effect of Freeze-thaw treatment (FTT) on free radical scavenging and linoleic acid reduction potentials of <i>N</i><i>elumbo</i><i> nucifera</i> rhizome starch (NNRS). <b>Methodology:</b> A 4-factorial response-surface central composite design (CCD) based on three levels of each of the four input factors including freezing temperature (F<SUB>T</SUB>: -40, -20, and 0ˇăC), freezing time (F<SUB>t</SUB>: 24, 48, and 72 h), thawing time (T<SUB>t</SUB>: 2, 4, and 6 h), and number of freeze-thaw cycles (FTC: 2, 4, and 6) was constructed. The NNRS was treated at different combinations of input variables as selected by CCD. The Freeze-thaw-treated <i>N. nucifera</i> rhizome starch (FTT-NNRS) was analyzed for antioxidant potential. <b>Principle Findings</b><b>:</b> A statistically significant main effect (<i>p</i>=0.0017-0.0029) of FTT was observed on free radical scavenging and linoleic acid reducing potential (LARP) of NNRS. The 2, 2-diphenylpicrylhydrazyl (DPPH) radical scavenging potential was found to be a linear positive function of F<SUB>T</SUB> and F<SUB>t</SUB> while hydroxyl radical scavenging potential showed a linear linear negative response towards F<SUB>T</SUB> and linear positive response towards FTC<SUB>.</SUB> The LARP also showed a linear positive response towards F<SUB>T</SUB> and T<SUB>t </SUB>and quadratic positive response towards F<SUB>T</SUB>. <b>Conclusion:</b> FTT significantly affected the free radical scavenging potential and LARP of NNRS that may be attributed to the time-dependent variation in the structure of starch and exposure of some antioxidant residues after repeated freezing and thawing treatments.},
doi={10.12691/jfnr-9-10-4}
publisher={Science and Education Publishing}
}