African Journal of
Food Science

  • Abbreviation: Afr. J. Food Sci.
  • Language: English
  • ISSN: 1996-0794
  • DOI: 10.5897/AJFS
  • Start Year: 2007
  • Published Articles: 756

Full Length Research Paper

Impact of electric voltages on the emulsification capabilities of okra seed protein-rich extract

Uhiara N. S.
  • Uhiara N. S.
  • Department of Food Science and Technology, Department of Electrical Engineering, Federal Polytechnic, Bauchi, Nigeria.
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Onwuka G. I.
  • Onwuka G. I.
  • Department of Food Science and Technology, Department of Electrical Engineering, Federal Polytechnic, Bauchi, Nigeria.
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Nwabueze T. U.
  • Nwabueze T. U.
  • Department of Food Science and Technology, University of Agriculture Umudike, Nigeria.
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Anosike M.
  • Anosike M.
  • Department of Food Science and Technology, Department of Electrical Engineering, Federal Polytechnic, Bauchi, Nigeria.
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  •  Received: 25 March 2014
  •  Accepted: 28 September 2015
  •  Published: 30 April 2018

Abstract

A portion of okra seed protein-rich extract (PRE) prepared with NaCl solution (5 g/L) was hydrolyzed at 110°C for 5 h (1 atm. pressure). The PRE (sample A), hydrolyzed PRE-B, whole okra seed flour-C and gelatin-D were tested for emulsification capacity (EMC) and emulsion stability (ES). The emulsions were prepared and tested in (i) normal environmental condition (o/w and w/o), (ii) current carrying beaker-CB, (iii) Ohmic heating beaker-OB. The tests were carried out at zero to 240 V. The results showed that at 200 V, the EMC were 85.71, 80.50, 88.23, 85.31, 94.71, 94.70, 90.68, and 83.3% for ACB, AOB, BCB, BOB, CCB, COB, DCB, and DOB, respectively. The respective ES are 23, 31, 25, 43, 98, 61, 98, and 65%. At 200 V, okra product CCB had the highest EMS and ES (94 and 98%, respectively). At 95% oil (w/o) emulsion, EMC for PRE and gelatin were 6.0 and 1.9%, respectively. At 5% oil (o/w) emulsion, the corresponding EMS and ES is 84 and 94%. Hydrolyzed okra seed PRE-CCB is possibly a hydrophilic emulsifier, combining high (94%) EMC with high (98%) ES. 

Key words: Okra seed, protein-rich extract, hydrolysis, emulsification, electric field.