Enzymatic modification of maize flour improves its functional properties, digestion resistibility, and antioxidant potential

Khan A., Siddiqui S., Rahman U. U., BELDÜZ A. O., Shah A. A., Badshah M., ...More

JOURNAL OF FOOD MEASUREMENT AND CHARACTERIZATION, vol.17, pp.6109-6124, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 17
  • Publication Date: 2023
  • Doi Number: 10.1007/s11694-023-02072-7
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Agricultural & Environmental Science Database, CAB Abstracts, Compendex, Food Science & Technology Abstracts, Veterinary Science Database
  • Page Numbers: pp.6109-6124
  • Keywords: Antioxidant activity, Digestion resistibility, Maize flour, Pullulanase, Resistant starch
  • Karadeniz Technical University Affiliated: Yes


Starches resistant to digestion have been widely used in the food and pharmaceutical applications to develop new products. These starches are naturally not present in maize flour or only in minimal amount. The aim of the present study was therefore to enzymatically modify maize flour in order to increase the yield of resistant starch in corn flour. Previously in our research article, we reported a 16-fold increase in yield of resistant type III starch by amylase hydrolysis. As an extension of that work and to investigate the action of debranching enzymes and their role in production of resistant starch, pullulanase was included in the current study. This increase the yield of resistant starch by a factor of 20-folds under optimized conditions using pullulanase. Scanning electron microscopy and X-ray diffraction analysis showed the transformation of the granular amorphous structure of the starch into a dense network of crystalline form. Thermogravimetric analysis revealed an increased amylose content, while 1H-NMR and 13C-NMR indicated a debranching pattern of pullulanase-treated starch. The radical scavenging test and reducing power illustrate a significant increase in the antioxidant activity of maize flour after pullulanase treatment. In addition, enzymatically modified resistant starch showed slow digestibility and improved ability to complex with iodine, proving it to be a safe capping material for the site-specific delivery of active, sensitive drugs to the colon.