FUNCTIONAL PROPERTIES AND IN VITRO DIGESTIBILITY OF NATIVE AND ACID-THINNED STARCHES FROM THREE NEGLECTED PURPLE CORN VARIETIES FROM CÔTE D’IVOIRE

Abstract

The objective of this study was to promote three purple corn varieties grown in Côte d'Ivoire, namely Katiola Purple. This was achieved by subjecting the starches to thinning, a chemical modification that has been widely employed to enhance their properties. The functional properties and enzymatic digestibility of these modified starches were then compared with those of the native starches. The thinned starches exhibited enhanced clarity and dispersibility, as well as increased hydration capacity. At 90 °C temperature, the thinned starches solubility increased significantly, reaching 66.04 g/g, 59.22 g/g and 62.16 g/g. The TDP, TPR and TLP starches exhibited a solubility of 13.46, 19.35 and 17.61, respectively, while the native NDP, NPR and NLP starches demonstrated values of 13.46, 19.35 and 17.61, respectively. The thinned starches also showed better in vitro digestibility and gelation capacity. The lower gelation concentration (0.5%) renders these thinned starches suitable for the infant food industry. Thinning also resulted in starches with low swelling power and reduced syneresis due to the low amylose content of the thinned starches. The significant reduction in syneresis is a highly noteworthy feature for preserving frozen foods. The acid thinning process has been shown to enhance the functional properties of native starches from purple maize varieties. The findings of this study provide valuable insights into the selection of the most appropriate applications for these starches in the food and non-food industries.

Keywords

• purple corn
• zea mays
• starch
• acid-thinning
• enzymatic digestibility
• functional properties