Effect of modification of octenyl succinate starch with mineral elements on the stability and rheological properties of oil-in-water emulsions

The objective of this study was to determine the effect of modifying of octenyl succinate starch with mineral elements on the stability and rheological properties of oil-in-water emulsions. Native potato starch was esterified using two levels (3% or 9%) of octenyl succinic anhydride (OSA) and afterwards enriched with metal ions: magnesium, calcium and potassium. Effectiveness of the modification with metal ions was determined using atomic absorption spectroscopy. The oil-in-water (o/W) emulsions formed by the modified starches were analyzed for: emulsifying capacity, droplet size distribution and rheological properties. The presence of potassium ions in OSA starches resulted in a higher stability of the emulsions. Esterification as well as modification with metals contributed to a decrease in volumetric mean diameter of oil droplets. Emulsions formed by starch esterified with OSA in the concentration of 9% and subsequently modified with magnesium, calcium and potassium ions exhibited lower values of shear stress compared to the system prepared from the non-enriched starch. (C) 2016 Elsevier Ltd. All rights reserved.