Abstract
The effects of emulsifiers on starch retrogradation and/or firming were investigated by kinetic treatment of static viscoelastic parameters for non-glutinous rice starch gels (30%). The anti-firming ability of the sucrose mono ester of various fatty acids (C8 through C18) increased with increasing fatty acid chain length, and possessed maximal efficiency at palmitate (C 16) ester. However, the ability of food grade emulsifiers consisting of a mixture of stearate and palmitate (70: 30) and having various hydrophilic residues was not proportionally affected to an amylose complexing ability, but strongly influenced by hydrophlle-lipophile balance (HLB) values. Among sucrose esters having varied HLB values, the best anti-firming ability was obtained when HLB value was 11. These results suggest that the anti-firming efficiency of emulsifiers on starch gels might be attributed to the multiple effects between the amylose or amylopectin forming complexes with the lipophilic portion (fatty acid), and the hydration of the hydrophilic portion with water molecules in the starchwater systems.
