Detection of a novel three component complex consisting of starch, protein, and free fatty acids.
A water soluble three way complex composed of starch, whey protein, and free fatty acid (FFA) was detected in a dilute three component system after heating. In high-performance size exclusion chromatography (HPSEC) profiles of the starch-protein-FFA system, the three way complex eluted between amylopectin and amylose. The molecular mass of the complex, based on multiangle laser light scattering/HPSEC and pullulan standards, was estimated to be approximately (6-7) x 10(6) Da. Carbohydrate measurement by the phenol-sulfuric acid method clearly showed that the starch amylose fraction shifted to a higher molecular weight elution volume following complexation. Whey protein existed as large disulfide-linked aggregates and is speculated to be the organizer of the three way complex. Differential scanning calorimetry of the freeze-dried complex showed the presence of an amylose-FFA melting endotherm, thus proving that FFA was the third component in the three way complex and that the amylose-FFA complex was one of the structural components of the complex. The complexation mechanism and its relationship with changes in starch functionality were discussed.
Zhang
Genyi
G
Department of Food Science and the Whistler Center for Carbohydrate Research, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN 47907-2009, USA.
Maladen
Michelle D
MD
Hamaker
Bruce R
BR
D000687:Amylopectin / Q000032:analysis; D000688:Amylose / Q000032:analysis; D002152:Calorimetry, Differential Scanning; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005230:Fatty Acids, Nonesterified / Q000032:analysis / Q000302:isolation & purification*; D006358:Hot Temperature; D008894:Milk Proteins / Q000032:analysis / Q000302:isolation & purification*; D008970:Molecular Weight; D013213:Starch / Q000032:analysis / Q000302:isolation & purification*; D000067816:Whey Proteins
D005230:Fatty Acids, Nonesterified; D008894:Milk Proteins; D000067816:Whey Proteins; D013213:Starch; D000688:Amylose; D000687:Amylopectin