RAPID QUANTITATIVE MEASUREMENT OF EXTRUSION-INDUCED STARCH FRAGMENTATION BY AUTOMATED GEL-PERMEATION CHROMATOGRAPHY

Gel permeation chromatography with application of the universal calibration concept was found to be a rapid and effective method for quantification of extrusion-induced starch fragmentation. This method (Timpa, J.D., J. Agr. Food Chem. 39 (1991), 270-275) employs dimethyl acetamide (DMAC) with lithium chloride to solubilize samples and automated gel permeation chromatography for fractionation. Instrumentation was equipped with a viscometer and refractometer. data was interpreted by application of the universal calibration concept. These results confirm that the largest starch molecules in corn meal (10(7) to 10(8) Daltons) were slightly prone to fragmentation. Fragments produced were primarily in the weight range of 10(4)-10(7) Daltons. In addition, some smaller fragments (ranging between 5,000 and 7,500) were also generated by extrusion.