Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 7/11/1997 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: An optimized method recently developed to quantify the degree of branching in alpha-glucans using proton nuclear magnetic resonance (NMR) will be described in terms of instrument parameters and sample preparation. The method was used to determine relative amounts of amylose and amylopectin in starch samples from a variety of sources, with good correlation to iodine binding based analyses. In the process of these amylose/amylopectin determinations, it was observed that there is apparently more than one type of amylopectin, based on its degree of branching. New terminology is proposed to describe the different types of amylopectin. In addition, the new branching degree method was used to determine the number average molecular weight of various maltodextrins and starches, with comparisons to other commonly used methods. The effect of common processing techniques, such as extrusion, on starch branching will be discussed in terms of the branching ratios of extruded products from a variety of conditions. Finally, attempts were made to correlate branching fraction of starch samples to other starch properties, such as cooking behavior and viscosities, to generate the maximum information possible about a starch sample from a single, fast type of analysis. |