Chemical and Functional Properties of Food Saccharides

22
CONTENTS
© 2004 by CRC Press LLC
Analysis of Molecular
Characteristics of Starch
Polysaccharides
Anton Huber and Werner Praznik
22.1 Introduction
22.2 Analytical Strategy
22.3 Granular Level
22.4 Molecular Level
22.4.1 Molecular Dimensions
22.4.2 Molecular Conformation — Branching Analysis
22.4.3 Supermolecular Structures
References
22.1 INTRODUCTION
Starch is the most important form of energy reserve of crop, is formed annually
worldwide in huge amounts, and is of significant commercial importance. The most
important application of starch was and is for food and animal feedstock.
Whereas the main source of starch in Europe is potatoes, in the U.S. most starch
comes from maize. In tropical countries, the major starch source is cassava and most
starch in the Far East is from rice. Quality of starch always was adjusted, historically
by breeding techniques, now additionally by gene technology, in particular, to obtain
highly short-chain branched (scb) waxy-type glucans. 1–4 Today, waxy-mutants are
available for maize, wheat, barley, rice (monocots), and pea and amaranth (dicots)
(1) with modified physicochemical and technological (functional) properties for
single mutants (waxy, amylose, sugary); (2) new functionalities, however, additionally
poor yield and poor germination for double mutants (waxy/amylose, waxy/dull);
(3) no modified starch structure/functionality for gene-dose of single mutants (aeae+
or ae++); and (4) novel functionalities and high yields from intermutants
(wxwx+/++ae).