The study was conducted to understand the relationship between
molecular architecture and degree of amylolysis in starches
(normal, waxy, and high-amylose genotypes) from wheat and corn
(used extensively in food and industrial applications) with two
under-utilized starches such as triticale and barley. The molecular
characteristics and branching parameters of AP of the above
starches varied significantly (p < 0.05), as a function of botanical
origin and genotypes. In all starches, isolated AP and AM were
hydrolyzed to a higher extent during the initial stages of hydrolysis
than native granules. In isolated AP and AM from normal and highamylose
starches, AP was hydrolyzed to a greater extent than AM.
The difference in DH during the initial stages of amylolysis by a
mixture of a-amylase and glucoamylase reflected variations in the
average AP chain length. High DH was correlated with a high proportion
of short AP branch chains. The relationship between molecular
characteristics of AP and amylolysis of native granules
suggested that triticale and barley were comparable to corn and
wheat with regards to food and industrial applications. For
example, triticale and barley starches, which are composed mainly
of short AP branch chains, can be utilized to produce both sugar
derivatives and bioethanol in which quantitative conversion of
starch to sugar is preferred. On the other hand, corn and wheat
starches with a lesser proportion of short AP chains and a slower
rate of amylolysis are ideal for the development of low-glycemic
foods rather than for bioethanol production.