Abstract

Mufumbo Raphael, Baguma Yona, Kashub Stephen , Nuwamanya Ephraim, Rubaihayo Patrick , Mukasa Settumba , Hamaker Bruce and Kyamanywa Samuel

Amylopectin molecular structure is a very important determinant of starch functional properties. The main purpose of this study was to determine the strength of the relationship between the amylopectin structure of starches from cassava varieties and their functional properties. TME14 had the highest (46.63%) proportion of A chains while Bamunanika had the lowest 42.27%. Bamunanika had the highest (23.33%) proportion of B3+ chains while TME14 had the lowest 19.66%. TME14 had the highest amylopectin molecular weight 2.74x108 g/mol while NASE10 had the lowest 2.42x108 g/mol. TME14 had a higher gelatinisation temperature 65.37°C compared to the other varieties. Bamunanika had the highest final viscosity 2477.66 mPa s while NASE10 had the highest set back viscosity (494.50 mPa s). TME14 had the highest pasting temperature 67.80°C while NASE10 had the lowest 65.23°C. There was a significant negative correlation between final viscosity and A chains (r = -0.64), pasting temperature and A chains (r = - 0.77), A, B1 chains and gelatinisation temperature of retrograded starches (r = - 0.82, r = - 0.87), respectively, gyration radius and onset temperature of gelatinisation for the retrograded starch (r -0.56) and a significant positive correlation between B2 chains and pasting temperature (r = 0.94), amylopectin molecular weight and percentage retrogradation (r = 0.66). These findings revealed possible improvement through breeding for starch with desired qualities.