Effect of isoamylase application on chemical characteristic of cassava root meal starch

Abstract

Cassava root meal (CRM) is still rarely used as an ingredient for poultry feed. The high viscosity component can be reduced by enzymatic hydrolysis. However, there is limited information about enzyme treatment on cassava root meal. The objective was to identify and evaluate the effect of isoamylase hydrolysis on the chemical characteristic of hydrolyzed cassava root meal starch which has amylose/amylopectin ratio approached the corn. The cassava root meal was weighed each 200 g containing five levels of isoamylase (CRM-A) 0.01%, (CRM-B) 0.02%, (CRM-C) 0.03%, (CRM-D) 0.04%, (CRM-E) 0.05% (w/w) were moistened with 135 ml distilled water and incubated to at 50 °C for 12 hours. Total starch, amylose, amylopectin, total sugar, and reducing sugar content of hydrolyzed product were measured. The result showed that there were increasing of total starch and amylose content of hydrolyzed cassava root meal and decreasing in amylopectin content and amylose/amylopectin ratio. Reducing sugar increased along with increasing enzyme addition 1.81 – 3.07% DM which corresponds to degree of hydrolysis to 54.52 – 72.99%. It can be concluded that the different levels of isoamylase addition will produce cassava root meal starch with different chemical characteristics. The addition 0.05% isoamylase is able to make amylose/amylopectin ratio of hydrolyzed cassava root meal approached the corn.