NEW STARCHES FROM IMPROVED YELLOW COLORED CASSAVA: ENZYMATIC AND ACID STURDINESS AND POTENTIAL OF INDUSTRIAL UTILIZATION

Abstract

Native  and  gelatinized  starches  from  eight  improved  cassava  varieties  were extracted and subjected to enzymatic and acid hydrolysis in order to highlight their potential of  industrial  application.  The  enzymatic  hydrolysis  showed  that  native  starches  were  less hydrolyzed (8.40–15.80 10^-2 UI/mg of proteins) than the gelatinized ones with values ranged from  1.14.10² UI  (V₂₃)  to 6.93  10² UI/mg  of  proteins  (V₅₄). Thin  layer  chromatography analysis showed glucose and a high  molecular mass  maltodextrin as  the  common products released from both starches. Maltose and another low molecular mass maltodextrin were in addition observed when gelatinized starches were used. The hydrochloric acid solution had showed predominant conversion of V₄, V₅₄ and V₅₅ with maximum values of reducing sugar products  of  about  70,  62,  and  82  µmol,  respectively. The  starch  variety  V₅₂   recorded  the lowest value (36.23 µmol of reducing sugar). Due to the relatively high degrees of hydrolysis and the wide range of industrial application of modified starches products (glucose, maltose and maltodextrins), V₄, V₅₄ and V₅₅ could constitute new exploring sources of starch for the food  and  pharmaceutical  industry  while  V₅₂   could  be  suggested  as  a  raw  material  for  the paper industry and for biofuel production.