Starch determination, amylose content and susceptibility to in vitro amylolysis in flours from the roots of 25 cassava varieties.
BACKGROUND
Cassava cultivars are classified following different criteria, such as cyanogenic glucoside content or starch content. Here, flours from the roots of 25 cassava varieties cultivated simultaneously in a single plantation, were characterized in terms of starch content (SC), amylose content (AC), α-amylolysis index (AI) and gel formation ability. Resistant starch content (RS) was measured in 10 of the samples.


RESULTS
Cassava flours exhibited high SC, low AC and low AI values, with differences among varieties. Cluster analysis based on these parameters divided the cultivars in four groups differing mainly in SC and AC. AI and AC were inversely correlated (r = -0.59, P < 0.05) in 18 of the cultivars, suggesting AC as an important factor governing the susceptibility to enzymatic hydrolysis of starch in raw cassava. Differences in susceptibility to amylolysis, assessed by RS, were also recorded in the sample subset analyzed. Most flours yielded pastes or gels upon heating and cooling. Gels differed in their subjective grade of firmness, but none exhibited syneresis, confirming the low retrogradation proclivity of cassava starch.


CONCLUSION
Some differences were found among cassava samples, which may be ascribed to inter-cultivar variation. This information may have application in further agronomic studies or for developing industrial uses for this crop.
['Mejía-Agüero|Luisa Elena|LE|', 'Galeno|Florangel|F|', 'Hernández-Hernández|Oswaldo|O|', 'Matehus|Juan|J|', 'Tovar|Juscelino|J|']
D000688:Amylose D000818:Animals D016000:Cluster Analysis D018556:Crops, Agricultural D004044:Dietary Proteins D005511:Food Handling D005782:Gels D006244:Hardness D006868:Hydrolysis D007700:Kinetics D002365:Manihot D055292:Pancreatic alpha-Amylases D044367:Phase Transition D010802:Phylogeny D010940:Plant Proteins D018517:Plant Roots D013045:Species Specificity D013213:Starch D034421:Sus scrofa D014687:Venezuela
amylose content flours resistant starch cassava starch amylolysis rate