TY - JOUR
T1 - Extrusion of banana starch
T2 - Characterization of the extrudates
AU - González-Soto, Rosalia A.
AU - Mora-Escobedo, Rosalva
AU - Hernández-Sánchez, Humberto
AU - Sánchez-Rivera, Mirna
AU - Bello-Pérez, Luis A.
PY - 2007/1/30
Y1 - 2007/1/30
N2 - Extrusion of banana starch was carried out for obtaining extrudates with functional and digestibility characteristics. Experimental design with temperature, screw speed and moisture content as independent variables produced 20 experiments that were studied using response surface methodology to discover the effect of these variables on resistant starch content, water absorption index and water solubility index. The amylose content was 37.4% with high resistant starch (RS) content in the ungelatinized sample, which decreased when banana starch was gelatinized (1.9%). Extrudate samples had a higher RS content than the gelatinized native starch, showing that the extrusion process increased RS content of native starch due to starch depolymerization and during cooling of extrudates those linear chains form an arrangement that cannot be hydrolyzed by α-amylase. The response surface regression model fitted to experimental results of resistant starch showed good determination coefficient (84%). During model validation for RS, the model explains the experimental results up to 90%. Response surface showed that water absorption index values were high when the temperature, moisture content and screw speed were also high; water solubility values were not affected by screw speed, and both temperature and moisture content had a quadratic effect. Cylindrical structures were observed in powders where RS was present and as RS level increased the cylinders became coarser.
AB - Extrusion of banana starch was carried out for obtaining extrudates with functional and digestibility characteristics. Experimental design with temperature, screw speed and moisture content as independent variables produced 20 experiments that were studied using response surface methodology to discover the effect of these variables on resistant starch content, water absorption index and water solubility index. The amylose content was 37.4% with high resistant starch (RS) content in the ungelatinized sample, which decreased when banana starch was gelatinized (1.9%). Extrudate samples had a higher RS content than the gelatinized native starch, showing that the extrusion process increased RS content of native starch due to starch depolymerization and during cooling of extrudates those linear chains form an arrangement that cannot be hydrolyzed by α-amylase. The response surface regression model fitted to experimental results of resistant starch showed good determination coefficient (84%). During model validation for RS, the model explains the experimental results up to 90%. Response surface showed that water absorption index values were high when the temperature, moisture content and screw speed were also high; water solubility values were not affected by screw speed, and both temperature and moisture content had a quadratic effect. Cylindrical structures were observed in powders where RS was present and as RS level increased the cylinders became coarser.
KW - Extrusion
KW - Microscopy
KW - Physicochemical properties
KW - Response surface analysis
KW - Starch
UR - http://www.scopus.com/inward/record.url?scp=33846426413&partnerID=8YFLogxK
U2 - 10.1002/jsfa.2738
DO - 10.1002/jsfa.2738
M3 - Artículo
SN - 0022-5142
VL - 87
SP - 348
EP - 356
JO - Journal of the Science of Food and Agriculture
JF - Journal of the Science of Food and Agriculture
IS - 2
ER -