A dispersion model for predicting the extent of starch liquefaction by Bacillus licheniformis α-amylase during reactive extrusion

V. Komolprasert, R. Y. Ofoli

Research output: Contribution to journalArticle

  • 13 Citations

Abstract

A Baker-Perkins corotating twin screw extruder was used as a bioreactor to hydrolyze pregelantinized corn starch by thermophilic Bacillus licheniformis α-amylase. The extruder was modeled as a tube, and characterized as a closed system. This characterization is not in the thermodynamic sense; rather, it relates to the profile of a tracer fluid upon entry to and exit from the reaction zone. The reaction kinetics were modeled by a modified first-order equation, which allowed the dispersion equation to be solved analytically with the Danckwerts boundary condition. Data from several extrusion runs were super-imposed to obtain a profile to evaluate the model. The dispersion number, determined from the first and second moments of the RTD curve, was primarily a function of the length of the reaction zone. There was good agreement between predictions and experimental data, especially at low dispersion numbers. In general, the axial dispersion model appears to be suitable for analysis of enzymatic reactions of up to 30% conversion. At a fixed flow rate and constant temperature, the extent of starch conversion depends significantly on moisture content, residence time and enzyme dosage, but not on screw speed.

LanguageEnglish (US)
Pages681-690
Number of pages10
JournalBiotechnology and Bioengineering
Volume37
Issue number7
StatePublished - 1991

Profile

Amylases
Bacilli
Liquefaction
Starch
Extrusion
Bioreactors
Extruders
Thermodynamics
Zea mays
Temperature
Enzymes
Reaction kinetics
Moisture
Flow rate
Boundary conditions
Fluids
Bacillus licheniformis alpha-amylase

ASJC Scopus subject areas

  • Biotechnology
  • Microbiology

Cite this

@article{3bcd490a370d4df7acf7bdca091904df,
title = "A dispersion model for predicting the extent of starch liquefaction by Bacillus licheniformis α-amylase during reactive extrusion",
abstract = "A Baker-Perkins corotating twin screw extruder was used as a bioreactor to hydrolyze pregelantinized corn starch by thermophilic Bacillus licheniformis α-amylase. The extruder was modeled as a tube, and characterized as a closed system. This characterization is not in the thermodynamic sense; rather, it relates to the profile of a tracer fluid upon entry to and exit from the reaction zone. The reaction kinetics were modeled by a modified first-order equation, which allowed the dispersion equation to be solved analytically with the Danckwerts boundary condition. Data from several extrusion runs were super-imposed to obtain a profile to evaluate the model. The dispersion number, determined from the first and second moments of the RTD curve, was primarily a function of the length of the reaction zone. There was good agreement between predictions and experimental data, especially at low dispersion numbers. In general, the axial dispersion model appears to be suitable for analysis of enzymatic reactions of up to 30{\%} conversion. At a fixed flow rate and constant temperature, the extent of starch conversion depends significantly on moisture content, residence time and enzyme dosage, but not on screw speed.",
author = "V. Komolprasert and Ofoli, {R. Y.}",
year = "1991",
language = "English (US)",
volume = "37",
pages = "681--690",
journal = "Biotechnology and Bioengineering",
issn = "0006-3592",
publisher = "Wiley-VCH Verlag",
number = "7",

}

TY - JOUR

T1 - A dispersion model for predicting the extent of starch liquefaction by Bacillus licheniformis α-amylase during reactive extrusion

AU - Komolprasert,V.

AU - Ofoli,R. Y.

PY - 1991

Y1 - 1991

N2 - A Baker-Perkins corotating twin screw extruder was used as a bioreactor to hydrolyze pregelantinized corn starch by thermophilic Bacillus licheniformis α-amylase. The extruder was modeled as a tube, and characterized as a closed system. This characterization is not in the thermodynamic sense; rather, it relates to the profile of a tracer fluid upon entry to and exit from the reaction zone. The reaction kinetics were modeled by a modified first-order equation, which allowed the dispersion equation to be solved analytically with the Danckwerts boundary condition. Data from several extrusion runs were super-imposed to obtain a profile to evaluate the model. The dispersion number, determined from the first and second moments of the RTD curve, was primarily a function of the length of the reaction zone. There was good agreement between predictions and experimental data, especially at low dispersion numbers. In general, the axial dispersion model appears to be suitable for analysis of enzymatic reactions of up to 30% conversion. At a fixed flow rate and constant temperature, the extent of starch conversion depends significantly on moisture content, residence time and enzyme dosage, but not on screw speed.

AB - A Baker-Perkins corotating twin screw extruder was used as a bioreactor to hydrolyze pregelantinized corn starch by thermophilic Bacillus licheniformis α-amylase. The extruder was modeled as a tube, and characterized as a closed system. This characterization is not in the thermodynamic sense; rather, it relates to the profile of a tracer fluid upon entry to and exit from the reaction zone. The reaction kinetics were modeled by a modified first-order equation, which allowed the dispersion equation to be solved analytically with the Danckwerts boundary condition. Data from several extrusion runs were super-imposed to obtain a profile to evaluate the model. The dispersion number, determined from the first and second moments of the RTD curve, was primarily a function of the length of the reaction zone. There was good agreement between predictions and experimental data, especially at low dispersion numbers. In general, the axial dispersion model appears to be suitable for analysis of enzymatic reactions of up to 30% conversion. At a fixed flow rate and constant temperature, the extent of starch conversion depends significantly on moisture content, residence time and enzyme dosage, but not on screw speed.

UR - http://www.scopus.com/inward/record.url?scp=0026133637&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0026133637&partnerID=8YFLogxK

M3 - Article

VL - 37

SP - 681

EP - 690

JO - Biotechnology and Bioengineering

T2 - Biotechnology and Bioengineering

JF - Biotechnology and Bioengineering

SN - 0006-3592

IS - 7

ER -