OPTIMIZATION OF EXTRUSION CONDITIONS FOR GABA TEA POWDER/CORN GRIT BLEND EXTRUDATES

摘要

γ-aminobutyric acid (GABA) tea powder blended with corn grits to develop a puffed snack foods by the extrusion technology was studied. Response surface methodology (RSM) was used to analyze the effects of screw speed (179, 200, 250, 300, 321 rpm) and GABA tea powder levels (6, 8, 13, 18 and 20%) on the objective attributes of a corn-based GABA tea powder extrudates. Areas of optimum performance were located by superimposing contour graphs for longitudinal expansion, maximum shear force, hardness and water solubility index for compositions and screw speed levels, which established limits of acceptable quality for each factor. Individual contour plots of the different responses were overlaid, and regions meeting the optimum longitudinal expansion of 18.3883 cm/g, hardness of 39.9659 (N), maximum shear force of 5.1670 (N) and water solubility index of 9.1190 (%) were identified at the GABA tea powder level of 12.9577% and the screw speed of 240.6332 rpm, respectively.