| Optimization conditions for Japanese green tea snack production were investigated using response surface methodology. A central composite design with four independent variables: screw speed (116, 150, 200, 250 and 284 rpm); feed rate (28.8, 32.0, 38.3, 44.7 and 47.9 g/min); moisture content (13.0, 14.0, 16.0, 18.0 and 19.0 %) and vegetables or herbs content (0.0, 1.0, 3.0, 5.0 and 6.4 %) was use to study the response variables such as expansion ratio, bulk density, hardness, crispness, antioxidant activity, total phenolic and resistant starch content. A second-degree equation for independent and response variables was computed and used to create the contour and surface plot graphs. The screw speed at 196 rpm, feed rate of 44.7 g/min, moisture... |
