Effect of extrusion conditions and storage temperature on texture, colour and acidity of butter

The effect of extruder shear rate (500, 750, 1125, 1500 and 1750/s), feed temperature (5, 7, 10, 13 and 15 degrees C) and storage temperature (5, 7, 10, 13 and 15 degrees C) on the acid value, colour (L*, a* and b*values) and texture (hardness and adhesiveness) of organic butter was examined. The optimised conditions in terms of extruder shear rate, feed temperature and storage temperature were 1345/s, 13 degrees C and 7 degrees C, respectively. At the optimised conditions; the predicted responses were determined as hardness 42.5g/cm, work softening 67.2%, adhesiveness 42.5gf/cm, acid value 3.4mg KOH/kg and L* value 99.57.