A kneading device 1 comprising an inner cone 2 and an outer cone 3, wherein the inner cone 2 and the outer cone 3 defines a space 4 in between the inner cone and the outer cone; from a horizontal plane the inner cone 2 inclines and forms an angle ic; from the same horizontal plane the outer cone 3 inclines and forms an angle oc; where the inner cone 2 has an opening in a bottom of the inner cone 2; where both the inner cone 2 and the outer cone 3 continue vertically in an inner extension 5 and an outer extension 6, respectively, wherein a space in between the inner extension 5 and the outer extension 6 is a gap E; where scraping wings 7 extend from a center portion 8 of the kneading device 1 and through the inner cone 2 and the outer cone 3 and towards, but not fixated to, an inner wall 9 of the outer cone 3; and where the outer cone 3 inclines more than the inner cone 2, when viewed from the horizontal plane, so that angle oc>angle ic.
