A knife for an equipment for forming a precut in a pack of food cups, said precut facilitating separation by breaking along a separation line between two food cups, wherein the knife comprises a cutting part configured for making a precut groove and/or a full cut along the separation line, wherein said cutting part extends along a first longitudinal axis, such that, seen in section perpendicular to the longitudinal axis, characterised in that the cutting part extends on either side the transverse axis and in that the cutting part comprises: on one side of the transverse axis: - a first portion extending between a first point forming the end of the cutting portion and a second point, wherein the straight line connecting the first and second points (P1, P2) forms a first angle with the transverse axis comprised between 20° and 40°; - a second portion extending between the second point and a third point, wherein the straight line connecting the second and third points (P2, P3) forms a second angle with the transverse axis comprised between 15° and 25°; and on the other side of the transverse axis: - a third portion extending between the first point and a fourth point, wherein the fourth point coincides with the transverse axis; - a fourth portion extending from the fourth point to a fifth point, wherein the fifth point is symmetric to the third point about the transverse axis, and wherein the straight line connecting the fourth and fifth points (P4, P5) forms a third angle with the transverse axis comprised between 15° and 25°. on one side of the transverse axis: - a first portion extending between a first point forming the end of the cutting portion and a second point, wherein the straight line connecting the first and second points (P1, P2) forms a first angle with the transverse axis comprised between 20° and 40°; - a second portion extending between the second point and a third point, wherein the straight line connecting the second and third points (P2, P3) forms a second angle with the transverse axis comprised between 15° and 25°; and - a first portion extending between a first point forming the end of the cutting portion and a second point, wherein the straight line connecting the first and second points (P1, P2) forms a first angle with the transverse axis comprised between 20° and 40°; - a second portion extending between the second point and a third point, wherein the straight line connecting the second and third points (P2, P3) forms a second angle with the transverse axis comprised between 15° and 25°; and on the other side of the transverse axis: - a third portion extending between the first point and a fourth point, - a third portion extending between the first point and a fourth point, wherein the fourth point coincides with the transverse axis; - a fourth portion extending from the fourth point to a fifth point, wherein the fifth point is symmetric to the third point about the transverse axis, and wherein the straight line connecting the fourth and fifth points (P4, P5) forms a third angle with the transverse axis comprised between 15° and 25°. - a fourth portion extending from the fourth point to a fifth point, wherein the fifth point is symmetric to the third point about the transverse axis, and wherein the straight line connecting the fourth and fifth points (P4, P5) forms a third angle with the transverse axis comprised between 15° and 25°.