A tray feeding system comprising: • a first conveyor adapted to be used as a buffer conveyor for trays (209, 305), the first conveyor comprising a first conveyor belt including a plurality of spaced apart rollers acting as free running rollers having rotation axis being substantially perpendicular to the conveying direction of the first conveyor, the plurality of spaced apart rollers further being arranged such that the rollers partly extend upward from the carrying surface of the first conveyor belt such that the trays resting on the first conveyor at least partly rest on the rollers, • a second conveyor having a receiving end placed adjacent to an outputting end of the first conveyor, wherein the tray feeding system further comprises a roller interacting means positioned below and adjacent to the carrying surface of the first conveyor belt at an outputting end area of the first conveyor, the roller interacting means being adapted to engage with the rollers upon arriving at the outputting end area when the first conveyor belt is moving forward causing a rotational movement of the rollers positioned within the outputting end area and thus an acceleration of the tray or trays resting on the first conveyor within the outputting end area of the first conveyor towards the receiving end of the second conveyor, wherein the second conveyor is adapted to be used as a tray conveyor where items are placed into the trays by a tray filling means (204, 205), characterized in that the tray feeding system is configured so that during operation the second conveyor is loaded with trays including trays on the receiving end of the second conveyor that act as a stopper for the trays at the outputting end area of the first conveyor when the second conveyor is stopped, wherein the tray feeding system further comprises a control unit configured for controlling the advancing of the first and the second conveyors, wherein the controlling comprises: • speeding up the first conveyor belt, when at least one tray at an outputting end of the second conveyor has fulfilled a pre-defined target, up to a pre-defined first speed value, or maintaining the first conveyor belt at a first speed value, • speeding up the second conveyor belt up to a pre-defined second speed value, • synchronizing the accelerations of the first and the second conveyors such that the space created at the receiving end of the second conveyor subsequent to accelerating the second conveyor is subsequently filled up with at least one tray from the outputting end area of the first conveyor, and subsequently • stopping the second conveyor and reducing the speed of the first conveyor. • a first conveyor adapted to be used as a buffer conveyor for trays (209, 305), the first conveyor comprising a first conveyor belt including a plurality of spaced apart rollers acting as free running rollers having rotation axis being substantially perpendicular to the conveying direction of the first conveyor, the plurality of spaced apart rollers further being arranged such that the rollers partly extend upward from the carrying surface of the first conveyor belt such that the trays resting on the first conveyor at least partly rest on the rollers, • a second conveyor having a receiving end placed adjacent to an outputting end of the first conveyor, • speeding up the first conveyor belt, when at least one tray at an outputting end of the second conveyor has fulfilled a pre-defined target, up to a pre-defined first speed value, or maintaining the first conveyor belt at a first speed value, • speeding up the second conveyor belt up to a pre-defined second speed value, • synchronizing the accelerations of the first and the second conveyors such that the space created at the receiving end of the second conveyor subsequent to accelerating the second conveyor is subsequently filled up with at least one tray from the outputting end area of the first conveyor, and subsequently • stopping the second conveyor and reducing the speed of the first conveyor.