Identifying one or more source units for one or more food items may include assigning a sequence of numbers to a plurality of source units received at a processing entity and assigning a sequence of numbers to a plurality of end product units processed from the plurality of source units at the processing entity. A production rate associated with the end product units may be determined from a bill of materials associated with the end product units. A probability distribution function may be generated using at least the production rate. The probability distribution function maps a range of the sequence numbers associated with the plurality of source units to a range of sequence numbers associated with the end product units. A conversion algorithm may be generated that uses the probability distribution function to determine a source unit associated with a selected end product unit.