A seed sorting machine contains a feeding area, a plurality of filtration units, a classification assembly, multiple guiding assemblies, a delivery unit, and at least one pressing rod. Each filtration unit includes multiple holding trays, a plurality of first partitions, and each holding tray has a filtering hole. The classification assembly includes a classifying tray, multiple guide sheets, and a plurality of outlets. Each guiding assembly includes a holder and multiple ribs, wherein between any two adjacent of the multiple ribs is defined a slot which corresponds to each of the plurality of outlets. The delivery unit includes a base on which multiple V-shaped grooves and multiple second partitions are arranged. Each pressing rod includes a plurality of rollers and multiple trenches, wherein each of the multiple trenches is defined between any two adjacent of the multiple trenches and corresponds to each of the multiple V-shaped grooves.

A system and method for flaking. The system includes a stationary roller, and moveable roller, and an adjustable fixator applying tension between the stationary and moveable rollers. The fixator includes a pressure transducer and a linear indicator. The transducer and indicator allow the fixator to read pressures and make fine adjustments to the fixator to obtain a desired gap between the two rollers.

A system and method for flaking. The system includes a stationary roller, and moveable roller, and an adjustable fixator applying tension between the stationary and moveable rollers. The fixator includes a pressure transducer and a linear indicator. The transducer and indicator allow the fixator to read pressures and make fine adjustments to the fixator to obtain a desired gap between the two rollers.

A dehulling system for soft-shelled nuts includes at least two dehulling stations arranged in series, where each station is made up of at least one dehulling machine in a first dehulling stage and a screening machine in a second screening stage, both being a first and a second consecutive stages. The screening machine is a densimetric separator located lower than the dehulling machine and has an upper product inlet towards the interior thereof, which comprises a drum arranged according to an inclined plane, a first outlet for the dehulled grain in the upper part of the drum and a second outlet for the rest of materials other than the dehulled grain in the lower part of the drum.