Also the grains couldn't be ground as finely, since the equipment didn't exist, and
therefore, much
less of the grain came in
contact with the digestive track than it does these days.
With a TEV system, the spring inside the TEV allows a certain superheat value to be maintained, and the sensing bulb in
contact with the evaporator's outlet raises the valve's needle allowing more liquid refrigerant inside the evaporator when the outlet becomes warm and
less when it becomes cold, all of this resulting in a vapour with a certain superheat and pressure at the evaporator's exit and
therefore in the suction line.