such a temperature greatly facilitates the handling of the meat chunks so that they can be singularizing and sorted by the photometric sorting unit a control circuit for operating one slot of the ejector 66 will now be described with reference to fig4 each pair of photocells and slot has a similar circuit but only one such circuit will be described the output of the photocell 63 is connected to amplifier 100 which amplifies the output signal and applies the amplified signal to a discriminator 102 which is set to produce an output signal when the amplifier output reaches a predetermined level the discriminator output is alternately coupled to an or gate 106 or an and gate 114 through switch 104 similarly the output of photocell 62 is amplified in amplifier 108 and applied to discriminator 110 the same level is set on discriminator 110 as on discriminator 102 the discriminator 110 thus turns on when the output signal from the photocell 62 reaches a predetermined level the output from the discriminator 110 is alternately applied to or gate 106 or and gate 114 through switch 112 switches 104 and 112 are ganged together through means not shown so that the output of both discriminators 102 and 110 are simultaneously applied to the or gate 106 or to the.