In situ isotopic meat grader

Claim 1

A meat grader for grading a meat sample disposed in a bin of predetermined dimensions wherein said meat sample extends at least about two feet in all directions, said meat grader comprising: at least one probe including a housing containing a scintillation phosphor responsive to gamma rays including 1.46 Mev gamma rays from potassium-40 for producing corresponding light pulses of magnitude systematically related to the energy of the incident gamma rays, and photomultiplier means optically coupled to said phosphor and responsive to said light pulses for producing corresponding electronic pulses of magnitude systematically related to the magnitude of said light pulses, said probe being adapted to penetrate said meat sample in said bin to dispose said phosphor near the center of said meat sample at least about a foot from the margin thereof, differential pulse height discrimination means coupled to the output of said photomultiplier means for selectively responding to such of said electronic pulses as are of a limited range of magnitude including that characteristic of such pulses occasioned by the incidence of said 1.46 Mev gamma rays upon the respective said phosphor by producing corresponding' discriminated signal pulses, counting rate means responsive to said discriminated signal pulses for counting the number of said discriminated signal pulses in a predetermined time interval to provide a gross counting rate signal corresponding to gross counting rate, background counting rate means for providing a background counting rate signal corresponding to the number of discriminated signal pulses in said predetermined period of time occurring with said at least one probe in an environment corresponding to the meat sample in the absence of potassium-40, and differential means responsive to said background counting rate signal and said gross counting rate signal for producing a net counting rate signal corresponding to the difference between said gross counting rate and said background counting rate is a net counting rate corresponding to 1.46 Mev gamma rays from potassium-40.

Claim 11

A method of grading meat comprising: disposing a meat sample in a bin of predetermined dimensions wherein said meat extends at least about two feet in all directions, inserting into said meat sample at least one probe including a housing containing a scintillation phosphor responsive to gamma rays including 1.46 Mev gamma rays from potassium-40 for producing corresponding light pulses of magnitude systematically related to the energy of the incident gamma rays, and a photomultiplier optically coupled to said phosphor and responsive to said light pulses for producing corresponding electronic pulses of magnitude systematically related to the magnitude of said light pulses, said probe being inserted into said meat in said bin to dispose said phosphor near the center of said meat at least about a foot from the margin thereof, selectively detecting such of said electronic pulses as are of a limited range of magnitude including that characteristic of such pulses occasioned by the incidence of said 1.46 Mev gamma rays upon a said phosphor by producing corresponding discriminated signal pulses, counting the number of said discriminated signal pulses in a predetermined time interval while said probe is disposed in said sample to provide a gross counting rate, providing a background counting rate corresponding to the number of said discriminated signal pulses in said predetermined period of time while said at least one probe is in an environment corresponding to the meat sample in the absence of potassium-40, and subtracting said background count from said gross counting rate to produce a net counting rate corresponding to 1.46 Mev gamma rays from potassium-40.

Claim 12

A method of grading meat comprising: disposing a meat sample in a bin of predetermined dimensions wherein said meat extends at least about two feet in all directions, inserting into said meat sample at least one probe including a housing containing a scintillation phosphor responsive to gamma rays including 1.46 Mev gamma rays from potassium-40 for producing corresponding light pulses of magnitude systematically related to the energy of the incident gamma rays, and a photomultiplier optically coupled to said phosphor and responsive to said light pulses for producing corresponding electronic pulses of magnitude systematically related to the magnitude of said light pulses, said probe being inserted into said meat in said bin to dispose said phosphor near the center of said meat at least about a foot from the margin thereof, selectively detecting such of said electronic pulses as are of a limited range of magnitude including that characteristic of such pulses occasioned by the incidence of said 1.46 Mev gamma rays upon a said phosphor by producing corresponding discriminated signal pulses, counting the number of said discriminated signal pulses in a predetermined time interval while said probe is disposed in said sample to provide a gross counting rate, providing a background counting rate corresponding to the number of said discriminated signal pulses in said predetermined period of time while said at least one probe is in an environment corresponding to the meat sample in the absence of potassium-40, and subtracting said background count from said gross counting rate to produce a net counting rate corresponding to 1.46 Mev gamma rays from potassium-40.