(A) Each retort shall be equipped with at least one mercury-in-glass thermometer.
(1) Thermometer divisions are to be easily readable to one degree Fahrenheit and the temperature range shall not exceed seventeen degrees Fahrenheit per inch of graduated scale.
(2) Thermometers shall be tested for accuracy against a known accurate standard thermometer upon installation and at least once a year thereafter to ensure their accuracy.
(3) A thermometer that has a divided mercury column or that cannot be adjusted to the standard shall be repaired or replaced before further use of the retort. Thermometers shall be installed where they can be accurately and easily read. Bulbs of indicating thermometers shall be installed either within the retort shell or in external wells attached to the retort.
(4) The mercury thermometer shall be the reference instrument for indicating the processing temperature. The recorder chart shall not be used for this purpose.
(B) Temperature-recording device.
(1) Each retort shall have an accurate temperature-recording device. Graduations on the temperature-recording devices shall not exceed two degrees Fahrenheit within a range of ten degrees Fahrenheit of the processing temperature.
(2) Each chart shall have a working scale of not more than fifty-five degrees Fahrenheit per inch within a range of twenty degrees Fahrenheit of the processing temperature. The temperature chart shall be adjusted to agree as nearly as possible with, but to be in no event higher than, the known accurate mercury-in-glass thermometer during the process time.
(3) A means of preventing unauthorized changes in adjustment shall be provided.
(4) This temperature recording device may be combined with the steam controller and may be a recording-controlling instrument.
(5) The temperature-recorder bulb shall be installed either within the retort shell or in a well attached to the shell.
(C) Steam controller.
Each retort shall be equipped with an automatic steam controller to maintain the retort temperature.
(D) Retort speed timing.
(1) The rotational speed of the retort shall be specified in the scheduled process
(2) The speed shall be adjusted, as necessary, to ensure that the speed is as specified in the scheduled process.
(3) The rotational speed as well as the process time shall be recorded for each retort load processed.
(4) A means of preventing unauthorized speed changes shall be provided.
(E) Air supply and controls.
(1) A means shall be provided for introducing compressed air at the proper pressure and rate, which shall be controlled by an automatic pressure control unit.
(2) A check valve shall be provided in the air supply line to prevent water from entering the system.
(F) Critical factors.
(1) Critical factors specified in the scheduled process shall be measured and recorded on the processing record at intervals of sufficient frequency to ensure that the factors are within the limits specified in the scheduled process.
(2) The minimum headspace of containers, if specified in the scheduled process, shall be measured and recorded at intervals of sufficient frequency to ensure that the headspace is as specified in the scheduled process.
(3) When the product consistency is specified in the scheduled process, the consistency of the product shall be determined by objective measurements on the product taken from the filler before processing and recorded at intervals of sufficient frequency to ensure that the consistency is as specified in the scheduled process.
(4) Minimum closing machine vacuum in vacuum-packed products, maximum fill-in or drained weight, minimum net weight, and percent solids shall be as specified in the scheduled process for all products when deviations from such specifications may affect the scheduled process.