9 CFR § 96.14 - Uncertified casings; disinfection with saturated brine solution.
Foreign animal casings offered for importation into the United States upon disinfection, may either be disinfected with hydrochloric acid as at present or if preferred may be submerged in a saturated brine solution at a temperature not less than 127 °F. for at least 15 minutes. The time held as well as the temperature of such brine solution must be recorded on a one-hour dial of a recording thermometer and filed in the local APHIS office for official inspection at any time. In order that this required temperature may be more readily maintained, such casings must first be submerged in a brine solution at approximately 127 °F. for about five minutes immediately before the 15-minute recorded submersion period begins. This may be done either in the testing vat or a preliminary vat. By following this procedure the temperature will not vary unduly and thus cause unsatisfactory results. After removing the casings from the testing vat, it will be found advantageous to submerge them in another vat containing cold brine solution or cold water in order to remove the extra heat from the casings as promptly as possible, but of course this is optional with the importer. In order to obtain the most satisfactory results, the hanks, rings, and similar units must be separated as much as possible without untying, but “dolls” will not be permitted to be disinfected by this heating method. In order to keep the temperature of the brine in the testing vat of a uniform degree, it is necessary to agitate the solution occasionally by moving the casings. The tip of the recording thermometer should be located at a point which would be approximately at the bottom of the volume of casings being disinfected.