Abstract: The microbial life and color life of fresh meat products are extended by placing fresh meat in a tray, sealing the fresh meat in the tray in an atmosphere that excludes oxygen and contains carbon monoxide, and applying ionizing radiation to the tray containing the fresh meat. The color life of the fresh meat in the tray may be controlled (such as to be equal to or less than the microbial life) by employing a permeable element and an impermeable element to seal the fresh meat in the tray. The impermeable element is removed at a time after ionizing radiation has been applied, so that the atmosphere that excludes oxygen and contains carbon monoxide is exchanged for ambient atmosphere, resulting in predictable limiting of color life of the fresh meat.

Abstract: A method of providing extended shelf life fresh meat products involves irradiating the meat products in a first controlled atmosphere and packaging the irradiated meat products in a second controlled atmosphere. The packaged irradiated meat products are then distributed to a retail store. In an exemplary embodiment, the first controlled atmosphere excludes oxygen and the second controlled atmosphere is high in oxygen. In one particular embodiment of the present invention, an antioxidant is added to the meat products either prior to or following the step of irradiating the meat products in the first controlled atmosphere, to extend the color-life of the meat products.

Abstract: Articles are irradiated by positioning an article to be irradiated in a processing area, controlling an atmosphere in the processing area to exclude oxygen, and applying radiation to the article in the processing area. In one embodiment, the article is positioned in the processing area by conveying the article on a top surface of a product conveyor in the processing area. One exemplary article for irradiation is a tray of fresh ground meat. The tray of fresh ground meat that is positioned in the processing area for irradiation may itself exclude oxygen as well.

Abstract: An irradiation assembly is effective to irradiate large articles, up to about 48 inches thick in an exemplary embodiment. The assembly provides radiation to an article from all sides in a 360 degree exposure range, and includes at least one irradiating subsystem that provides x-ray radiation in a portion of the 360 degree exposure range. A conveying system carries the article through the at least one irradiating subsystem in a number of passes appropriate to provide x-ray radiation to the article in the full 360 degree exposure range. Each irradiating subsystem is configured to direct radiation toward a center point of the article being irradiated. An accelerator generates an electron beam, and a magnet assembly shapes and deflects the electron beam in a sweep path through a scan horn. A compound bending magnet directs the electron beam toward a center point of the article being irradiated along the entire sweep path. An x-ray conversion plate converts the electron beam into an x-ray radiation beam.

Abstract: An irradiation system includes a conveying system for moving material to be irradiated through a processing area. An irradiation source applies radiation to material in the processing area. The conveying system is enclosed by a sealed conduit in at least the processing area, providing the capability to control the atmosphere inside the sealed conduit and to clean the interior of the sealed conduit according to industrial sanitation methods.

Abstract: A method of providing extended shelf life fresh meat products involves irradiating the meat products in a first controlled atmosphere and packaging the irradiated meat products in a second controlled atmosphere. The packaged irradiated meat products are then distributed to a retail store. In an exemplary embodiment, the first controlled atmosphere excludes oxygen and the second controlled atmosphere is high in oxygen. In one particular embodiment of the present invention, an antioxidant is added to the meat products either prior to or following the step of irradiating the meat products in the first controlled atmosphere, to extend the color-life of the meat products.

Abstract: An irradiation system includes a conveying system for moving material to be irradiated through a processing area. An irradiation source applies radiation to material in the processing area. The conveying system is enclosed by a sealed conduit in at least the processing area, providing the capability to control the atmosphere inside the sealed conduit and to clean the interior of the sealed conduit according to industrial sanitation methods.