MRI Technology Finds Application in Food Inspection
Intermagnetics General Corp. (Latham, NY), with 26 years as a major supplier of products to the clinical MR industry, has turned its attention to the food inspection business. In early March, the company announced that they had installed a second fully automated food-quality inspection system for a major food manufacturer based on their magnetic resonance (MR) technology.
In order to meet the customer's stringent product handling and throughput requirements, the $1.25 million system independently inspects multiple packages of the liquid food product stacked in final shipping cartons at a rate of up to 84 packages per minute.
But the system can also measure raw materials, ingredients, and finished products moving in pipes or on conveyors and produce detailed cross section images or output measurements to control systems.
"It has been demonstrated that magnetic resonance (MR) can be used to measure fruit ripeness, sugar content, moisture and oxygen content; fat/water ratio, foreign body contamination, and many other parameters of relevance to the food industry," said Ian Pykett, vice president, Technology Development Operations for Intermagnetics.
Both inspection systems have been individually optimized to perform complete inspections of two different food products, providing on-line diagnostics and calibration verification capability 24-hours-a-day, seven-days-a-week. Setup is "plant manager friendly" and MR measurements can be output directly to the user's automated inspection and control systems.
Key advantages of MR in such applications include the fact that it is non-invasive, non-destructive, and non-contact, and that it can perform bulk (vs. surface) inspections.
Major financial benefits of the recently installed food inspection systems include low operating costs, since the permanent magnets neither require cryogenic refrigeration nor consume electric power, while operating fully automatically with minimal technical supervision. However, examining product stacked in final shipping cartons requires a large inspection system, incorporating sophisticated individual package interrogation technology and resulting in a relatively high capital cost for the initial systems. MR inspection systems for other applications could cost considerably less, depending on the size and functionality required.
Illustration of MR installation with horizontal conveyor.
Magnetic Resonance
Magnetic resonance technology has revolutionized medical imaging since the 1980s. It produces detailed cross-section images of the human body without the radiation risks of x-ray imaging. MR can clearly distinguish the different chemical and physical properties of living tissue and other materials.
How It Works
A strong and uniform magnetic field harmlessly aligns the nuclei of atoms within the subject. Radio-frequency pulses then "tilt" these nuclei out of alignment. When the pulse ends, the nuclei "relax" back into alignment, producing a signal detected by the MR instrument's receiver coil. Advanced computer programs convert that signal into images for medical diagnosis or into measurements for quality control and automation.
Craig Gardner, Intermagnetics' manager for industrial MR systems, said, "Manufacturers are recognizing the important advantages of MR as an industrial inspection and analysis tool. These include the fact that bulk inspections of products, such as foods, can be performed in a non-contact, non-invasive and non-destructive manner without changing the nature of the product or packaging. Furthermore, our fully-automated, self-calibrating control software can provide a low-maintenance, very easy-to-use product readily integrated into the manufacturing environment."
Intermagnetics and its partner, Surrey Medical Imaging Systems, Ltd. of Guildford, England, jointly developed the food-quality inspection system and are working with several organizations in food and other industries to address additional commercial applications of MR technology in process control and quality inspection.
Intermagnetics is a leading developer and manufacturer of low-temperature (LTS) and high-temperature (HTS) superconducting magnets, wire and cable as well as associated low-temperature refrigeration equipment, and radio-frequency (RF) coils, the combination of which is essential to successful application of superconductivity, especially in equipment for Magnetic Resonance Imaging (MRI).
Surrey Medical Imaging Systems, Ltd. develops and builds state-of-the-art digital and analog electronic subsystems as well as software for medical, industrial, and research applications. SMIS application scientists have implemented many innovative techniques based on their experience working with MR users all over the world.
For more information contact: Intermagnetics General Corporation, 450 Old Niskayuna Rd., Latham, NY 12110. Tel: 518-782-1122; Fax: 518-783-2615.
By Pam Ahlberg