Food safety is a critical component of modern day food production. For baked products such as bread, existing methods for detection of foreign objects are typically limited to x-ray and magnetic (metal detection) technologies. Lincoln Agritech developed a new method for the detection of foreign objects based on near-field microwave scattering that, unlike existing commercial microwave methods which are limited to bulk flow of material in a pipe, is applicable to finished bread products.
Foreign objects inside bread loaves can arise from a variety of sources, and though great care is often taken by the bakery, there is always a chance of mechanical breakage in the production line or contamination from animal pests. Human error (such as the dropping of pens, jewellery, etc) is also a potential source of contamination. Air-voids and grain-clumps within bread loaves are often considered an unwanted ‘foreign objects’ and though they are not a health risk they can significantly affect the consistency and quality of the final product.
Lincoln Agritech developed a near-field microwave scattering method that can quickly scan items for foreign objects by simply looking for anomalies or differences in a small number of microwave signals. This microwave signal method is highly sensitive and can detect spheres of glass, plastic, stones or metal with a 2 mm radius.
This food safety commercial project was supported by the Ministry of Business, Innovation and Employment and various New Zealand food manufacturers.