Development of Inspection Technology for Foreign Materials in Food Using Sub-Terahertz Waves

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K15628
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 41040:Agricultural environmental engineering and agricultural information engineering-related
• Research Institution: Mie University (2023); Kyoto University (2020-2022)
• Principal Investigator: Suzuki Tetsuhito 三重大学, 生物資源学研究科, 准教授 (00723115)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 異物検査 / サブテラヘルツ波 / ミリ波 / 透過強度分布 / 粉末食品 / 回折模様

Outline of Final Research Achievements

A line inspection system combining a belt conveying system for powdered food, a light source and an imaging system with a line sensor was constructed using sub-THz waves (millimeter-wave) and the features of the device, and the detection performance of low-density foreign material in parsley was evaluated. Foods were fed evenly to the transmission imaging system using a 100 GHz (3-mm wavelength) light source through a belt conveyor and leveling mechanism, which enabled imaging with minimal background noise and a circular diffraction pattern was observed on the foreign material. Quantitative evaluation of the image change of the foreign object showed that foreign objects larger than 2 mm could be detected significantly, and a robust foreign object judgement model was constructed using neural network analysis, which resulted in a correct judgement rate of 85%.

Free Research Field

農業情報工学

Academic Significance and Societal Importance of the Research Achievements

特に農産物由来の食品に対し、虫、プラスチック片などの異物が混入したニュースは後を絶たず、企業の損失回避ならびに食の安心・安全の向上のため、新しい異物検出技術が求められている。本研究は、従来は検出が難しかった低密度の異物を対象にしてライン検査により自動で混入異物を判定できるシステム構築を目指したものであり、従来は人の目で多大な労力と時間をかけてきた検査作業を軽減することに貢献できるものと期待される。