Preservation technique of fresh fruit and vegetables by using plasma technology for export

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H05005
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Agricultural environmental engineering/Agricultural information engineering
• Research Institution: Kyushu University
• Principal Investigator: Uchino Toshitaka 九州大学, 農学研究院, 特任教授 (70134393)
• Co-Investigator(Kenkyū-buntansha): 高木 浩一 岩手大学, 理工学部, 教授 (00216615) ; 田中 史彦 九州大学, 農学研究院, 教授 (30284912)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 農業工学 / 農林水産物 / プラズマ / 高電圧 / 青果物輸出 / エチレン分解 / 殺菌 / 加湿

Outline of Final Research Achievements

To export fresh fruit and vegetables in large quantities, a new preservation technique using plasma was studied. Firstly, a dielectric barrier discharge reactor was produced and its performance was tested. Next, a viable count of airborne bacteria exposed to plasma at 5kV of applied voltage decreased by more than 90% when air flow rate was 1L/min. Moreover, ethylene was decomposed by using the reactor and the efficiency of decomposition was calculated and evaluated. Ethylene concentration in a practical storage was successfully predicted based on the relationship between volume of small size chamber and reaction rate constant of ethylene decomposition. In addition, an effective stacking pattern for ethylene decomposition was proposed by CFD analysis. Finally, relative humidity in a 216L　chamber increased by ca. 40% in 30 min by humidifying using an electrostatic atomizer developed.

Free Research Field

ポストハーベスト技術

Academic Significance and Societal Importance of the Research Achievements

高電圧・プラズマを用い、青果物鮮度保持のためのエチレン分解、殺菌、加湿に応用する技術の確立を目指した。エチレン分解ではプラズマと紫外線照射の併用により分解効率が向上することを見出し、また、殺菌試験では原子状酸素とオゾンの殺菌への関わりを明らかにするなど学術的な意義は大きい。
これらの技術により青果物は長期間の鮮度保持を可能にすることが期待され、農産物・食品の輸出に力点が置かれている現在において、腐敗・変敗が起こりやすい青果物の船舶による大量輸送に貢献可能な研究である。