A method was proposed to reduce the amount of shock experienced by cherry cargos being shipped from Japan’s Yamagata Prefecture to Taipei, Taiwan. In this study, cherries were first packaged in500g plastic containers, which were then loaded into corrugated fiberboard containers two packages per container. A total of10such corrugated fiberboard containers were then loaded into a larger corrugated fiberboard packaging container. This packaging style was found to reduce shock acceleration at the very bottom by half as compared to the ordinary shipping method, in which three two-package boxes were fastened together with the help of plastic bands. Consequently, shock-induced damage to the cherries during export was significantly decreased. In addition, we investigated the shock absorbing effectiveness of the selected cushioning material. We determined that five-mm-thick urethane sheeting could decrease shock acceleration at the very bottom by 1/2.4~1/3.7 and that adding additional sheets could decreased the shock even further. However, we also found that the sheeting other than one at the bottom did not provide sufficient cushioning effects.
The purpose of this study was to establish a deep - flow hydroponic culture system to reduce the degree of bitterness in cucumbers (Cucumis sativus L. 'Kema') which consumers do not favor. The effect of the amount of nitrogen application and the ratio of nitrate and ammonia nitrogen on the degree of bitterness and yield of 'Kema' cucumbers grown in hydroponics was analyzed. Commercially available 90% nitrate nitrogen and 10% ammonia nitrogen fertilizers were used for this study. In conventional cultivation, cucumbers were cultivated with 1/2 units of standard (Ohtsuka-A) nutrient solution. The 'Kema' cucumbers cultivated with 2/3 units of standard nutrient solution were more bitter in taste than the ones cultivated with 1/3 units of standard nutrient solution. 'Kema' cucumbers cultivated with less nitrate nitrogen were less bitter in taste than the ones cultivated conventionally. Moreover 'Kema' cucumbers cultivated with less nitrate and more ammonia nitrogen showed more yield than the ones cultivated conventionally. These findings suggest that the bitterness of 'Kema' cucumbers is related to the amount of nitrate nitrogen; additionally, hydroponic cultivation utilizing less nitrate and more ammonia nitrogen can help maintain the yield.
The influence of cultivation method on the functional components of persimmon leaf tea was investigated using cv. 'Saijo'. Suitable cultivation methods are as follows : ① heavy pruning during winter for the formation of succulent shoots, ② application of double the regular quantity of fertilizer to enhance tree growth, and ③ harvesting of all succulent shoots at each harvest. The leaves harvested in August showed about 50~70% lower ascorbic acid concentration than those harvested in June, resulting in a different leaf quality.
コマツナは収穫後常温下では急速に黄化し,その品質は劣化する。本研究では,1-methylcyclopropene(1-MCP)処理がコマツナの収穫後の品質に及ぼす影響を調べた。コマツナを0.1μℓ/ℓ,0.5μℓ/ℓ,1μℓ/ℓの1-MCPで24時間,20℃暗所下で処理した。また,1-MCP処理を行わなかったものをコントロールとした。1-MCP処理の後,コマツナを有孔ポリエチレン袋に入れ,20℃暗所下で貯蔵した。その結果,コントロールでは貯蔵3日に葉の先端に黄化がみとめられ,スコアは4未満となった。一方,0.1μℓ/ℓ,0.5μℓ/ℓ,1μℓ/ℓの1-MCP処理を行ったコマツナはそれぞれ貯蔵4日,5日,6日から黄化がみとめられた。これらのことから,1-MCP処理により葉の黄化が遅延することが明らかとなった。1μℓ/ℓで処理されたコマツナのクロロフィル含量は貯蔵3日において他の処理区より有意に高く,その後の減少も遅延しており,クロロフィル含量の減少の遅延は黄化を反映していた。また,1-MCP処理はコントロールと比べ重量減少を抑制し,炭酸ガス生成量を抑制した。さらに,1μℓ/ℓの1-MCP処理は貯蔵中のアスコルビン酸およびカロテン含量の減少を著しく抑制した。これらの結果から,1-MCP処理は収穫後のコマツナの品質保持に有効であることが明らかとなった。
衝撃を含む物理的ストレスは,園芸農産物の生理・生物的特性,食味,外観品質などに大きな影響を及ぼす。本研究においては,小さな落下衝撃が緑熟トマトの呼吸速度,エチレン生成送度に及ぼす影響について検討した。初めに,実験途中でのクライマクテリックによる呼吸速度,エチレン生成速度の変化の影響を排除するため,収穫直後のエチレン生成速度から,熟度を詳細・正確に評価することを試みた。その結果,収穫直後のエチレン生成速度が8.2 nmol/kg/h以下であれば,48時間の実験中にクライマクテリックライズに至らず,緑熟状態が維持されることが明らかになった。このスクリーニング手法により,実験期間中に緑熟状態であることを確認したトマトを,5cmの高さからコンクリート床へ1,3,10回落下処理した。このごく小さな落下処理にもかかわらず,トマトの呼吸速度,エチレン生成速度は顕著に上昇した。興味深いことに,エチレン生成速度は1回のみの落下によっても上昇し,その程度は,呼吸速度のそれと比べて大きかった。さらに,落下処理前にエチレン作用阻害剤である1-MCPを処理した場合であっても,10回落下処理では,呼吸速度とエチレン生成速度の上昇は抑えられなかった。これらの結果と,落下処理した果実において目視による損傷が確認されなかったことから,エチレン生成は落下処理によるトマトの生理的変化を最も顕著に示す指標であると考えられた。したがって,エチレン生成速度は,トマト果実における物理的ストレスの発生を敏感に検出する重要な指標として位置づけられる。加えて,エチレン生成速度は,トマトに関して化学的,物理的な処理が代謝や品質に及ぼす影響を解明する研究において,正確で均一な熟度の果実を選択するための有効な指標であると考えられた。
Changes in total vitamin C content in 5 vegetables (paprika, spinach, parsley, broccoli, and pea) were investigated after the application of different food-processing techniques such as freeze-drying (FD), air-drying (AD), retort sterilization (RT). Drying characteristics such as rehydration and color of the vegetables were also evaluated. Among the 3 processing techniques, FD resulted in the highest vitamin C retention ratio in the vegetables. The rehydration ratios of the dried vegetables were determined after the vegetables were immersed in hot water at 80℃ for30min. The rehydration ratios obtained after FD were higher than the corresponding ratios obtained after AD. Moreover, the appearances of the FD-treated vegetables after rehydration were almost the same as those of the fresh vegetables. The degree of color difference between the fresh vegetables and the FD-treated vegetables was lesser than that between the fresh vegetables and the AD-treated vegetables. These findings confirmed that FD was the best method for processing of food items.