Abstract
In this experiment American Summer Pairman apple was selected as test fruit in order to study the effect of sub-atmospheric pressure storage in the apple. keeping a certain pressure condition, a new sub-atmospheric pressure system was designed and constructed in which fruits were stored at $25^{\circ}C$ under two different atmospheric pressure conditions such as Normal Atmospheric Pressure (NAP) and Sub-Atmospheric Pressure (SAP). Moreover, they were divided into plots of 5% and 0% of $CO_2$, on the basis of gas composition. Under these conditions, the amount of respiration and ethylene evolution, and the changes of intercellular gas composition and organic components were investigated throughout the storage. The results obtained are as follows: (1) The intercellular gas was exhausted so rapidly by the SAP treatment that the gas equilibrium in the tissues reached within 5 minutes. (2) The amount of respiration was found to be higher in plots of NAP than SAP, and under the conditions, controlling $CO_2$ content, plots of $CO_2$ 5% were lower in the amount of respiration than $CO_2$ 0%. The climateric rise was revealed more slowly in plots of the SAP than NAP. These results indicate that the SAP treatment was an efficient method for controlling the respiration of fruits. Furthermore, these results were also realized with the results of the respiratory quotient (R.Q) and intercellular gas composition. (3) Evolution of ethylene, the ripening hormone in plant, was shown the similar tendency to the climacteric pattern of respiration; at the stage of climacteric maximum, the maximun amount of ethylene was found earlier in plots of NAP than SAP, and post climacteric stage was prolonged in the plots of the SAP compared to those of the NAP. The ethylene concentration in tissue appeared lower in plots of the SAP than NAP, which might suggest that the SAP treatment was caused to restriction of ethylene evolution. (4) Effects of the SAP treatment mentioned hitherto were proved also with the test of the external appearance such as changes of color and freshness, firmness, rotting and weight loss. (5) In the investigation of organic components, vitamin C and organic acids varied less in plots of SAP than NAP. Specially, it was remarkable that the loss of malic acid was least decreased by the SAP treatment. These effects of the SAP treatment were distinctive in the changes of the ratios of malic and citric acid to total acid, and the ratios of free sugar to free acid.
감압(減壓)이 사과저장(貯藏)에 미치는 영향(影響)을 보기 위하여 일정감압(一定減壓)을 유지(維持)시킬 수 있는 감압저장장치(減壓貯藏裝置)를 새로히 고안제작(考案製作)하여서 시료(試料)는 저장성(貯藏性)이 약(弱)하다는 축(祝)을 선정(選定)하여 $25^{\circ}C$에서 상압구(常壓區)와 감압구(減壓區)로 구분(區分)하고 다시 각(各) 구별(區別)로 환경기체조성(環境氣體組成)을 $CO_2$ 0%구(區) 및 $CO_2$ 5%구(區)로 조정(調整)하여 저장중(貯藏中) 호흡(呼吸), ethylene 생성량(生成量) 및 조직내기체조성(組織內氣體組成)의 변화(變化)와 아울러 성분변화(成分變化)를 조사(調査)하였던 바, 1. 조직내기체(組織內氣體)는 감압(減壓)이 설정(設定)이 동시(同時)에 급속(急速)히 조직(組織)밖으로 이동(移動)하여 5분(分) 이내(以內)에 평형(平衡)이 되었음을 보았으며, 2. 호흡량(呼吸量)은 상압구(常壓區)가 감압구(減壓區)보다 높았고 환경기체조성변화(環境氣體組成變化)에 있어서도 $CO_2$ 5%구(區)는 $CO_2$ 0%구(區)에 비하여 호흡량(呼吸量)이 적음을 볼 수 있었다. 그리고 climacteric rise의 발현(發現)도 호흡량(呼吸量)이 낮음과 병행하여 감압구(減壓區)가 상압구(常壓區)보다 지연됨을 볼 수 있었으며 이와같은 것으로 미루어 감압(減壓)이 과실호흡(果實呼吸)을 억제(抑制)하는데 효과적(效果的)인 수단(手段)임을 알 수 있었다. 이와같은 현상(現像)은 R.Q의 변화조사(變化調査)와 조직내기체조성(組織內氣體組成)의 변화조사(變化調査)에서도 찾아 볼 수 있었다. 3. 과실(果實)의 성숙(成熟) hormone인 ethylene의 생성(生成)은 호흡(呼吸)의 climacteric pattern과 병행하는 경향(傾向)이었으며 climacteric maximum stage,에서는 감압구(減壓區)가 상압구(常壓區)보다 높은 경향(傾向)이었으나 post climacteric stage이후부터 낮아짐과 아울러 조직내(組織內) ethylene농도조사(濃度調査)에서 감압구(減壓區)가 상압구(常壓區)보다 낮음을 볼 때 감압(減壓)으로 인(因)하여 과실(果實)의 ethylene생성(生成)이 억제(抑制)되는 것이 아닌가 생각된다. 4. 그리고 외관조사(外觀調査)에서 지색(地色)의 변화(變化)가 늦어짐과 신선도(新鮮度), 부패율(腐敗率), 중량감소(重量減少), 경도(硬度)의 변화(變化)에서도 위와같은 감압(減壓)의 효과(效果)를 찾아 볼 수 있었다. 5. 성분변화(成分變化) 조사(調査)에 있어서도 당분(糖分), vitamin C 및 산(酸)의 변화(變化)가 감압(減壓)이 상압(常壓)보다 적었으며 특(特)히 유기산중(有機酸中) malic acid의 감소억제효과(減少抑制效果)가 감압구(減壓區)에서 크게 나타났다. 이와같은 효과(效果)는 감산비(減酸比)에서 뚜렷함을 알 수 있었다.