Study On Atmosphere Storage At Low Temperature Of Mixed Vegetables For Marine Usage

Vegetables are perishable in sailing by refrigeration, the main preservation method, which could be effectively preserved for a longer storage period via controlled or modified atmosphere storage technology. Therefore, controlled or modified atmosphere storage of vegetables is of significant importance to ship sailing. However, there would be lots of kinds of vegetables on board while the capacity and quantity of fresh-keeping storehouses would be usually limited,therefore, the space inside the controlled atmosphere store could be made full use of and the cost could be cut off by the application of the controlled atmosphere storage of mixed vegetables. Until now, there have been very few researches on the controlled or modified atmosphere storage of mixed vegetables, most of which were focused on the modified atmosphere packaging of mixed fresh-cut vegetables. Thus, it’s indispensable to study the controlled atmosphere storage of mixed vegetables, which might turn to be very important for its application in sailing.The research on the comparison between the controlled atmosphere storage of one kind of vegetable and that of mixed vegetables was carried out to demonstrate the feasibility of controlled atmosphere storage of mixed vegetables; the optimum gas composition parameters of different teams of mixed vegetables under controlled atmosphere was studied by the application of controlled atmosphere storage of several kinds of vegetables blended; the changes of nutrient composition and length of comprehensive storage period of different teams of different kinds of blended vegetables under controlled atmosphere were carried out. The aim of this research was to provide a theoretical basis for the application of controlled atmosphere storage of mixed vegetables in the ship navigation.The differences of the main nutrients, the content of ascorbic and chlorophyll, weight loss, color and sensory quality of celery between the controlled atmosphere storage of mixed pakchoi, lettuce, cabbage and celery, and that of celery and the sensory qualities of the other kinds of vegetables(pakchoi, lettuce and cabbage) preserved with celery, and the differences of the main nutrients, the contents of ascorbic and chlorophyll, weight loss, color and sensory quality of pakchoi between the controlled atmosphere storage of mixed pakchoi and lettuce, and that of pakchoi and the sensory quality of the other kind of vegetable(lettuce) preserved with pakchoi, were studied respectively. The results showed that to the 45 th day of the storage period, there was no significant difference of the weight loss, the contents of ascorbic and chlorophyll, color, sensory qualities of celery and pakchoi between the controlled atmosphere storage of mixed vegetables and the controlled atmosphere storage of one kind of vegetable. Meanwhile, to the 45 th day of the storage period, the other vegetables preserved with the two vegetables presented good sensory qualities. These indicated that the controlled atmosphere storage of mixed vegetables would not result in a significant change in the nutritional quality and sensory quality of the original vegetable compared to controlled atmosphere storage of this vegetable, and also would guarantee that the sensory qualities of other kinds of vegetables preserved with the original vegetable under controlled atmosphere could meet the requirement for the preservation.The relatively suitable gas composition for the controlled atmosphere storage of mixed vegetables was determined by the research on the controlled atmosphere storage of mixed pakchoi, cabbage, broccoli and zizania aquatica, and by the research on the controlled atmosphere storage of pakchoi, lettuce and celery cabbage, with the evaluation indexes including weight loss, the content of ascorbic acid, the chlorophyll content, respiratory rate, color and sensory evaluation. The results showed that the suitable gas composition range was 2.0% ~ 3.0% O2, 3.5% ~ 4.5% CO2 for the controlled atmosphere storage of different teams of different kinds of vegetables in order to inhibit the decrease of the nutritional qualities and sensory qualities of vegetables preserved together effectively and even extend the fresh-keeping period of vegetables preserved together as far as possible.The change trend of the main nutritional components of mixed vegetables under controlled atmosphere and the fresh-keeping periods of those vegetables were studied. It was found out that the weight loss and change of colors of vegetables(spinach, Lactuca sativa L. and celery cabbage, or cauliflower, asparagus lettuce and cabbage) could be inhibited, and the loss of ascorbic and chlorophyll was inhibited significantly by the application of controlled atmosphere storage compared to the same kinds of vegetables mixed in refrigeration. Moreover, vegetables could only be preserved in a period less than 45 days by refrigeration, while controlled atmosphere storage of mixed vegetables could prolong the fresh-keeping period of those vegetables beyond 60 days, which meets the realistic demands for its application in sailing.