บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Study on characteristics of vacuum cooling for agriculture products.

Lee W.O., Yun H.S., Lee K.H., Jeong H., Lee H.D., Cho KI.H., Kim M.S.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.72

2004

บทคัดย่อ

Study on characteristics of vacuum cooling for agriculture products.  Prefer temperature manipulation is represented in general by Cold Chain System, and in this system, fruit and vegetables are immediately precooled after harvests and distributed under cold package throughout entire system.In these procedures, the effect of precooling absolutely overwhelms initial quality of fruit and vegetables, and particularly, with vacuum precooling, the temperature of green groceries can be reduced in the early stage of Cold Chain System as an efficient cooling method.

In order to design an efficient vacuum cooling system, a test has been carried out to examine cooling characteristics that changed according to vacuum pressure of the vacuum cooling system in a pilot size and manipulation of the system, and the test results have revealed that the evaporation index of moisture affects mainly cooling speed during the period of time immediately until the pressure in the chamber is controlled evenly at fresh point, and also it has revealed that if the pressure in the chamber is consistent, quality of green groceries and its weights are maintained almost uniformly.In addition, if the specific surface area of the object is large, the test reveals that cooling speed increases faster.However, during the period of time when the final pressure and the temperature of green groceries become stable, it displays a tendency of decreasing weight.

The ratio in connection with the temperature lowering and the amount of weight loss during this period of time brings a decrease of cooling time.It is believed that evaporation of moisture due to radiation heat around the surface of object during the time causes a decrease of weight.Thus, the final level of pressure to reach in chamber has been confirmed as an important parameter to decide the final temperature of object.