| 摘要 |
<p>A liq. or paste food is introduced into an open pref. cylindrical container of a low temp resistant material (e.g. low density polyethylene) and the food is deep frozen in the containers at e.g. -35 degrees C. The container is then introduced into a pref. transparent plastic (e.g. PVC) envelop which is then evacuated so that the envelope clings to the outside of the containers. The mouth of the envelope is gathered up e.g. by twisting, and sealed by pref a metal collar and finally the assembly is immersed for a few seconds in warm water to equalize tensions in the envelope. The method is used for packaging foods to be stored in deep freezers, and is simple and ensures good sealing.</p> |
