Abstract: Provided is a production method for a freshness-keeping bag capable of reducing the inflow of oxygen from the outside of the bag to a very low level, and thereby keeping the freshness of a content thereof for a long period of time.

Abstract: Provided is a food degassing bag which has a stable gas venting operation in response to carbon dioxide gas produced in different amounts and by which a gas venting effect can be obtained even when the internal pressure of a storage bag is low. The storage bag is composed of a packaging film layer 1 and a degassing layer 2. A polyethylene layer 2A and an oxygen barrier layer 2B compose the degassing layer 2. In the degassing layer 2, gas venting through-pores 4 are opened. An adhesive layer 3 adheres the packaging film layer 1 and the polyethylene layer 2A of the degassing layer 2 together. The adhesive layer 3 is formed sequentially with non-adhesive portions showing a stripe pattern. The non-adhesive portions form degassing vents leading to the outside of the storage bag.