真(zhen)空(kong)包(bao)裝不(bu)能(neng)抑制(zhi)厭氧(yang)(yang)(yang)(yang)(yang)菌的繁殖和(he)酶反應引起的食(shi)(shi)品變(bian)(bian)(bian)質和(he)變(bian)(bian)(bian)色(se)(se)(se)，因此還(huan)需與其它輔助方法結合，如冷(leng)藏、速凍、脫水(shui)、高溫(wen)殺菌、輻照 滅菌、微波殺菌、鹽腌制(zhi)等(deng)。真(zhen)空(kong)除氧(yang)(yang)(yang)(yang)(yang)除了抑制(zhi)微生物(wu)的生長和(he)繁殖外(wai)，另一個重要功(gong)能(neng)是防止食(shi)(shi)品氧(yang)(yang)(yang)(yang)(yang)化，因油脂(zhi)(zhi)類食(shi)(shi)品中含有(you)(you)大量不(bu)飽和(he)脂(zhi)(zhi)肪酸，受氧(yang)(yang)(yang)(yang)(yang)的作用而(er)氧(yang)(yang)(yang)(yang)(yang)化，使(shi)(shi)食(shi)(shi)品變(bian)(bian)(bian)味、變(bian)(bian)(bian)質，此外(wai)，氧(yang)(yang)(yang)(yang)(yang)化還(huan)使(shi)(shi)維生素A和(he)C損失(shi)，食(shi)(shi)品色(se)(se)(se)素中的不(bu)穩定物(wu)質受氧(yang)(yang)(yang)(yang)(yang)的作用，使(shi)(shi)顏色(se)(se)(se)變(bian)(bian)(bian)暗。所以，除氧(yang)(yang)(yang)(yang)(yang)能(neng)有(you)(you)效地防止食(shi)(shi)品變(bian)(bian)(bian)質，保持其色(se)(se)(se)、香、味及營養價值。