真空(kong)(kong)(kong)(kong)，這一術(shu)語譯自拉丁文vacuo，其意(yi)義是(shi)虛無。其實(shi)(shi)真空(kong)(kong)(kong)(kong)應理解為氣體較稀薄的空(kong)(kong)(kong)(kong)間(jian)。在(zai)指定的空(kong)(kong)(kong)(kong)間(jian)內(nei)，低于一個大氣壓(ya)力(li)的氣體狀態統稱(cheng)(cheng)為真空(kong)(kong)(kong)(kong)。真空(kong)(kong)(kong)(kong)狀態下氣體稀薄程度(du)(du)稱(cheng)(cheng)為真空(kong)(kong)(kong)(kong)度(du)(du)（degreeofvacuum），通常(chang)用(yong)壓(ya)力(li)值(zhi)表示。因此真空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)(shi)際上不是(shi)完全真空(kong)(kong)(kong)(kong)的，采用(yong)真空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)技術(shu)包(bao)裝(zhuang)的食品容器內(nei)的真空(kong)(kong)(kong)(kong)度(du)(du)通常(chang)在(zai)600-1333Pa。所以，又將真空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)稱(cheng)(cheng)為減壓(ya)包(bao)裝(zhuang)或(huo)排(pai)氣包(bao)裝(zhuang)。