真(zhen)空(kong)袋(dai)(dai)的(de)(de)(de)主(zhu)要(yao)作(zuo)(zuo)用(yong)(yong)是除(chu)氧(yang)(yang)，以有(you)(you)利于防(fang)止(zhi)食(shi)(shi)(shi)(shi)品(pin)(pin)變(bian)(bian)質(zhi)(zhi)，其原(yuan)理(li)也比較簡(jian)單，因食(shi)(shi)(shi)(shi)品(pin)(pin)霉腐變(bian)(bian)質(zhi)(zhi)主(zhu)要(yao)由微(wei)生(sheng)(sheng)(sheng)物的(de)(de)(de)活動(dong)造(zao)成，而大(da)(da)多數微(wei)生(sheng)(sheng)(sheng)物（如(ru)霉菌(jun)(jun)和(he)(he)酵母菌(jun)(jun)）的(de)(de)(de)生(sheng)(sheng)(sheng)存(cun)是需要(yao)氧(yang)(yang)氣的(de)(de)(de)，而真(zhen)空(kong)包(bao)(bao)裝就是運(yun)用(yong)(yong)這個原(yuan)理(li)，把包(bao)(bao)裝袋(dai)(dai)內和(he)(he)食(shi)(shi)(shi)(shi)品(pin)(pin)細胞內的(de)(de)(de)氧(yang)(yang)氣抽掉，使微(wei)物物失去“生(sheng)(sheng)(sheng)存(cun)的(de)(de)(de)環境(jing)”。實驗證明(ming)：當包(bao)(bao)裝袋(dai)(dai)內的(de)(de)(de)氧(yang)(yang)氣濃(nong)度≤1%時，微(wei)生(sheng)(sheng)(sheng)物的(de)(de)(de)生(sheng)(sheng)(sheng)長(chang)和(he)(he)繁(fan)殖速(su)度就急劇下降，氧(yang)(yang)氣濃(nong)度≤0.5%時，大(da)(da)多數微(wei)生(sheng)(sheng)(sheng)物將受(shou)到(dao)抑(yi)制(zhi)(zhi)而停止(zhi)繁(fan)殖。（注(zhu)：真(zhen)空(kong)包(bao)(bao)裝不能(neng)抑(yi)制(zhi)(zhi)厭氧(yang)(yang)菌(jun)(jun)的(de)(de)(de)繁(fan)殖和(he)(he)酶(mei)反應(ying)引起(qi)的(de)(de)(de)食(shi)(shi)(shi)(shi)品(pin)(pin)變(bian)(bian)質(zhi)(zhi)和(he)(he)變(bian)(bian)色(se)，因此還需與其它輔助(zhu)方法結(jie)合，如(ru)冷(leng)藏、速(su)凍、脫水(shui)、高溫殺(sha)菌(jun)(jun)、輻照(zhao) 滅菌(jun)(jun)、微(wei)波殺(sha)菌(jun)(jun)、鹽腌(a)制(zhi)(zhi)等。）真(zhen)空(kong)除(chu)氧(yang)(yang)除(chu)了抑(yi)制(zhi)(zhi)微(wei)生(sheng)(sheng)(sheng)物的(de)(de)(de)生(sheng)(sheng)(sheng)長(chang)和(he)(he)繁(fan)殖外，另(ling)一個重要(yao)功能(neng)是防(fang)止(zhi)食(shi)(shi)(shi)(shi)品(pin)(pin)氧(yang)(yang)化(hua)，因油脂類食(shi)(shi)(shi)(shi)品(pin)(pin)中(zhong)(zhong)含有(you)(you)大(da)(da)量不飽和(he)(he)脂肪(fang)酸(suan)，受(shou)氧(yang)(yang)的(de)(de)(de)作(zuo)(zuo)用(yong)(yong)而氧(yang)(yang)化(hua)，使食(shi)(shi)(shi)(shi)品(pin)(pin)變(bian)(bian)味(wei)、變(bian)(bian)質(zhi)(zhi)，此外，氧(yang)(yang)化(hua)還使維生(sheng)(sheng)(sheng)素A和(he)(he)C損失，食(shi)(shi)(shi)(shi)品(pin)(pin)色(se)素中(zhong)(zhong)的(de)(de)(de)不穩定物質(zhi)(zhi)受(shou)氧(yang)(yang)的(de)(de)(de)作(zuo)(zuo)用(yong)(yong)，使顏色(se)變(bian)(bian)暗(an)。所(suo)以，除(chu)氧(yang)(yang)能(neng)有(you)(you)效地防(fang)止(zhi)食(shi)(shi)(shi)(shi)品(pin)(pin)變(bian)(bian)質(zhi)(zhi)，保(bao)持其色(se)、香、味(wei)及(ji)營(ying)養價(jia)值(zhi)。