真空(kong)袋(dai)(dai)的(de)(de)(de)主(zhu)要(yao)作(zuo)(zuo)用(yong)(yong)是(shi)除(chu)氧(yang)(yang)(yang)(yang)，以有(you)利于防(fang)止食(shi)(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)(bian)質(zhi)(zhi)，其(qi)原(yuan)理也比較簡單，因食(shi)(shi)(shi)(shi)(shi)品(pin)霉腐(fu)變(bian)(bian)(bian)質(zhi)(zhi)主(zhu)要(yao)由微(wei)(wei)(wei)(wei)生(sheng)(sheng)物的(de)(de)(de)活動造成，而(er)大多數微(wei)(wei)(wei)(wei)生(sheng)(sheng)物（如霉菌(jun)和(he)(he)(he)(he)酵母菌(jun)）的(de)(de)(de)生(sheng)(sheng)存是(shi)需要(yao)氧(yang)(yang)(yang)(yang)氣的(de)(de)(de)，而(er)真空(kong)包裝就是(shi)運用(yong)(yong)這(zhe)個(ge)(ge)原(yuan)理，把包裝袋(dai)(dai)內(nei)和(he)(he)(he)(he)食(shi)(shi)(shi)(shi)(shi)品(pin)細胞內(nei)的(de)(de)(de)氧(yang)(yang)(yang)(yang)氣抽掉，使(shi)微(wei)(wei)(wei)(wei)物物失去(qu)“生(sheng)(sheng)存的(de)(de)(de)環(huan)境”。實驗證(zheng)明(ming)：當包裝袋(dai)(dai)內(nei)的(de)(de)(de)氧(yang)(yang)(yang)(yang)氣濃度≤1%時，微(wei)(wei)(wei)(wei)生(sheng)(sheng)物的(de)(de)(de)生(sheng)(sheng)長(chang)和(he)(he)(he)(he)繁(fan)殖(zhi)速(su)度就急劇下降，氧(yang)(yang)(yang)(yang)氣濃度≤0.5%時，大多數微(wei)(wei)(wei)(wei)生(sheng)(sheng)物將(jiang)受到抑制(zhi)而(er)停止繁(fan)殖(zhi)。（注：真空(kong)包裝不能抑制(zhi)厭氧(yang)(yang)(yang)(yang)菌(jun)的(de)(de)(de)繁(fan)殖(zhi)和(he)(he)(he)(he)酶反應(ying)引(yin)起的(de)(de)(de)食(shi)(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)(bian)質(zhi)(zhi)和(he)(he)(he)(he)變(bian)(bian)(bian)色(se)，因此(ci)還需與(yu)其(qi)它輔助方法結合，如冷藏(zang)、速(su)凍(dong)、脫水、高溫殺菌(jun)、輻照 滅菌(jun)、微(wei)(wei)(wei)(wei)波殺菌(jun)、鹽腌制(zhi)等。）真空(kong)除(chu)氧(yang)(yang)(yang)(yang)除(chu)了抑制(zhi)微(wei)(wei)(wei)(wei)生(sheng)(sheng)物的(de)(de)(de)生(sheng)(sheng)長(chang)和(he)(he)(he)(he)繁(fan)殖(zhi)外(wai)，另一個(ge)(ge)重要(yao)功(gong)能是(shi)防(fang)止食(shi)(shi)(shi)(shi)(shi)品(pin)氧(yang)(yang)(yang)(yang)化(hua)，因油脂類食(shi)(shi)(shi)(shi)(shi)品(pin)中含有(you)大量不飽和(he)(he)(he)(he)脂肪酸，受氧(yang)(yang)(yang)(yang)的(de)(de)(de)作(zuo)(zuo)用(yong)(yong)而(er)氧(yang)(yang)(yang)(yang)化(hua)，使(shi)食(shi)(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)(bian)味、變(bian)(bian)(bian)質(zhi)(zhi)，此(ci)外(wai)，氧(yang)(yang)(yang)(yang)化(hua)還使(shi)維生(sheng)(sheng)素(su)A和(he)(he)(he)(he)C損失，食(shi)(shi)(shi)(shi)(shi)品(pin)色(se)素(su)中的(de)(de)(de)不穩(wen)定物質(zhi)(zhi)受氧(yang)(yang)(yang)(yang)的(de)(de)(de)作(zuo)(zuo)用(yong)(yong)，使(shi)顏色(se)變(bian)(bian)(bian)暗。所(suo)以，除(chu)氧(yang)(yang)(yang)(yang)能有(you)效地(di)防(fang)止食(shi)(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)(bian)質(zhi)(zhi)，保(bao)持其(qi)色(se)、香(xiang)、味及營(ying)養(yang)價(jia)值。