真空(kong)(kong)(kong)袋(dai)(dai)的(de)(de)(de)(de)(de)主(zhu)要(yao)作(zuo)用是(shi)除氧(yang)(yang)(yang)(yang)(yang)，以(yi)有(you)利于防(fang)止食(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)質，其(qi)原(yuan)理也比較簡(jian)單，因食(shi)(shi)(shi)(shi)品(pin)霉腐變(bian)(bian)質主(zhu)要(yao)由微生(sheng)物(wu)(wu)的(de)(de)(de)(de)(de)活動造(zao)成，而(er)大(da)多數(shu)微生(sheng)物(wu)(wu)（如霉菌(jun)(jun)和(he)(he)酵(jiao)母(mu)菌(jun)(jun)）的(de)(de)(de)(de)(de)生(sheng)存是(shi)需(xu)要(yao)氧(yang)(yang)(yang)(yang)(yang)氣(qi)(qi)(qi)的(de)(de)(de)(de)(de)，而(er)真空(kong)(kong)(kong)包(bao)(bao)裝就是(shi)運(yun)用這個原(yuan)理，把包(bao)(bao)裝袋(dai)(dai)內和(he)(he)食(shi)(shi)(shi)(shi)品(pin)細胞內的(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)(yang)氣(qi)(qi)(qi)抽掉，使微物(wu)(wu)物(wu)(wu)失(shi)去“生(sheng)存的(de)(de)(de)(de)(de)環(huan)境(jing)”。實(shi)驗證明：當包(bao)(bao)裝袋(dai)(dai)內的(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)(yang)氣(qi)(qi)(qi)濃度≤1%時，微生(sheng)物(wu)(wu)的(de)(de)(de)(de)(de)生(sheng)長(chang)和(he)(he)繁(fan)(fan)殖(zhi)(zhi)速度就急劇下降，氧(yang)(yang)(yang)(yang)(yang)氣(qi)(qi)(qi)濃度≤0.5%時，大(da)多數(shu)微生(sheng)物(wu)(wu)將受到抑(yi)制而(er)停(ting)止繁(fan)(fan)殖(zhi)(zhi)。（注(zhu)：真空(kong)(kong)(kong)包(bao)(bao)裝不能抑(yi)制厭(yan)氧(yang)(yang)(yang)(yang)(yang)菌(jun)(jun)的(de)(de)(de)(de)(de)繁(fan)(fan)殖(zhi)(zhi)和(he)(he)酶反應引起(qi)的(de)(de)(de)(de)(de)食(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)質和(he)(he)變(bian)(bian)色(se)，因此(ci)還需(xu)與(yu)其(qi)它輔助方法結合，如冷藏(zang)、速凍、脫水、高溫殺菌(jun)(jun)、輻照 滅菌(jun)(jun)、微波殺菌(jun)(jun)、鹽(yan)腌制等。）真空(kong)(kong)(kong)除氧(yang)(yang)(yang)(yang)(yang)除了抑(yi)制微生(sheng)物(wu)(wu)的(de)(de)(de)(de)(de)生(sheng)長(chang)和(he)(he)繁(fan)(fan)殖(zhi)(zhi)外(wai)(wai)，另一個重要(yao)功能是(shi)防(fang)止食(shi)(shi)(shi)(shi)品(pin)氧(yang)(yang)(yang)(yang)(yang)化(hua)，因油脂(zhi)類(lei)食(shi)(shi)(shi)(shi)品(pin)中含有(you)大(da)量不飽和(he)(he)脂(zhi)肪酸，受氧(yang)(yang)(yang)(yang)(yang)的(de)(de)(de)(de)(de)作(zuo)用而(er)氧(yang)(yang)(yang)(yang)(yang)化(hua)，使食(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)味、變(bian)(bian)質，此(ci)外(wai)(wai)，氧(yang)(yang)(yang)(yang)(yang)化(hua)還使維生(sheng)素A和(he)(he)C損失(shi)，食(shi)(shi)(shi)(shi)品(pin)色(se)素中的(de)(de)(de)(de)(de)不穩(wen)定物(wu)(wu)質受氧(yang)(yang)(yang)(yang)(yang)的(de)(de)(de)(de)(de)作(zuo)用，使顏色(se)變(bian)(bian)暗。所以(yi)，除氧(yang)(yang)(yang)(yang)(yang)能有(you)效地防(fang)止食(shi)(shi)(shi)(shi)品(pin)變(bian)(bian)質，保持(chi)其(qi)色(se)、香、味及營(ying)養價(jia)值。