真(zhen)空(kong)除(chu)氧(yang)除(chu)了抑制微生(sheng)物(wu)的生(sheng)長和(he)繁(fan)殖外(wai)，另一個重要功能(neng)是防(fang)止食(shi)(shi)(shi)(shi)品氧(yang)化，因(yin)油(you)脂類(lei)食(shi)(shi)(shi)(shi)品中(zhong)含有大量(liang)不飽(bao)和(he)脂肪酸，受氧(yang)的作用而氧(yang)化，使食(shi)(shi)(shi)(shi)品變(bian)(bian)味(wei)(wei)、變(bian)(bian)質(zhi)(zhi)(zhi)。此外(wai)，氧(yang)化還(huan)使維生(sheng)素A和(he)維生(sheng)素C損(sun)失，食(shi)(shi)(shi)(shi)品色素中(zhong)的不穩定物(wu)質(zhi)(zhi)(zhi) 受氧(yang)的作用，使顏色變(bian)(bian)暗。所以(yi)，除(chu)氧(yang) 能(neng)有效地(di)防(fang)止食(shi)(shi)(shi)(shi)品變(bian)(bian)質(zhi)(zhi)(zhi)，保(bao)持其色、香(xiang)、味(wei)(wei)及營養價值。