真空充氣包(bao)裝的主要作用除(chu)(chu)真空包(bao)裝所具備的除(chu)(chu)氧保質功能(neng)外，主要還有(you)抗壓、阻氣(qi)、保鮮等作用，能更有(you)效(xiao)地使食(shi)(shi)(shi)品(pin)長期(qi)保(bao)持(chi)原有(you)的(de)色、香、味、形(xing)及營養(yang)價值。另(ling)外，有(you)許(xu)多食(shi)(shi)(shi)品(pin)不適(shi)宜(yi)采(cai)用真(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)(zhuang)而必須采(cai)用真(zhen)空(kong)(kong)(kong)(kong)充(chong)(chong)(chong)氣包(bao)裝(zhuang)(zhuang)(zhuang)。如松脆易碎(sui)食(shi)(shi)(shi)品(pin)，易結(jie)塊食(shi)(shi)(shi)品(pin)，易變形(xing)走油食(shi)(shi)(shi)品(pin)，有(you)尖銳棱角或硬度(du)較高會刺破(po)包(bao)裝(zhuang)(zhuang)(zhuang)袋(dai)(dai)的(de)食(shi)(shi)(shi)品(pin)等。食(shi)(shi)(shi)品(pin)經真(zhen)空(kong)(kong)(kong)(kong)充(chong)(chong)(chong)氣包(bao)裝(zhuang)(zhuang)(zhuang)后(hou)(hou)，包(bao)裝(zhuang)(zhuang)(zhuang)袋(dai)(dai)內充(chong)(chong)(chong)氣壓強(qiang)大于包(bao)裝(zhuang)(zhuang)(zhuang)袋(dai)(dai)外大氣壓強(qiang)，能有(you)效(xiao)地防(fang)止食(shi)(shi)(shi)品(pin)受壓破(po)碎(sui)變形(xing)并不影響(xiang)包(bao)裝(zhuang)(zhuang)(zhuang)袋(dai)(dai)外觀及 印刷裝(zhuang)(zhuang)(zhuang)潢(huang)。真(zhen)空(kong)(kong)(kong)(kong)充(chong)(chong)(chong)氣包(bao)裝(zhuang)(zhuang)(zhuang)在真(zhen)空(kong)(kong)(kong)(kong)后(hou)(hou)再充(chong)(chong)(chong)入(ru)氮氣、二氧化碳(tan)、氧氣單一氣體或二 三種(zhong)氣(qi)(qi)體(ti)(ti)的混合氣(qi)(qi)體(ti)(ti)。其(qi)氮氣(qi)(qi)是(shi)惰性(xing)氣(qi)(qi)體(ti)(ti)，起充(chong)填作(zuo)用(yong)(yong)，使袋內保持正壓 ，以防(fang)止袋外空氣(qi)(qi)進(jin)入袋內，對食品起到一個保護作(zuo)用(yong)(yong)。其(qi)二氧(yang)化(hua)碳能夠溶(rong)于各類(lei)脂肪或水，引成酸性(xing)較弱的碳酸，有(you)(you)抑制霉菌、腐敗(bai)細菌等微生(sheng)物的活(huo)性(xing)。其(qi)氧(yang)氣(qi)(qi)具有(you)(you)抑制厭氧(yang)菌的生(sheng)長繁殖，保持水果(guo)、蔬菜(cai)的新(xin)(xin)鮮及色(se)彩，高濃度氧(yang)氣(qi)(qi)可使新(xin)(xin)鮮肉類(lei)保持其(qi)鮮紅(hong)色(se)。