真(zhen)空(kong)充氣(qi)包裝的主要作用除(chu)(chu)真(zhen)空(kong)包裝所具備的除(chu)(chu)氧保(bao)質功(gong)能外(wai)，主要還有抗(kang)壓、阻氣(qi)、保鮮(xian)等作用(yong)，能更有(you)效(xiao)地使食(shi)(shi)(shi)品(pin)長(chang)期保(bao)持原有(you)的色、香、味、形及營養價值。另外(wai)(wai)(wai)，有(you)許(xu)多食(shi)(shi)(shi)品(pin)不(bu)適宜采用(yong)真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)而必(bi)須采用(yong)真(zhen)(zhen)空(kong)(kong)(kong)充(chong)氣(qi)(qi)包(bao)(bao)裝(zhuang)。如松脆易碎(sui)食(shi)(shi)(shi)品(pin)，易結塊食(shi)(shi)(shi)品(pin)，易變(bian)形走油食(shi)(shi)(shi)品(pin)，有(you)尖(jian)銳棱(leng)角或硬度較(jiao)高(gao)會刺(ci)破(po)(po)包(bao)(bao)裝(zhuang)袋的食(shi)(shi)(shi)品(pin)等。食(shi)(shi)(shi)品(pin)經真(zhen)(zhen)空(kong)(kong)(kong)充(chong)氣(qi)(qi)包(bao)(bao)裝(zhuang)后，包(bao)(bao)裝(zhuang)袋內充(chong)氣(qi)(qi)壓(ya)強大于包(bao)(bao)裝(zhuang)袋外(wai)(wai)(wai)大氣(qi)(qi)壓(ya)強，能有(you)效(xiao)地防止食(shi)(shi)(shi)品(pin)受壓(ya)破(po)(po)碎(sui)變(bian)形并不(bu)影響包(bao)(bao)裝(zhuang)袋外(wai)(wai)(wai)觀及 印刷裝(zhuang)潢。真(zhen)(zhen)空(kong)(kong)(kong)充(chong)氣(qi)(qi)包(bao)(bao)裝(zhuang)在(zai)真(zhen)(zhen)空(kong)(kong)(kong)后再(zai)充(chong)入氮氣(qi)(qi)、二(er)氧化(hua)碳、氧氣(qi)(qi)單一氣體或二 三種氣(qi)體的(de)混合氣(qi)體。其氮氣(qi)是(shi)惰性(xing)氣(qi)體，起充填作用，使袋內(nei)保持正壓(ya) ，以防止袋外空氣(qi)進入袋內(nei)，對食品起到一(yi)個保護作用。其二氧化碳能夠溶于各類脂肪或水，引成酸性(xing)較弱的(de)碳酸，有抑制霉(mei)菌、腐敗細菌等微生(sheng)物的(de)活性(xing)。其氧氣(qi)具有抑制厭氧菌的(de)生(sheng)長繁殖，保持水果、蔬菜的(de)新鮮(xian)及色彩(cai)，高濃(nong)度氧氣(qi)可使新鮮(xian)肉類保持其鮮(xian)紅色。