真空包裝的一種(zhong)(zhong)變種(zhong)(zhong)是充氣包裝。充(chong)氣包裝的主(zhu)要(yao)作(zuo)用(yong)除真(zhen)空包(bao)裝(zhuang)(zhuang)所具備的除氧(yang)保(bao)質功能(neng)外，主(zhu)要(yao)還有(you)(you)抗壓、阻(zu)氣、保(bao)鮮(xian)等(deng)作(zuo)用(yong)，能(neng)更有(you)(you)效 地使(shi)食(shi)(shi)品長期(qi)保(bao)持原有(you)(you)的色、香、味、形(xing)及營養(yang)價值。另外，有(you)(you)許(xu)多食(shi)(shi)品不宜采(cai)(cai)用(yong)真(zhen)空包(bao)裝(zhuang)(zhuang)，而必須采(cai)(cai)用(yong)充氣包(bao)裝(zhuang)(zhuang)。如松(song)脆(cui)易(yi)碎(sui)食(shi)(shi)品、易(yi)結塊(kuai)食(shi)(shi)品、易(yi)變形(xing)走油食(shi)(shi)品、有(you)(you)尖(jian)銳(rui)棱角或硬(ying)度較(jiao)高會刺破包(bao)裝(zhuang)(zhuang)袋的食(shi)(shi)品等(deng)。食(shi)(shi)品經食品真(zhen)空包裝機抽氣包(bao)裝后，充(chong)入一些氣體，使(shi)包(bao)裝袋(dai)內充(chong)氣壓強大于(yu)包(bao)裝袋(dai)外(wai)大氣壓強，能有效地防止食(shi)品(pin)受壓破碎變形(xing)，并不影(ying)響包(bao)裝袋(dai)外(wai)觀及印刷裝潢。