真空包(bao)裝(zhuang)的一種變種是(shi)充(chong)氣包(bao)裝(zhuang)。充(chong)氣(qi)包裝的主(zhu)要作用(yong)(yong)除(chu)真空包(bao)裝(zhuang)所(suo)具備的除(chu)氧保(bao)(bao)質(zhi)功(gong)能外，主(zhu)要還(huan)有(you)(you)抗壓、阻氣、保(bao)(bao)鮮等作用(yong)(yong)，能更有(you)(you)效 地使食(shi)(shi)(shi)品長期保(bao)(bao)持(chi)原(yuan)有(you)(you)的色、香、味(wei)、形(xing)及營養(yang)價值。另外，有(you)(you)許多(duo)食(shi)(shi)(shi)品不宜采用(yong)(yong)真空包(bao)裝(zhuang)，而必須采用(yong)(yong)充氣包(bao)裝(zhuang)。如(ru)松脆易(yi)(yi)碎食(shi)(shi)(shi)品、易(yi)(yi)結塊(kuai)食(shi)(shi)(shi)品、易(yi)(yi)變形(xing)走油食(shi)(shi)(shi)品、有(you)(you)尖銳棱角或硬(ying)度較(jiao)高會刺(ci)破包(bao)裝(zhuang)袋的食(shi)(shi)(shi)品等。食(shi)(shi)(shi)品經食品真空包裝機抽氣(qi)包裝(zhuang)后，充(chong)入一(yi)些(xie)氣(qi)體，使包裝(zhuang)袋(dai)內充(chong)氣(qi)壓強(qiang)(qiang)大于包裝(zhuang)袋(dai)外大氣(qi)壓強(qiang)(qiang)，能有效地(di)防止(zhi)食品受壓破碎變(bian)形，并不影(ying)響包裝(zhuang)袋(dai)外觀及印刷裝(zhuang)潢。