食品膨化機由供料系統、擠壓系統、加熱系統、傳動系統、旋切系統和控制系統等幾部分組成。將物料由喂料機喂入，機筒經過高溫、高壓、高剪切，使物料膨化以達到所需的組織狀態等品質要求。

食(shi)(shi)品(pin)膨(peng)化(hua)(hua)機是(shi)通(tong)過水(shui)分、熱能、機械(xie)剪切(qie)和壓(ya)(ya)力(li)等綜合作用(yong)(yong)對食(shi)(shi)品(pin)進(jin)(jin)行(xing)膨(peng)化(hua)(hua)的(de)(de)一(yi)種(zhong)技術，是(shi)高(gao)(gao)溫(wen)、高(gao)(gao)壓(ya)(ya)的(de)(de)短時(shi)加工(gong)過程。當(dang)含有(you)一(yi)定水(shui)分的(de)(de)原(yuan)料(liao)通(tong)過供料(liao)器進(jin)(jin)入套筒(tong)后，隨著(zhu)螺桿的(de)(de)轉動而(er)向(xiang)前(qian)輸送，當(dang)物(wu)料(liao)逐漸受(shou)到(dao)機頭的(de)(de)阻力(li)作用(yong)(yong)時(shi)而(er)被(bei)(bei)壓(ya)(ya)縮，通(tong)過壓(ya)(ya)延(yan)效(xiao)應和吸收機筒(tong)外(wai)部(bu)所加熱量，以(yi)及物(wu)料(liao)在螺桿與套筒(tong)間的(de)(de)強烈攪拌、混合、剪切(qie)等作用(yong)(yong)而(er)產生的(de)(de)高(gao)(gao)溫(wen)、高(gao)(gao)壓(ya)(ya)，使物(wu)料(liao)在擠壓(ya)(ya)腔內成(cheng)(cheng)熔(rong)融狀態，淀(dian)(dian)粉(fen)(fen)組織中(zhong)排列緊密的(de)(de)膠束被(bei)(bei)破壞，淀(dian)(dian)粉(fen)(fen)由生淀(dian)(dian)粉(fen)(fen)(β一(yi)淀(dian)(dian)粉(fen)(fen))轉化(hua)(hua)為熟淀(dian)(dian)粉(fen)(fen)(α一(yi)淀(dian)(dian)粉(fen)(fen))，即形成(cheng)(cheng)了淀(dian)(dian)粉(fen)(fen)糊化(hua)(hua)，此時(shi)物(wu)料(liao)中(zhong)的(de)(de)水(shui)分仍處于(yu)液體(ti)狀態。當(dang)熔(rong)融態物(wu)料(liao)進(jin)(jin)入成(cheng)(cheng)型模(mo)頭前(qian)的(de)(de)高(gao)(gao)溫(wen)高(gao)(gao)壓(ya)(ya)區時(shi)，呈完全的(de)(de)流體(ti)狀態，隨模(mo)孔被(bei)(bei)擠出到(dao)達常(chang)溫(wen)常(chang)壓(ya)(ya)狀態，物(wu)料(liao)中(zhong)的(de)(de)溶膠淀(dian)(dian)粉(fen)(fen)體(ti)積也瞬間膨(peng)化(hua)(hua)，致使食(shi)(shi)品(pin)內部(bu)爆裂出許多(duo)微孔，體(ti)積迅速膨(peng)脹，從而(er)形成(cheng)(cheng)質構疏松(song)的(de)(de)膨(peng)化(hua)(hua)食(shi)(shi)品(pin)。