Acid Tus nqi ntawm cov roj noj
Acid Tus nqi ntawm cov roj noj
Txhawm rau kom ntseeg tau qhov zoo thiab kev nyab xeeb ntawm cov roj zaub uas siv tau, cov ntsuas lub cev thiab tshuaj lom neeg xws li cov kua qaub thiab tus nqi peroxide feem ntau siv los ntsuas lawv qhov zoo. Acid value (AV) yog ib qho kev qhia ntawm cov rog dawb (FFA) cov ntsiab lus hauv cov roj thiab cov rog. Qhov qis dua tus nqi acid, qhov zoo ntawm cov roj, qhov fresher thiab ntau refined nws yog. AV siab qhia tias cov roj tsis zoo los yog tau khaws cia ntev dhau lawm thiab tau dhau los ua oxidatively rancid. Lub ntsiab yog vim li cas rau cov kua qaub ntau dhau yog, thawj zaug, kev tsim cov txheej txheem teeb meem, thiab qhov thib ob, lub sijhawm cia ntev dhau lawm. Thaum lub sij hawm ntev - khaws cia, cov roj thiab cov rog maj mam hydrolyze nyob rau hauv qhov kev txiav txim ntawm cov kab mob, enzymes thiab cua sov los tsim FFA, uas ua rau muaj kev nce hauv AV. Crude roj ntawm tej yam ntuj tso tsiaj thiab nroj tsuag roj muaj ib tug npaum li cas ntawm FFA, xws li xibtes roj, sunflower roj, soybean roj, rapeseed roj, thiab lwm yam. Yog li ntawd, roj cov khoom yuav tsum txo nws cov ntsiab lus rau kev ruaj ntseg qauv thaum siv thiab khaws cia.
Cov txheej txheem ntau lawm rau kev tshem tawm FFA los ntawm cov roj thiab cov rog hauv kev ua lag luam feem ntau hu ua "deacidification". Cov txheej txheem tseem ceeb suav nrog alkali refining deacidification (neutralization cov tshuaj tiv thaiv ntawm alkali tshuaj nrog dawb fatty acids) thiab lub cev deacidification (nqus distillation). Tshwj xeeb tshaj yog:
Alkali refining yog hais txog cov tshuaj tiv thaiv ntawm alkali nrog cov kua qaub los tsim fatty acid ntsev. Cov fatty acids ntsev tsim nyob rau hauv cov txheej txheem daim ntawv saponin nyob rau hauv lub coexistence ntawm roj thiab dej. Saponin tseem yuav adsorb qee cov impurities (xws li cov khoom siv, cov proteins, colloids, pigments, thiab lwm yam) thiab cais lawv los ntawm cov roj los ntawm sedimentation. Qhov no kuj yog chemical refining txoj kev peb paub.
Physical deacidification: this method includes a degumming step, in which FFA are removed by a combination of steam stripping and deodorization. This process is more suitable for high daily production capacity (>10 TSI).
