Kawm txog kev hloov kho ntawm cov roj txiv ntoo
Nrog rau txoj kev loj hlob ntawm kev lag luam roj, cov roj ntuj tsis tuaj yeem ua tau raws li qhov xav tau ntawm kev lag luam khoom noj. Qhov no xav kom cov roj ntuj yuav tsum tau ua qee yam txhais tau tias los txhim kho lawv cov khoom ua haujlwm. Lub ntsiab kev hloov kho ntawm xibtes roj yog extraction, hydrogenation thiab transesterification.
1. Pam roj fractionation
Cov roj fractionation feem ntau siv hauv kev lag luam yog: qhuav fractionation, nto active solvent fractionation, thiab hnyav fractionation. Ntawm lawv, qhuav fractionation yog txoj kev sib cais yooj yim tshaj plaws. Tab sis lub sij hawm crystallization ntawm txoj kev no yog ntev li 24h, thiab ntau lawm efficiency yog qis dua nyob rau hauv qhov tseeb ntau lawm. Tang Hongzhou thiab lwm tus tau txhim kho cov xibtes roj qhuav fractionation txheej txheem, hloov cov xibtes roj crystallization txheej txheem los ntawm kev ua kom txias tsis hais lub sij hawm mus rau ib tug staged crystallization txoj kev ceev ceev txias, qhov kub thiab txias txias nyob rau hauv ob peb lub sij hawm. Cov txheej txheem txhim kho tuaj yeem ua kom luv lub sij hawm crystallization, txo kev siv zog, txhim kho kev tsim khoom, thiab pab tswj cov khoom ruaj khov. Guo Shaohai et al. taw qhia tias qhov crystallization kub rov qab tshwm sim tshwm sim nyob rau hauv cov xibtes roj qhuav fractionation txheej txheem. Qhov kub rov qab yog tshwm sim los ntawm qhov siab lossis qis melting point ntawm RBD xibtes roj, los yog qhov tsis zoo crystallization nkhaus. Thiab raws li qhov sib txawv ntawm qhov kub thiab txias, cov kev daws teeb meem raug muab tso rau tom ntej.
2. Hydrogenation ntawm xibtes roj
Hydrogenation feem ntau yog siv los hloov cov kua zaub roj rau hauv cov roj hmab semi-solid. Nws tuaj yeem hloov pauv cov khoom siv roj zaub nrog ntau qhov chaw thiab tus nqi qis rau hauv cov khoom tsim nyog rau kev tsim tshuaj, thiab tau txais ntau yam khoom siv roj ntsha xws li margarine, shortening thiab cocoa butter hloov tau zoo. Piv txwv li, CAI Yunsheng et al. saturated palm kernel soft fat (melting point feem ntau yog 24 ~ 30 degree) los ntawm hydrogenation kom tau hydrogenated xibtes roj nrog melting point ntawm txog 35 degree, yog li ua ice cream nrog zoo zoo, uas zoo heev hloov cov kev ua tau zoo ntawm xibtes roj.
3. Xibtes roj transesterification
Transesterification yog cov tshuaj tiv thaiv uas ib qho ester yog tov nrog lwm cov roj fatty acid, cawv, nws tus kheej los yog lwm yam ester thiab nrog rau acyl exchange lossis molecular rearrangement los tsim ib tug tshiab ester. Cov roj txiv roj thiab cov roj txiv maj phaub roj feem ntau tau hloov pauv los ntawm transesterification kom lawv haum rau ntau yam khoom qab zib, margarine, ua noj thiab kib roj. Nyob rau hauv lub xub ntiag ntawm methyloleic acid tom qab fractionation, tshuaj transesterification tuaj yeem ua rau cov ntsiab lus oleic acid thiab txhim kho kev ua haujlwm ntawm xibtes roj. Transesterification thev naus laus zis tau siv dav hauv kev tsim cov roj xibtes ntawm cov khoom siv qis trans margarine thiab shortening, cocoa butter hloov thiab txheej kev lag luam. Ib qho zoo low trans margarine tau tsim los ntawm enzymatic transesterification ntawm soybean roj thiab xibtes roj. Kuj tseem muaj qhov qis qis trans margarine ua los ntawm xibtes mos thiab xibtes tawv los ntawm transesterification catalyzed los ntawm 1,3 tshwj xeeb lipases.
