Muaj Peev Xwm Cuam Tshuam Ntawm Cov Khoom Noj Khoom Noj

Cov nyhuv ntawm cov qauv thiab cov txheeb ze molecular phaus ntawm viscosity: General thickener yog ib hom colloid uas yooj yim los ua cov qauv network lossis muaj ntau pawg hydrophilic hauv kev daws, thiab muaj viscosity siab. Yog li ntawd, cov viscosities ntawm cov tuab nrog cov qauv sib txawv yuav txawv heev txawm tias nyob ntawm tib lub siab thiab hauv lwm yam mob. Nrog rau qhov nce ntawm nruab nrab molecular phaus ntawm tib lub thickener, qhov tshwm sim ntawm txoj kev ua cov qauv network kuj nce. Yog li no, lub viscosity ntawm cov tuab ua yog ze rau tus txheeb ze molecular phaus, uas yog, ntau dua ntawm cov txheeb ze molecular phaus, ntau dua cov viscosity. Lub viscosity ntawm cov khoom noj qis dua hauv cov txheej txheem ntau lawm thiab khaws cia, uas yog qhov tseem ceeb vim qhov kev xeb ntawm cov tuab thiab qhov hnyav ntawm qhov txheeb ze molecular phaus.

Cov nyhuv ntawm kev cuam tshuam ntawm viscosity: nrog qhov nce ntawm thickener concentration, qhov ntim ntawm molecular elasticity ntawm thickener nce, qhov tshwm sim ntawm kev cuam tshuam kev cuam tshuam, thiab tus nqi ntawm cov dej molecules adsorbed nce, yog li ntawd cov viscosity nce.

Cov nyhuv ntawm pH tus nqi ntawm viscosity: tus nqi pH ntawm qhov nruab nrab yog ze rau viscosity thiab ruaj khov ntawm cov tuab. Lub viscosity ntawm thickener feem ntau hloov nrog pH tus nqi. Piv txwv, thaum sodium alginate hauv pH 5-10, lub viscosity yog qhov ruaj khov; thaum tus nqi pH tsawg dua 4.5, qhov viscosity tsub kom pom tseeb (tab sis nyob rau hauv cov xwm txheej no, cov viscosity tsis ruaj khov vim los ntawm cov kua qaub catalytic degradation, yog li nws yog qhov zoo dua los siv nyob rau hauv nruab nrab cov neeg mob nruab nrab). Thaum tus nqi pH yog 2-3, propylene glycol alginate qhia tau ntau tshaj plaws viscosity, thaum sodium alginate precipitates. Cov viscosity ntawm gelatin yog qhov qis tshaj nyob ntawm isoelectric point, tab sis qhov hloov pH tus nqi ntawm xanthan ntawm cov pos hniav (tshwj xeeb tshaj yog nyob ntawm muaj me me ntawm ntsev) muaj cov nyhuv me me ntawm qhov viscosity. Lub hydrolysis ntawm polysaccharide glycoside daim ntawv cog lus yog nqa tawm nyob rau hauv qhov xwm txheej ntawm acid acid. Yog li ntawd, hauv cov zaub mov nrog muaj zog acid nruab nrab, txoj hlua ncaj nraim sodium alginate thiab cov carboxymethyl cellulose sodium nrog cov ntawv tom qab me me yog yooj yim rau thuam, uas ua rau txo viscosity. Yog li ntawd, nws raug nquahu kom xaiv cov glyceryl alginate thiab xanthan ntawm cov pos hniav nrog ntau dua lossis ntau dua sab caj npab, ntau dua kev ua kom tsis haum thiab muaj hydrolysis tsawg dua hauv cov dej haus thiab yoghurt nrog siab acidity. Txawm li cas los xij, sodium alginate thiab CMC yuav tsum siv cov kua mis taum pauv thiab lwm yam khoom noj nruab nrab.

Cov nyhuv ntawm qhov kub ntawm viscosity: nrog rau qhov nce ntawm qhov kub, qhov nrawm ntawm cov lus tsa suab molecular yog nrawm, thiab viscosity ntawm kev daws dav dav txo. Piv txwv li, rau sodium alginate daws nyob rau hauv ib txwm mob, viscosity txo qis li 12% txhua 5-6 ℃ nce ntawm qhov kub. Nrog rau qhov nce ntawm qhov kub thiab txias, qhov ceev ntawm cov tshuaj tiv thaiv yog nce ceev, tshwj xeeb tshaj yog nyob rau hauv cov xwm txheej ntawm cov kua qaub muaj zog, qhov dej ntws hydrolysis ntawm feem ntau colloids yog nrawm. Thaum lub polymer colloid depolymerization, qhov txo ntawm viscosity yog dej tsis hloov. Txhawm rau kom tsis txhob muaj qhov txo qhov tsis pom kev ntawm viscosity, nws yog qhov tsim nyog kom tsis txhob ua kom sov lub colloid tov ntawm qhov kub ntawm lub sijhawm ntev. Nyob rau hauv muaj ib qho me me ntawm sodium chloride, lub viscosity ntawm xanthan ntawm cov pos hniav hloov me ntsis ntawm - 4 ℃ rau + 93 ℃, uas yog ib rooj plaub tshwj xeeb ntawm cov tuab. Xanthan ntawm cov pos hniav thiab propylene glycol alginate muaj zoo thermal stability.

Qhov cuam tshuam ntawm shear quab yuam rau lub viscosity ntawm cov tshuaj thickener: lub viscosity ntawm cov tshuaj thickener nrog qee qhov kev nkag siab yuav hloov nrog kev ua thiab kis tau txhais tau tias xws li nplawm thiab lub twj tso kua mis siab.

Cov nyhuv synergistic ntawm cov thickeners: yog tias cov thickeners tau sib xyaw thiab sib xyaw, cov tshuaj tiv thaiv tuab yuav ua rau cov nyhuv viscosity superposition, uas tuaj yeem ua tau synergistic. Tom qab qee lub sijhawm, viscosity ntawm kev sib xyaw yog ntau dua li qhov viscosity ntawm txhua feem, lossis lub zog siab dua gel tsim. Piv txwv li, cov pos hniav arabic tuaj yeem txo qhov viscosity ntawm cov pos hniav tragacanth. Qee zaum, tsuas muaj ib qho tuab tuab tsis tuaj yeem tau txais cov txiaj ntsig zoo tshaj plaws, yog li nws yuav tsum tau siv nrog lwm cov emulsifiers ua si cov nyhuv synergistic. Cov txiaj ntsig tau pom tias qhov ua tau ntawm cov tuab ntawm qhov hnyav yog CMC thiab gelatin, carrageenan, cov pos hniav guar thiab CMC, agar thiab Robinia taum cov pos hniav, xanthan ntawm cov pos hniav thiab cov pos hniav taum.

Cov cawv ntawm lwm yam cuam tshuam txog viscosity: ntxiv rau pH tus nqi thiab kub, muaj ntau yam cuam tshuam rau viscosity. Lub viscosity ntawm sodium alginate kev daws teeb meem yuav tau nce los ntawm kev ntxiv cov tshuaj tsis tov lossis ntxiv qhov hnyav ntxiv (xws li dej cawv) uas tuaj yeem tsis haum nrog dej, thiab nws thiaj li ua rau muaj nag lossis daus ntawm sodium alginate. Txawm li cas los xij, siab siab ntawm surfactant yuav txo qhov viscosity ntawm sodium alginate, thiab nws thiaj li ua rau alginate ntsev tawm ntawm qhov kev daws, thiab ntsev tshem tawm yuav tseem txo qhov viscosity ntawm dilute sodium alginate. Vim tias muaj qib sib txawv ntawm polymerization, tus txheeb ze molecular qhov sib txawv kuj txawv heev, yog li cov thickener tsis muaj qhov teeb meem sib txheeb ze cov molecular phaus, uas feem ntau qhia los ntawm nruab nrab txheeb ze molecular phaus lossis qhov txheeb ze molecular phaus ntau.