Xanthan cov pos hniav tam sim no yog qhov zoo tshaj plaws biogel nyob rau hauv cov nqe lus ntawm thickening, ncua kev kawm ntawv, emulsification, thiab stability thoob ntiaj teb. Tus nqi ntawm pyruvate pawg ntawm qhov kawg ntawm molecular sab saw ntawm xanthan cov pos hniav muaj qhov cuam tshuam loj rau nws cov khoom. Xanthan cov pos hniav muaj cov yam ntxwv ntawm cov saw hlau ntev ntev, tab sis nws muaj ntau pawg ua haujlwm ntau dua li cov polymers zoo tib yam thiab nthuav tawm cov khoom tshwj xeeb hauv cov xwm txheej tshwj xeeb. Nws conformation nyob rau hauv aqueous tov yog ntau haiv neeg, exhibiting txawv yam ntxwv nyob rau hauv txawv tej yam kev mob.

1. Suspension thiab emulsifying zog

Xanthan cov pos hniav muaj qhov cuam tshuam zoo rau cov khoom tsis sib haum thiab cov roj tee. Xanthan gum sol molecules tuaj yeem tsim super bonded helical copolymers, tsim cov gel tsis yooj yim xws li cov qauv sib txuas uas tuaj yeem pab txhawb lub cev ntawm cov khoom, cov tee dej, thiab npuas, ua kom pom muaj zog emulsifying stability thiab muaj peev xwm raug ncua.

2. Zoo solubility dej

Xanthan cov pos hniav tuaj yeem yaj sai sai hauv dej thiab muaj dej solubility zoo. Tshwj xeeb tshaj yog soluble hauv dej txias, nws tuaj yeem tshem tawm cov txheej txheem nyuaj thiab siv tau yooj yim. Txawm li cas los xij, vim nws qhov muaj zog hydrophilicity, yog tias dej ntxiv ncaj qha yam tsis muaj qhov sib tov txaus, cov txheej txheej sab nrauv yuav nqus dej thiab nthuav mus rau hauv cov gel, uas yuav tiv thaiv cov dej nkag mus rau hauv txheej sab hauv thiab cuam tshuam rau nws cov txiaj ntsig. Yog li ntawd, nws yuav tsum tau siv kom raug. Sib tov xanthan cov pos hniav qhuav hmoov los yog cov hmoov qhuav ntxiv xws li ntsev thiab qab zib, thiab maj mam ntxiv rau hauv dej nplawm kom ua cov tshuaj siv.

3. Thickening khoom

Xanthan cov pos hniav muaj cov yam ntxwv ntawm qis concentration thiab siab viscosity (qhov viscosity ntawm 1% aqueous tov yog sib npaug rau 100 npaug ntawm cov gelatin), ua rau nws muaj txiaj ntsig thickener.

4. Pseudoplasticity

Cov pos hniav xanthan muaj viscosity siab nyob rau hauv zoo li qub los yog tsis tshua muaj shear tej yam kev mob, thiab pom ib tug ntse txo nyob rau hauv viscosity nyob rau hauv siab shear tej yam kev mob, tab sis cov qauv molecular tseem tsis hloov. Thaum lub zog shear raug tshem tawm, qhov qub viscosity yog tam sim ntawd rov qab los. Kev sib raug zoo ntawm shear quab yuam thiab viscosity yog tag nrho cov yas. Lub pseudoplasticity ntawm xanthan cov pos hniav yog qhov tseem ceeb heev, thiab qhov pseudoplasticity no zoo heev rau stabilizing suspensions thiab emulsions.

5. Stability rau cua sov

Lub viscosity ntawm xanthan cov pos hniav tsis hloov pauv nrog qhov kub thiab txias. Feem ntau, polysaccharides tau hloov viscosity vim cua sov, tab sis viscosity ntawm xanthan gum aqueous tov tseem yuav luag tsis hloov ntawm 10-80 ℃. Txawm tias tsis tshua muaj concentration aqueous daws tseem muaj qhov ruaj khov siab viscosity tshaj qhov kub ntau. Cua sov 1% xanthan gum tov (muaj 1% poov tshuaj chloride) ntawm 25 ℃ to 120 ℃ tsuas yog txo nws cov viscosity los ntawm 3%.

6. Stability rau acidity thiab alkalinity

Xanthan cov pos hniav yog ruaj khov rau acidity thiab alkalinity, thiab nws viscosity tsis cuam tshuam ntawm pH 5-10. Muaj qhov hloov pauv me ntsis ntawm viscosity thaum pH tsawg dua 4 thiab siab dua 11. Nyob rau hauv qhov pH ntau ntawm 3-11, qhov siab tshaj plaws thiab qhov tsawg kawg nkaus viscosity qhov sib txawv ntawm tsawg dua 10%. Xanthan cov pos hniav tuaj yeem yaj hauv ntau cov kua qaub, xws li 5% sulfuric acid, 5% nitric acid, 5% acetic acid, 10% hydrochloric acid, thiab 25% phosphoric acid. Cov xanthan cov pos hniav cov kua qaub no ruaj khov heev ntawm chav tsev kub thiab yuav tsis hloov qhov zoo rau ob peb lub hlis. Xanthan cov pos hniav tuaj yeem yaj hauv cov tshuaj sodium hydroxide thiab muaj cov khoom ua kom tuab. Qhov kev daws teeb meem yog ruaj khov heev ntawm chav tsev kub. Xanthan cov pos hniav tuaj yeem degraded los ntawm cov oxidants muaj zog xws li perchloric acid thiab persulfate, thiab degradation accelerates nrog nce kub.

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