Vim li cas qhov sib piv ntawm cistrans yog ib qho ntawm cov lus qhia tseem ceeb tshaj plaws uas yuav tsum tau saib xyuas ntawm Daim Ntawv Pov Thawj ntawm Kev Tshuaj Xyuas Mis Nyuj Lactone?

Qhov no nkag mus rau hauv cov tshuaj lom neeg tshwj xeeb uas txhais tau qhov zoo thiab tus cwj pwm ntawm Milk Lactone.

Nov yog kev piav qhia ntxaws ntxaws:

1. Kev Tshuaj Lom Zem: Vim Li Cas Isomerism Thiaj Tseem Ceeb Hauv Lactones

Rau cov lactones zoo li δ-Decalactone, lub npe "cis" thiab "trans" tsis yog hais txog kev sib txuas ob npaug (zoo li nws ua hauv cov molecules zoo li fatty acids) tab sis rau cov stereochemistry sib piv ntawm ob lub chiral centers ntawm lub nplhaib. Cov qauv nplhaib tsim ib qho xwm txheej uas qhov kev taw qhia ntawm cov hydrogen atoms thiab cov saw alkyl piv rau lub dav hlau nplhaib sib txawv.

· cis-Isomer: Cov hydrogen atoms ntawm cov carbon atoms cuam tshuam nyob rau tib sab ntawm lub nplhaib dav hlau. Qhov no tsim ib lub duab tshwj xeeb, txwv ntau dua.

· trans-Isomer: Cov hydrogen atoms nyob rau sab nraud ntawm lub nplhaib. Qhov no tsim ib lub molecule sib txawv, feem ntau tsis nruj heev.

Cov qhov sib txawv me me ntawm cov duab no ua rau muaj qhov sib txawv tseem ceeb hauv qhov uas cov molecule cuam tshuam nrog cov ntxhiab tsw, thiab yog li ntawd, nws cov aroma profile.

2. Qhov sib piv ntawm cov khoom ntuj thiab cov khoom siv dagMis nyuj Lactone

Qhov Chaw Ib Txwm Muaj Cis Isomer Feem Pua Feem Pua Trans Isomer Feem Pua Qhov Tseem Ceeb

Ntuj (los ntawm Mis Nyuj) > 99.5% (Zoo 100%) < 0.5% (Tsis muaj lossis tsis muaj) Txoj kev enzymatic biosynthesis hauv nyuj yog stereospecific, tsim tsuas yog (R)-daim ntawv uas ua rau cis-lactone.

Cov Khoom Siv Ua Los Ntawm Tshuaj ~70% – 95% ~5% – 30% Feem ntau cov kev tsim cov tshuaj lom neeg (piv txwv li, los ntawm cov tshuaj petrochemicals lossis ricinoleic acid) tsis yog cov khoom sib xyaw ua ke, ua rau muaj kev sib xyaw ntawm cov isomers (ib qho racemate). Qhov sib piv tseeb nyob ntawm cov txheej txheem tshwj xeeb thiab cov kauj ruam ntxuav.

3. Kev Cuam Tshuam ntawm Kev Xav: Vim Li Cas Cis Isomer Thiaj Tseem Ceeb

Qhov feem pua ​​​​​​ntawm isomer no tsis yog tsuas yog kev xav paub txog tshuaj lom neeg xwb; nws muaj qhov cuam tshuam ncaj qha thiab muaj zog rau qhov zoo ntawm kev hnov:

· cis-δ-Decalactone: Qhov no yog lub isomer nrog lub aroma zoo heev, muaj zog, creamy, zoo li txiv duaj, thiab mis nyuj. Nws yog cov tshuaj uas muaj txiaj ntsig zoo rauMis nyuj Lactone.

· trans-δ-Decalactone: Cov isomer no muaj qhov tsw qab tsis zoo, tsis tshua muaj tus cwj pwm, thiab qee zaum txawm tias muaj ntxhiab "ntsuab" lossis "roj". Nws pab me ntsis rau qhov saj creamy uas xav tau thiab tuaj yeem ua rau qhov tsw qab tsis huv lossis hloov pauv qhov huv ntawm cov ntxhiab.

4. Kev cuam tshuam rau Kev Lag Luam Qab thiab Tshuaj Tsw Qab

Qhov feem pua ​​ntawm cis rau trans isomer yog lub cim tseem ceeb ntawm qhov zoo thiab tus nqi:

1. Cov Lactones Ntuj (los ntawm Mis Nyuj): Vim tias lawv yog 100% cis, lawv muaj qhov tsw qab tiag tiag, muaj zog, thiab xav tau tshaj plaws. Lawv kuj yog cov kim tshaj plaws vim yog cov txheej txheem kim ntawm kev rho tawm los ntawm cov khoom mis nyuj.

2. Cov Tshuaj Lactones Zoo: Cov chaw tsim khoom siv cov txheej txheem tshuaj lom neeg lossis cov txheej txheem enzymatic siab heev los ua kom tau qhov ntau tshaj plaws ntawm cov cis isomer (piv txwv li, ua tiav 95% +). COA rau cov tshuaj lactone zoo tshaj plaws feem ntau yuav qhia meej txog cov ntsiab lus cis siab. Qhov no yog qhov tseem ceeb uas cov neeg yuav khoom xyuas.

3. Cov Tshuaj Lactones Uas Siv Tau: Yog tias muaj cov cis tsawg dua (piv txwv li, 70-85%) qhia tias cov khoom tsis zoo. Nws yuav muaj ntxhiab tsw tsis zoo, tsis zoo li qub thiab siv rau hauv cov ntawv thov uas tus nqi yog qhov tseem ceeb thiab tsis tas yuav tsum muaj ntxhiab tsw zoo tshaj plaws.

Xaus lus

Hauv kev xaus, qhov sib piv tsis yog tus lej ruaj khov tab sis yog qhov qhia tseem ceeb ntawm keeb kwm thiab zoo:

Hauv xwm, qhov feem pua ​​​​​​ntawm cov tshuaj no feem ntau yog skewed rau >99.5% cis-isomer.

Hauv kev tsim cov tshuaj, qhov sib piv sib txawv, tab sis cov ntsiab lus cis-isomer siab dua ncaj qha cuam tshuam nrog cov aroma zoo dua, ntuj dua, thiab muaj zog dua.

Yog li ntawd, thaum ntsuas qhov piv txwv ntawm cov khoomMis nyuj Lactone, qhov sib piv cis/trans yog ib qho ntawm cov lus qhia tseem ceeb tshaj plaws uas yuav tsum tau saib xyuas ntawm Daim Ntawv Pov Thawj Tshawb Fawb (COA).