xov xwm

1. Dynamic Evolution ntawm Nitrite

Siv spectrophotometry txuas ntxiv mus saib xyuas cov txheej txheem fermentation, qhov kev sim tau nthuav tawm tus yam ntxwv "ob npaug-nce toj nkhaus" hauv cov ntsiab lus nitrite. Thaum pib theem (0-24 teev), nitrate-txo cov kab mob sai sai hloov nitrates hauv zaub rau nitrite, nce qib mus rau 48 mg / kg. Nyob rau theem ob (hnub 3-5), lactic acid cov kab mob proliferation maj mam decomposed nitrite, nqa qib rov qab mus rau thaj tsam nyab xeeb. Qhov tseem ceeb, txhua txhua 5 ° C nce nyob rau hauv qhov kub thiab txias nce siab tshaj plaws los ntawm 12-18 teev.

Kev sib piv nrog kev lag luam kimchi tau pom tias kev tsim khoom lag luam, los ntawm kev tswj hwm cov xwm txheej (1.5% -2.5% salinity, 15-20 ° C), txwv nitrite peaks qis dua 32 mg / kg. Hauv qhov sib piv, kimchi hauv tsev, feem ntau tsis muaj qhov ntsuas kub, tsis tu ncua ntau dua 40 mg / kg, qhia tias muaj kev pheej hmoo siab dua hauv kev coj ua hauv tsev.

2. Cov ntsiab lus tseem ceeb tswj

Salt concentration plays lub luag haujlwm txiav txim siab hauv microbial tshuav nyiaj li cas. Ntawm salinity qis dua 1%, cov kab mob pathogenic thiab nitrate-txo cov kab mob vam meej, ua rau ua ntej thiab siab dua nitrite peaks. Qhov kev sim tau txheeb xyuas 2.5% salinity raws li qhov zoo tshaj plaws tshuav nyiaj li cas, zoo suppressing kab mob phem thaum txhawb cov kab mob lactic acid metabolism.

Kev tswj qhov kub thiab txias yog qhov tseem ceeb sib npaug. Fermentation ntawm 20 ° C pom qhov ruaj khov microbial kev ua haujlwm. Kub siab tshaj 25 ° C ua kom ceev fermentation tab sis ua rau muaj kev pheej hmoo ntawm microbial imbalance, thaum qis dua 10 ° C ncua lub sij hawm kev nyab xeeb mus rau ntau tshaj 20 hnub. Rau kev fermentation hauv tsev, kev tswj qhov kub thiab txias tau pom zoo: 18-22 ° C rau thawj 3 hnub, ua raws li cov tub yees.

Cov khoom xyaw ua ntej ua rau muaj feem cuam tshuam rau qhov tshwm sim. Blanching cabbage rau 30 vib nas this txo cov ntsiab lus nitrate thawj zaug los ntawm 43%, txo qhov kawg nitrite ncov los ntawm 27%. Ntxiv cov vitamin C-nplua nuj cov khoom xyaw (piv txwv li, tshiab chili los yog txiv qaub slices) ntxiv txo cov peaks los ntawm 15% -20%.

3. Cov tswv yim siv kev nyab xeeb

Raws li kev sim cov ntaub ntawv, lub sijhawm fermentation tuaj yeem muab faib ua peb theem:

Lub sij hawm txaus ntshai (hnub 2-5):Nitrite qib siab tshaj Tuam Tshoj tus qauv kev nyab xeeb (20 mg / kg) los ntawm 2-3 zaug. Kev noj haus yuav tsum zam.

Lub sijhawm hloov pauv (hnub 6-10):Cov qib maj mam poob mus rau qhov ze-kev nyab xeeb.

Lub sijhawm nyab xeeb (tom qab hnub 10):Nitrite stabilizes qis dua 5 mg / kg, suav tias muaj kev nyab xeeb rau kev noj.

Cov txheej txheem optimizedtuaj yeem txo cov kev pheej hmoo:

Ib txoj kev gradient salting (2.5% thawj salinity, nce mus rau 3% tom qab) ua ke nrog inoculating 5% hnub nyoog brine shortens lub sij hawm txaus ntshai rau 36 teev.

Nquag nplawm kom paub cov pa oxygen boosted nitrite decomposition los ntawm 40%.

Rau kev sib tsoo high-nitrite, cov txheej txheem kho tau ua pov thawj zoo:

Ntxiv 0.1% vitamin C hmoov rau 6 teev txo nitrite los ntawm 60%.

Kev sib xyaw nrog qej tshiab (3% los ntawm qhov hnyav) ua tiav cov txiaj ntsig zoo sib xws.

Txoj kev tshawb fawb no tau lees paub tias muaj kev pheej hmoo hauv cov khoom noj fermented hauv tsev tuaj yeem kwv yees tau thiab tswj tau. Los ntawm kev nkag siab txog nitrite dynamics thiab ua raws li kev tswj hwm-xws li tswj 2.5% salinity, theem tswj qhov kub thiab txias, thiab cov khoom siv pretreatment-cov neeg siv khoom tuaj yeem muaj kev nyab xeeb rau cov khoom noj fermented. Khaws lub "fermentation cav" txhawm rau taug qab qhov kub thiab txias, lub sijhawm, thiab lwm yam kev ntsuas tau qhia, hloov cov kev coj ua hauv chav ua noj rau hauv kev paub txog kev tshawb fawb, kev paub txog kev pheej hmoo.