Sonke sibonile, ubisi ubisi olusuka ku-jug esedlule noma i-lemon juice efaka ubisi olufudumele. Lokho okwakulokhu kubushelelezi, ubisi obomvu buba buhlungu, bukhuni, futhi abukhiphi ngokuphelele. Kodwa ubisi oluphucuziwe akuyona into embi ngaso sonke isikhathi. Nakuba ngezinye izikhathi kubonisa ukuphangwa, kungase kube indlela yokukhiqiza ukudla okunomsoco okwedlula, njengokweshizi. Ubisi obuketshezi ngenxa yokuphendula kwamakhemikhali okulula okungafakwa endaweni yezizathu ezihlukahlukene.
Ake sihlolisise ezinye zalezo zizathu.
Ubisi obuketshezi
Ubisi lunamakhemikhali ambalwa, ikakhulukazi amafutha, amaprotheni, noshukela. Iprotheyini ebisi ngokuvamile imiswe esikhaleni se-colloidal, okusho ukuthi ama-molecule amancane amaphrotheni azungeze ngokukhululekile nangokuzimela. Lezi zimfucumfucu zamaprotheni eziphambanisayo ziphikisa ukukhanya futhi zinike ubisi ukubonakala kwayo emhlophe. Ngokujwayelekile lezi zinhlayiya zamaprotheni ziphikisana, zivumela ukuba zihambele ngaphandle ngaphandle kwe-clumping, kodwa uma i-pH yesisombululo sabo ishintsha, bangakwazi ukuheha ngokungazelelwe bese benza ama-clumps. Yilokho okwenzekayo lapho ubisi buhamba. Njengoba i-pH yehla futhi iba namandla, ama-molecule e-protein ( casein ) akhangane futhi abe "ama-curdles" asondela esisombululo samasondo ashubileyo. Lokhu kusabela okukhulu kwenzeka ngokusheshisa emazingeni okushisa okufudumala kunalokho okushisa okushisa.
Ubisi obisikiwe
Konke ubisi, ngisho nobisi olungagciniwe, luqukethe amabhaktheriya.
Njengoba amabhaktheriya ehamba ngokujabula ngempilo yawo, adla ushukela wemvelo ebisi, okuthiwa i- lactose . Njengoba begaya i-lactose, kunezinhlobo ezimbalwa zezinto ezikhiqizwayo, okufaka i-lactic acid. Uma inani le-lactic acid ebisi liqala ukwanda, i-pH yehla futhi ama-molecule we- casein aqala ukuqhuma.
Amazinga aphakeme e-lactic acid yilokho okunikeza ubisi obunamafutha obumuncu obumuncu.
I-Milk ne-Lemon Juice noma iViniga
Kuyinto evamile ukupheka ukubiza ijusi lemon noma uviniga ukuba wengezwe ubisi. Eqinisweni, ijusi lelamula kanye noviniga kunganezelwa ebisi njengengxenye yebhomishri ezincwadini zokupheka eziningi. Ngakho kungani lokhu kungabangela ukuthi ubisi luphele? Njengazo zonke izimo zamakhemikhali, izinga lokushisa lilawula izinga lapho ukusabela kwenzeka khona. Uma ufaka ujusi kalamula noma ubisi oluvuthayo ubisi olushisayo, luzovala ngokushesha, kodwa ukulifaka kubisi olubandayo ngeke lwenze ukuphendula okwesikhashana.
Lona ukusabela okufanayo okusetshenziselwa ukwakha ushizi olusha njenge-ricotta noma i- paneer . Ubisi buvutha ukushisa okhethiwe bese kuthiwa i-asidi (ilamula kalamula noma uviniga). Uma ubisi selukhahlela, amaprotheni aqinile abuye ahlulwe emagqumeni ahlanzekile futhi ahlolwe abe yindilinga. Kulesi simo, ukukhishwa kwe-curdling akuhlangene nalokho okushiwo yi-spoilage futhi, empeleni, kuyasiza kakhulu.
Ubisi kanye neKhofi noma iThee
Ngesinye isikhathi, ubisi olubandayo lufake ikhofi noma itiye lizophela. Lokhu kungasabeka njengoba ubisi oluboshiwe luvame ukubonwa njengobisi obusisiwe. Kulesi simo, kungaba yiqiniso elingamatshumi amabili. Ikhofi kanye netiye zombili zi-acidic, nakuba ngokuvamile kungenalo okwanele ukunqanda ubisi olusha.
Uma ubisi luphezu kwe-spoilage kanti amabhaktheriya akhiqize ezinye, kodwa hhayi i-asidi eyanele yokuvimbela ubisi obandayo, kancane kancane kwe-asidi eyengeziwe kusuka kwekhofi noma itiye, kanye nokushisa kwabo kungadonsela ubisi futhi kubangele ubisi ukuvala. Ubisi lungase lungabi khona ngokwanele ukuze kubangele iphunga elimnandi noma ukunambitheka, kodwa nje i-asidi ngokwanele kanye nokushisa ngaphezu kwalokho kungabangela ukukhishwa.