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cht khng ng v c

Cht khng ng Cht khng ng hu c khngcha N2

Cht khng ng hu c c

cha N2Cht khng ng Cht mu Khng c N 2 :

caramenhu c C N2 :

melanoidin2.1. ng sacaroza: quay cc : Dung dch ng c tnh quay phi. quay cc ring casacaroza rt t ph thuc vo nng v nhit . Do rt thun tin cho vicxc nh ng bng phng php phn cc.Cht kim, mui ca axit yu lm gim quay cc ca sacaroza

C12H22O11 + H2O C6H12O6 + C6H12O6sacaroza glucosa fructoza+66,50 52,5O - 93,0O

Hn hp c gc quay tri ngc vi gc quay phi ca sacaroza. Do phnng trn c gi l phn ng nghch o v hn hp gi l ng nghch o(chuyn ho).Tc dng ca kim: Phn t ng sacaroza khng c nhm hidroxyt glucozitnn khng c tnh kh. Khi tc dng vi cht kim hoc kim th, sacaroza tothnh sacaratTrong sacarat, hydro ca nhm hydroxyl c thay th bi kim loi. Nh vy

trong mi trng ny, c th coi sacaroza nh 1 axit yu. Phn ng to thnhsacarat ph thuc vo: nng ca dung dch, lng kim v lng sacaroza.Khi tc dng vi vi s thu c cc phc sacarat sau:

C12H22O11 . CaO. H2O : monocanxi sacaratC12H22O11 . 2CaO. 2H2O : dicanxi sacaratC12H22O11 . 3CaO. 3H2O : tricanxi sacarat

Hai dng monocanxi v dicanxi d ha tan trong nc, trong khi tricanxi rtt ha tan trong nc nn phn ng to thnh tricanxi sacarat c ng dng ly ng sacaroza khi r ng ca c ci.Trong mi trng kim, nhit cao, ng b phn hu to ra cc axit v chtmu..v...v.. Tc phn hu tng theo pH. nhit si (trong 1 gi) v pH =8 - 9, sacaroza ch b phn hu 0,05%. Nu cng nhit trn nhng vi pH l12 th s phn hu tng 0,5 % ( hnh 1.2)

S phn hu v to thnh cc sn phm c mu thng do nhng phn ng sau:C12H22O11 C12H20O10 C12H18O9 C36H50O25-H2O

-H2O-H

2O -2H

2O

Sacaroza(khng mu)

Izosacaran(khng mu)

CaramenlanEhrlich sacaran(mu m)

Caramelan

Caramelin(Schiff)

-19nH

2O

Humin

-H2O

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C36H48O24 C96H102O50 (C12H8O4)n Hoc (C3H2O) x

Cht mu caramen c coi nh l hp cht humin. l spolyme ho mc khc nhau ca - anhidrit.

- Tc dng ca enzim:Di tc dng ca enzim invertaza, sacaroza s chuyn thnh glucoza v fructoza.Sau di tc dng ca phc h enzim, glucoza v fructoza s chuyn thnhancol v CO2.

men ruC6H12O6 2 C2H5OH + CO2

glucoza hoc fructozaCht khng ng khng cha nit

2.2.1.1.Glucoza v fructoza . nhit cao v mi trng kim, glucoza v fructoza c th b phn hu v to

thnh mt s sn phm nh axit lactic, axit glucosacaric, axit formic, lacton.Nhng axit ny li kt hp vi vi to thnh mui ho tan. V vy khi dng vixu, hm lng mui can xi trong nc ma tng.

Trong mi trng kim, fructoza b phn hu nhiu hn glucoza. V vy,trong sn phm ng, lng glucoza thng nhiu hn fructoza. Tc dng ca axit:trong mi trng axit, ng kh n nh nht l pH=3 ch khng phi bng 7. Nhng trong mi trng axit v un nng, ng kh sto thnh oximetylfufurol v sau to thnh axit levulic v axit focmic. Tc dng ca cht oxi hoa: Glucoza ch tc dng vi brom trong mitrng axit v vi axit hipobromic trong mi trng kim. Phn ng tin hnh nh

sau: RCHO + Br2 + H2O RCOOH + 2HBrRCHO + HBrO RCOOH + HBr

Fructoza b oxi ho bi brm nhit cao v thi gian di hn so viglucoza. Tc dng ca nhit : Khi un nng nhit 160 - 170 0C , glucoza vfructoza b mt mt phn nc v to thnh glucozan v fructozan. Nu tip tcun nhit cao, CO2 s thot ra , cn li l than.

i vi fructoza , nhit 100OC, b phn hu nn nhit mtnc ca fructoza thp hn glucoza .

Axit hu c: Trong nc ma, cc axit hu c c th dng t do, mui hotan hoc khng tan , trong axit t do chim 1/3 lng axit chung.Ngi ta tm thy nhiu loi axit trong nc ma hn hp nh: axit.aconitic, a.xitric, a.malic, a.oxalic, a.glicolic, a.mesaconic, a.suxinic, a.fumaric. v..v.. trong hmlng a.aconitic gp 3 ln tng lng cc axit.V vy, ngi ta thu hi axit nydi dng canxi aconitat.Ngoi ra a.oxalic l thnh phn ng cn ch yu trongthit b bc hi v truyn nhit.Trong sn xut ng, axit c tc dng chuyn ha sacaroza

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Cht bo:Cht bo ch yu trong cy ma l sp. Sp thng to mt lp bao bc ngoi

cy ma. Trong sn xut ng ma, gn 60-80% sp theo b ma, phn cn li tnti trong bn lc.Cht khng ng cha nit:

hm lng cht khng ng cha nit bao gm:Anbumin v cc cht tng t 0,12%

Axit amin 0,20%Amit 0,07%NH3 _Nitrat 0,01%

Phn ln cht khng ng cha nit s t cy ma chuyn vo nc ma hnhp .ng v quan im k thut, vic chuyn c nh hng xu n chtlng sn phm. v gim hiu sut thu hi.Cht mu:

Cht mu trong cy ma c th chia lm 2 loi:- Cht mu c trong bn thn cy ma.- Cht mu sinh ra trong qu trnh sn xut ng.

* Cht mu c trong bn thn cy ma: ( phn ln l cht mu thc vt). Dip lc t a ( C55H72O5N4Mg). Dip lc t b ( C55H70O4N4Mg)

Dip lc t khng tan trong nc v dung dch ng nhng tan trongancol v kim. Do d loi ra khi lm sch nc ma.

. Xantophin : Mu vng, c cng thc C40H56O24 tan trong nc v dung dchng. N d b loi ra trong qu trnh sn xut ng.

. Caroten : Mu vng, c cng thc C40H56. Caroten khng tan trong ma vdung dch ng.. Antoxian: Thng gi nhm c mu xanh v tm d ho tan. Cht mu xanh

c tinh tan c to thnh t antoxianidin, glucoza v cc ng khc. Trongdung dch m c, antoxian chuyn thnh tm.Theo Zerban v Frelanen thanto xian thuc nhm poliphenol v chuyn thnh mu sm khi phn ng vi ccmui st. Trong giai on cacbonat, antoxian b loi hon ton. Phng phpsunfit ho ch loi c mt phn antoxian.

* Cht mu sinh ra trong qu trnh sn xut ng:. S phn gii ng nhit cao kt hp vi qu trnh ngng t gi l s

caramen ho . Cht mu l caramen.. Phn ng gia cacbonyl vi hp cht cha nhiu amin c gi l phn ng

Maillard v cht mu l melanoidin.. S phn gii ng nhit hi cao v trong mi trng kim.. S to thnh hp cht phc cht gia poliphenol v ion kim loi nng trc

ht l Fe. i vi sn xut ng thng gp cht mu melanoidin, caramen vpoliphenol + Fe.

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. Cht mu phn ln l hp cht hu c c ni i. Mun bin thnh chtkhng mu cn ph v ni i

Cht khng ng v c:Hm lng n ph thuc ging ma, ch canh tc v iu kin kh hu.

Cc cht v c ch yu trong nc ma hn hp l K2O, Na2O, SiO2,, P2O5, Ca,Mg trong K2O chim lng kh ln.Trong qu trnh lm sch P2O5 c tc dngtt. Nhng cht cn li u l nhng cht c hi trong sn xut ng. Kali vnatri l nguyn nhn to mt cui. Cc cht khc nh Ca, Mg, SiO2 l thnh phnch yu ng cn trong thit b bc hi v truyn nhit.

LY NC MAs dng hai phng php:

- p- Khuch tn.

Phng php p vn c s dng ph bin t my trm nm nay. Nguyn l

chung l x v p dp thn cy ma nhm ph v cc t bo ly nc ma.T hp mt s h my p hin nay trn th gii:

2K + 2R + 9R (12R)K + S + 2R + 9R (12R)

2K + S + 12R2K + 3R + 9R(12R)K: My bm ma.R: Trc pS: My nh ti.

My bm ma, my nh ti v p dp l cc b phn x l s b ma.