tìm hiểu phụ gia sử dụng trong sản xuất bánh.pdf
TRANSCRIPT
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VIN CNG NGH SINH HC THC PHM
TM HIU PH GIA S DNG TRONG SN XUT BNH
GVHD: Th.S H Xun Hng
SVTH: Trn Hong ip
H Th Phng Hiu
Ng Th Tn
Dip Kim Thu
Bi Th Thanh Thy
Lp: DHTP5LT
Thnh ph H Ch Minh, thng 3 2011
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M U
Ph gia l nhng cht khng th thiu trong ngnh cng nghip thc phm ni chung v ngnh
cng nghip
1. Bi cnh
sn xut bnh ni ring. N c th lm tng cm quan ca bnh, tng gi tr dinh dng hay
ko di thi gian bo qun. Cng vi s pht trin ca ngnh sn xut bnh th cc loi ph gia
c s dng cng a dng hn v liu lng s dng, tnh an ton cng c ch trng hn.
2. Mc ch
bi tiu lun Tm hiu v ph gia (tr ph gia to xp v to n) s dng trong sn xut
bnh ny, chng ti ch nghin cu mt vi ph gia c s dng trong ngnh sn xut bnh,
cc thng tin v n cng nh v vai tr ca n trong cng ngh sn xut bnh.
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CHNG 1 C S CHUNG
1.1.Tm hiu chung v bnh
1.1.1.Khi nim v bnh
Bnh l loi thc phm cha dinh dng cho c th v trong bnh c cha cc thnh phn
nh : gluxit, protit, lipit v c th b sung thm vitamin, cht khong, trong gluxit thng
chim mt phn ln trng lng bnh.
Bnh l sn phm n lin rt thun tin s dng,vn chuyn, bo qun.
Hin nay trn th trng ngoi cc loi bnh truyn thng, cc loi bnh mi pht trin
mnh m. Nhng loi bnh b sung thnh phn mi, b sung dinh dng cho tr em, cha
bnh
Th trng bnh Vit Nam c c im . Th nht: Nguyn vt liu u vo chnh ca
bnh bao gm bt m, ng, cn li l sa, trng v cc nguyn vt liu khc. Trong ,
nguyn vt liu phi nhp khu l bt m (gn nh ton b), v ng (nhp 1 phn), hng liu
v 1 s cht ph gia, chim t trng kh ln trong gi thnh. Chnh v vy s bin ng ca gi
bt m, ng trn th trng th gii s c nhng tc ng nht nh n gi thnh ca bnh. h
hai: Th trng bnh Vit Nam c tnh cht ma v kh r nt. Sn lng tiu th thng tng
mnh vo thi im t thng 8 m lch (Tt Trung thu) n Tt Nguyn n vi cc mt
hng ch lc mang hng v truyn thng Vit Nam nh bnh trung thu, bnh qui cao cp.
Trong khi , sn lng tiu thu bnh ko kh chm vo thi im sau Tt Nguyn n v ma
h do kh hu nng nng.. Th t mc tiu th bnh bnh qun ca Vit Nam hin nay vn kh
thp .
Vit Nam tr thnh mt th trng tim nng v tiu th hng lng thc thc phm
trong c bnh. C rt nhiu nh my ch bin bnh pht trin mnh nh Bibica, Hi H, Kinh
min Bc, Kinh min Nam .. Cc doanh nghip ny khng nh c thng hiu gn
vi cc dng sn phm ch lc ca mnh, cnh tranh kh tt vi hng ngoi nhp. [11]
1.1.2.Phn loi bnh
C rt nhiu cch phn loi bnh:
Da vo phng php lm n ta c :
-Bnh lm n bng phng php ha hc
-Bnh lm n bng phng php sinh hc
-
-Bnh lm n bng phng php c hc
Da vo m :
Bnh ti c m ln hn 15%. Bnh kh c m nh hn 5%.Ngoi ra c loi trung
gian : nu m nh hn 7% , hm lng bo ln hn 20% l bnh kh. Nu m ln hn 12% v
hm lng bo ln hn 5% xp vo bnh ti.
Bnh kh thi gian s dng ko di hn, d s dng , vn chuyn. Bnh ti thng n
trong ngy, thi gian bo qun ngn hn.
Da vo cu trc bt nho v phng php to hnh
Trong bi tiu lun ny s da vo phng php phn loi ny
-Cracker
Cracker lm t bt m c hm lng gluten rt cao, cn cht
bo cht ng rt thp. c im nguyn liu cho bt nho c tnh
cht c bit dai do n hi, khung gluten pht trin ti a. Phng
php to hnh cn, phn tm v ct. Cu trc sn phm gin cng.s
-Biscuit
Ngi ta cn chia ra 2 loi bnh biscuit mm v biscuit cng
Biscuit cng lm t bt m c hm lng gluten cao, cn cht
bo cht ng thp. c im nguyn liu cho bt nho c tnh cht
dai do n hi, khung gluten pht trin. phng php to hnh cn v
ct. Cu trc sn phm gin cng nhng khng bng cracker.
Biscuit mm lm t bt m c hm lng gluten trung bnh (thp hn t biscuit cng),
cht bo cht ng cng cao hn. c im nguyn liu cho bt nho c tnh cht t dai do
n hi, khung gluten pht trin hn ch hn. Phng php to hnh c . Cu trc sn phm
gin xp hn Cookies
-Cookies:
Cookies lm t bt m c hm lng gluten thp, cn cht bo cht ng rt cao. c
im nguyn liu cho bt nho c tnh cht khng c dai do n hi m bt mm, khung
gluten cng khng pht trin. Phng php to hnh lc ny l n
(nn). Cu trc sn phm mm xp .
Nhm bnh gm : craker, biscuit (mm v cng), cookies
c gi chung l bnh qui (biscuit) l cc dng bnh nng thng
-
kch thc nh. Nguyn liu bnh t bt m, ng, cht bo. Thng thng m t hn 4 %,
bao gi kn nn hn s dng ko di c th hn 6 thng. [3]
-Cake
Loi bnh ny thnh phn nguyn liu thay i rt a dng, cho
cu trc bt nho, phng php tp hnh v cu trc bnh cng nhiu
chng loi.
Nhm bnh c m ln nh : bnh bng lan..
Nhm bnh giu bo : bnh pa ..
1.1.3.Nguyn liu chnh cho sn xut bnh
Bt m
Bt m c ch bin t ht la m. La m c 2 loi l la m en v la m trng, do ,
ngi ta cng chia bt m thnh 2 loi. Loi bt m en: ch bin t ht la m en, thng dng
lm bnh m bng cch ln men lactic, c v chua, ch thch hp cho mt s khu v ca mt s
vng trn th gii.Loi bt m trng ch bin t ht la m trng. nc ta ch sn xut v nhp
bt m trng. lm cc loi bnh cng cn phi dng cc loi bt m trng. Tu theo cht lng
bt ta chia lm cc loi bt: thng hng, loi I, loi II v loi III. T bn loi bt trn cc nh
my sn xut s phi trn li thnh nhiu sn phm bt m vi cc thng hiu khc nhau bn
trn th trng.
Tu thuc vo ging la m sn xut bt m m bt m c thnh phn ho hc khc
nhau.Bao gm: Cht v c chim t 15 17%, ch yu gm nc v mui khong; cht hu c:
chim t 83 85%, gm lipit, glucid, protein, vitamin, sc t, emzim
Bt m thnh phn chnh cho hu ht cc loi bnh, nht l bnh u. N quyt nh rt
ln n cu trc bnh nng, cng v hnh dng ca bnh. Tnh cht ca bt m nh hng
ln bnh khc nhau cn ph thuc vo hm lng bo v ng trn chung vo khi bt nho.
C th c tnh ca bt m c ngi sn xut bnh ch trng chnh l s lng v cht lng
protein bt m, hay cn gi l gluten hnh thnh khi nho trn bt m vi nc. Nu cc loi
bnh lm t bt m c hm lng protein thp s cho khung gluten yu v gin . do bt c
protein chim 9% l tt nht v n tng qu 9,5% trong qu trnh cng ngh to ra. Bt nho
bnh craker ln men n ra nn cn bt mnh , vi protein hn 10,5%. Nu hm lng bt m
trng qu cao th khi nng bnh s lm hng cu trc bnh v bnh b xm mu. c cht
-
lng gluten xc nh ngi ta c th dng ph gia v k thut cng ngh iu chnh sao cho
ph hp. [4]
ng saccharoes
ng l thnh phn chnh v quan trng trong sn xut bnh. Ngoi chc nng to ngt,
ng cn nh hng n bin i cu trc v mi v cng nh cc nng cao cc thnh phn
khc.
i vi bt nho ln men, ng cung cp dinh dng cho men, gin tip lm tng kh,
v lm tng th tch bnh sau nng. ng ha tan hon ton hay mt phn ph thuc vo hm
lng nc. Nu hm lng ng cao bnh s cng. Kch thc tinh th ng lm tc
hon tan ng khi bt nho m ln trong l nng cng nh hng n s ko gin khi bt khi
nh hng n v b ngoi v cng gin ca bnh.
Nu ng qu nhiu, t bo ha th n lm gim lng nc cn thit trong bt nho.
ng s thay i im to gel ca tinh bt cao hn , bt nho cn nhiu thi gian tng nhit
trong l. Nu ng c pht trn b mt bnh , khi nc n chy ra v lm b mt bnh bng
lng hp dn
ng cn l thnh phn chnh ca nhn bnh nh nhn socola, mt, caramen.
ng l disaccharide cu to t hai phn t fructose v glucose. Nu ng b thy
phn s thnh ng kh , ng nghch chuyn. cc monosaccharide phn ng mailard vi axit
amin khi nng bnh cho mu v mi , thng th 10-20 dng trong bt nho s chuyn ha
thnh ng kh.
Fructose ngt hn ng , fructose v glucose u cho cm gic mt khi tan trong ming.
hai loi ng ny u c gi tr cho bnh.[4]
Mch nha
Mt tinh bt hay cn gi l mch nha, l sn phm trung gian ca qu trnh thu phn
tinh bt bng acid hay enzim amylase. Thnh phm mt tinh bt gm c: glocose, frutose,
mantose, dextrin. Thnh phn tng cht thay i tu thuc nhiu vo ngun tinh bt thu phn,
cch thc thu phn v iu kin thu phn.
Hm lng ng glucose trong mch nha khong 25 30%. Glucose l ng kh, tn
ti di dng v nh hnh, c tnh ht m, kh nng ht m tng theo nhit .
Fructose cng l ng kh, d b ln men bi nm men. Fructose c ngt cao nhng chim
hm lng thp trong nm men.Mantose l mt disaccharit, cu to gm hai gc a_glucose.
-
Mantose t ht nc, phn hu 900 1000C. Hm lng ng mantose trong mch nha khong
10 15%.Dextrin thuc nhm polysaccharit, c v ngt tng i thp v thay i tu thuc vo
di ca mch polysaccharit. Dextrin c khi lng phn t ln nn c nht cao v c tnh
dnh. Dextrin c kh nng to keo tt, hm lng dextrin trong mch nha khong 30 45%.
Cht bo
Cht bo dng cho bnh nh ph trn b mt bt nho, lm lp nhn kem hay bao ngoi
nh socola. n c nh b v margarin cn cho mi v c bit.
Cht bo cng th hin chc nng cu trc cho bt nho. Trong qu trnh trn bt, nc
hay mui ha tan tng tc vi protein bt m to ra khung gluten dai v n hi. Cht bo ngn
cn s to khung gluten , khi n bnh sau nng t cng, mm hn v thm ch chy ra trong
ming. Hm lng bo cao rt t gluten c hnh thnh, s ht nc trng n ca tinh bt
cng gim v v th cu trc mm. khi bt b chia vn d dng.
Cht bo cn gi t bt n ra v to cu trc khi nng. Cc nghin cu cho thy khi
nng bnh, cht bo ngn kh di chuyn n v bnh giai on nhit 37-58 oC. Cht bo
khin bt nho tr nn mm hn v trc khi ht nc trng n tinh bt ly nc ca gluten
lm cho n chc v n hi hn. S n nh ny lm th tch bnh vng hn v cu trc tt hn.
Tnh cht chc nng ny xut hin loi bnh hm lng bo tht.
Trng
Tu theo tng loi sn phm bnh khc nhau, ta c th s dng trng g hoc trng vt.
Hin nay, sn phm trng trn th trng rt a dng: trng ti, bt trng nguyn, bt lng
trng trng (albumine trng), bt lng trng.
Qu trng ti c trng lng t 43 54 g, gm lng trng c bao bn ngoi, lng
bn trong. Trng ti sau khi c ng ho, c c v sy kh s thu c bt trng. Nu ta
phn ring lng v lng trng, c c v sy kh s thu c bt lng trng trng kh v bt
lng kh.
Trng cho vo bnh ko gip lm tng gi tr dinh dng, gi tr cm quan ca sn phm
do trng c gi tr dinh dng rt ln. Ngoi ra trng cn to gel, to bt, lm cho bnh ti xp.
Thnh phn leucithin trong lng trng l cht to nh, c kh nng nh ho cht bo tt, gip
cho bnh c cu trc bn vng hn.
Cc thnh phn khc
-
Trn y gii thiu cc thnh phn chnh cho cng ngh sn xut bnh. Trong phn
ph gia thc phm s c phn tch su hn ni dung trnh by sau y.
1.2.Tm hiu chung v ph gia thc phm
1.2.1.Khi nim ph gia thc phm:
Ph gia thc phm l nhng cht t nhin hoc ha hc khi cho thm vo thc phm theo
mun tng thm gi tr dinh dng , ko di thi gian bo qun hoc lm tng tnh cm
quan ca thc phm .. gi chung l ph gia thc phm. Nhn chung cht ph gia thc phm c t
hoc khng c cht dinh dng , bn thn n khng c tiu th thng thng nh mt loi
thc phm, vic b sung chng vo thc phm l gii quyt mc ch cng ngh trong sn
xut ch bin, bao gi, bo qun, vn chuyn thc phm nhm ci thin mt s kt cu hoc c
tnh k thut ca thc phm . [5]
Trong qu trnh sn xut thc phm c khi s dng cc cht h tr k thut . y l cc
ch phm t nhin hoc tng hp ha hc khng phi thc phm. c a vo thc phm mt
cch c thc hin nhng mc ch k thut nht nh. Khng c lu li trong thc phm
sau khi thc hin xong chc nng k thut. [5]
Ph gia cho bnh thuc nhm ph gia thc phm ,m nhim cc tnh cht chc nng
to cho bnh cc tnh cht sn phm mong mun. khng phi tt c cc loi ph gia u c b
sung vo bnh . Nhng ngnh cng nghip sn xut bnh lun cn phi trn ph gia t mc
ch cng ngh m cch ch th cng khng mang li c.
Cng vi s pht trin ca cc loi bnh truyn thng v bnh mi, cc loi ph gia thc
phm ngy cng pht trin phong ph hn.
1.2.2.Phn loi ph gia thc phm :
Phn loi ph gia theo nhm chc nng
(Theo quyt nh s 3742/2001/QD-BYT 31/8/2001 ca B Y t)
-Cc cht iu chnh axit
-Cc cht iu v
-Cc cht n nh
-Cc cht bo qun
-Cc cht chng ng vn
-Cc cht chng oxi ha
-Cc cht chng bt
-
-Cc cht to phc kim loi
-Enzym
-Cc cht kh y
-Cc cht lm bng
-Cc cht lm m
-Cc cht lm rn chc
-Cc cht nh ha
-Phm mu
-Cc cht to bt
-Cc cht to phc kim loi
-Cc cht to xp
-Cht x l bt
Phn loi ph gia thc phm theo mc ch
Ty theo mc ch ngi ta phn loi ph gia thc phm theo mc ch thnh cc nhm chnh
sau :
-Ph gia dinh dng
-Ph gia bo qun thc phm
-Ph gia tng gi tr cm quan thc phm
-Ph gia s dng ch bin c bit
Cch nhn bit ph gia v s dng :
Ch E..: K hiu xc nh loi ph gia dng trong thc phm, cc ch s tip theo l tn ph gia
-Cc ph gia chng vi sinh vt : E200-290
-Cc cht chng oxi ha : E300-E320
-Cc cht to mu : E100-E180
-Cc cht to v :E621 l bt ngt
-Cc cht gy nh tng: E322-E494
Ph gia thc phm c s dng phi nm trong qui nh ca B Y T. thng xuyn
cp nhp danh mc bit c s thay i cc loi ph gia. Ph gia phi t yu cu tiu chun
tinh khit nht nh. i vi sn phm xut khu , ph gia tun theo cc qui nh quc t nh
FAO (t chc lng nng th gii ) v WHO (t chc y t th gii).
-
S dng ph gia theo liu lng ng k thut t mc ch k thut v an ton v sinh thc
phm. [5]
CHNG 2 CC LOI PH GIA TRONG SN XUT BNH
2.1 Ph gia bo qun
a phn ph gia bo qun trong cng ngh sn xut bnh l ph gia chng oxi ha.
Ph gia chng oxi ha l nhng cht c tc dng lm chm s i thiu ca cht bo gy ra bi qu
trnh oxi ha. Chng c s dng trong cng ngh sn xut bnh bch quy chng li qu
trnh oxi ha cht bo, ngn nga s to thnh cc gc t do v ngn cn qu trnh lan truyn s
oxi ha t ng. Cht chng oxi ha thng dng nht trong qu trnh sn xut bnh bch quy l
BHA (butylated hydroxyanisole), BHT (butylated hydroxytoluene), propyl gallate v TBHQ
(tertiarybutylhydroquinione). Ngoi ra, mt s bng chng cho thy rng sucrose trong bnh
bch quy hot ng nh cht chng oxi ha n ha.
Cht chng oxi ha l nhng cht c lin quan cht ch vi cc loi thc phm c cha cht
bo. Chng thng c cho vo giai on tinh luyn du hn l cho trc tip cng on nho
bt v nu cho cht chng oxi ha trong cng on ny nhn chung s khng mang li s phn
tn tt v cht bo c th bt u b oxi ha. [7]
2.1.1 Butylat hydroxy anisol (BHA)
- Tn ting Anh: Butylated Hyroxylanisole
- INS: 320
- ADI: 0 0.5
- ML (Maximum level):
+ Cc loi bnh nng: 200
+ Bnh c sa, trng: 25 [2]
BHA l tinh th mu trng, i khi hi vng, c mi thm thong c trng.
BHA khng tan trong nc m tan trong du, m ethanol
v cc loi dung mi hu c khc. [5]
-
BHA c hiu lc i vi cht bo c ngun gc t ng vt nhng li mc tng i
i vi cht bo c ngun gc thc vt. N c kh nng chng li s oxi ha cht bo rt tt t
giai on nho bt to thnh bt nho cho n giai on nng bnh. [7]
2.1.2 Butyl hydroxy toluen (BHT)
- Tn ting anh: Butylated Hyroxytoluen
- INS: 321
- ADI: 0 0.3
- ML (Maximum level):
+ Cc loi bnh nng: 200
+ Bnh puting c sa, puting go hoc puting l t bt
sn: 90[2]
BHT l cht rn mu trng, dng tinh th, khng tan trong
nc, tan trong cht bo, b tn tht di tc dng ca nhit.
BHT c tc dng chng oxy ha km hn BHA. iu ny c
gii thch l do cu to ca n cng knh hn BHA. [10]
2.1.3 Propyl gallat (PG)
- Tn ting anh: Propyl gallate
- INS: 310
- ADI: 0 1.4
- ML (Maximum level):
+ Bnh puting: 90
[2]
-
Propyl gallat l tinh th mu trng hoc trng kem, khng mi, c v hi ng; t tan trong
cht bo nhng li d tan trong nc, ethanol, ater, propan 1,2 diol. [5]
Propyl gallat nhy vi nhit, b phn hy nhit 1480C (nhit trung tm ca bnh bch
quy trong sut qu trnh nng dt khong 1050C). [7]
2.1.4 Tert butyl hydro quinon (TBHQ)
- Tn ting anh: Tertiary butylhydroquinone
- INS: 319
- ADI: 0 0.7
- ML (Maximum level):
+ Bnh puting: 200
[2]
TBHQ l cht chng oxi ha c hiu qu nht cho hu ht cc loi cht bo, c bit l cht
bo c ngun gc t thc vt. N c th duy tr tnh cht c trng cho bnh. [7]
2.2 Ph gia lm tng gi tr cm quan
Cm quan l yu t cht lng quan trng hng u ca sn phm thc phm. Do ,
phn ln cc ph gia thc phm l nhm tng gi tr ny. Cc yu t cm quan bao gm mu sc,
mi v, cu trc gip cho sn phm thc phm c sc hp dn v gi c tnh cht trong
thi gian di trong iu kin sn xut cng nghip.
i vi cc sn phm bnh, yu t cu trc ( n hi, mn, xp, mm) l c
bit quan trng. N gip cho ngi s dng cm nhn c mi v sn phm tt hn.
2.2.1. Cc cht iu chnh acid (acidity regulators) [9]
2.2.1.1. Acid citric
Trong t nhin c nhiu trong qu chanh, hin ti, dng dng ph bin l sn
phm tng hp sinh hc. V chua ca n hp khu v nn c ng dng rng ri trong cng
ngh thc phm. Ngoi ra, acid citric cn th hin hot tnh chng mt s nm mc v vi khun.
-
Acid citric dng trong thc phm phi dng kt tinh khan hoc ngm mt phn t nc,
khng mu, khng mi. Loi khan phi cha khng t hn 99,5% C6H8O7, 1g tan trong 0,5 ml
nc hoc trong 2 ml ethanol.
Vi liu lng cao (1380 mg/kg th trng) trn ch khng thy hin tng tn thng
thn. Vi chut cng trng, liu lng 1,2% trong thc n hng ngy, khng nh hng n
mu, khng thy mt tc ng nguy hi g n cc b phn trong c th, khng nh hng n
s sinh sn m ch hi nh hng n rng so vi chut i chng.
Liu lng s dng cho ngi: 060 mg/kg th trng.
2.2.1.2. Acid tartaric
Acid tactaric dng trong thc phm phi dng bt khng mu, trong sut, khng mi,
v acid, 1g tan trong 0,8 ml nc hoc trong 3 ml ethanol. Sau khi sy kh n trng lng
khng i 105C khng cha t hn 99,5% C4H6O6. V chua ca n mnh hn axit citric gp
1,2-1,3 ln.
Vi liu lng cao t 4000 mg/kg th trng, lm cht cc loi ng vt th nghim: chut,
ch, th. Vi liu lng thp hn (khong 1000 mg/kg th trng), c th nh hng n nit
huyt, gy cht sau 90 ngy (th nghim trn ch).
Th nghim c tnh di ngy, vi cc liu lng 0,1%, 0,5%, 0,8%, 2% acid tactric,
khng thy nh hng g n s pht trin, n s sinh sn hoc tn thng cc b phn ca c
th (1,2% tng ng vi 600 mg/kg th trng).
Acid tactric hu nh khng chuyn ha g trong c th con ngi, 20% c thi qua
nc tiu, tiu phn cn li b ph hy trong rut bi tc dng vi sinh vt.
Liu lng s dng cho ngi: 03 mg/kg th trng.
tan ca mt s acid hu c trong nc:
-
Acid g/100g nc
Tartaric 19
Malic 58
Citric 64
Acid citric v tartaric cho v chua gt nhng mau phai. Acid malic c v chua thp hn
nhng lu phai hn. Acid lactic c v nht nht nhng lm cho sn phm c cm gic trn.
2.2.2. Cc cht iu v (flavour enhancers)
2.2.2.1. Natri clorua [9]
Vai tr
- iu v
- Tng bn v tnh ht nc ca gluten
- Gim s pht trin ca men (proteolytic enzymes)
Qui cch s dng
- Dng t 1 -1,5% so vi bt
2.2.2.2. Monosodium glutamat-MSG (E 621)
Natri glutamat l mui ca acid glutamic c dng bt tinh th trng, c v mn, hi ngt,
trng lng phn t 147,13g/mol. Natri glutamat ha tan nhiu trong nc, 20C, trong 100g
nc ha tan c 136g natri glutamat tinh khit.
V ca natri glutamat c th cm thy khi pha long ca n trong nc l 1/3000. Khi
sn phm c axit thp: pH = 5-6,5 th v ca natri glutamat nhn thy r rt nht. Trong mi
trng axit cao, pH 4, v ca n mt i.
Glutamate khng ht m t khng kh v khng thay i hnh dng bn ngoi hoc cht lng
trong sut qu trnh bo qun. N khng b phn ly bi qu trnh thy phn thng thng hoc
trong qu trnh ch bin. Trong iu kin acid (pH = 2,24,4), nhit cao, mt phn
glutamate b dehydrate ho v chuyn thnh 5-pyrolidone-2- carboxylate.
-
Tng t nh trng hp cc acid amin khc, chng s tham gia phn ng Maillard cng vi
ng kh trong iu kin nhit cao.
V c trng ca glutamate: umami l do cu trc lp th ca chng. Thuc hp cht
glutamate th c nhiu loi khc nhau vi cu trc ho hc khc nhau gy nn nhng tnh cht v
khc nhau v c trng cho mi loi.
Dng L ca - amino dicarboxylate c 47 carbon mang nhng tnh cht v gn nh nhau l L-
glutamate.
Nhng hp cht c dng threo v nhm hydroxy v tr nh DL-threo-
hydroxyglutamate, to v mnh hn cc hp cht c dng erythro v nhm hydroxy v tr.
L homocystate c nhm SO 3 H v tr ca phn t L glutamate gy v umami.
-
Cc mui aminoacid khc c nhng tnh cht cm quan tng t l ibotenate (hnh IV),
tricholomate (hnh V) v L-thianine (hnh VI). Ngc li, -methyl-L-glutamate (hnh VII),
nguyn t -hydrogen c thay th cho mt nhm methyl, th khng c v; v pyrrolidone
carboxylic acid (hnh VIII), c to do s mt nc t NH2 v nhm-carboxylic ca L-
glutamate, c v chua.
MSG c s dng nh l cht iu v, lng MSG s dng trong cc sn phm khc
nhau th khc nhau, nhng nhn chung th chng ch trong khong 0,05 0,8% trng lng thc
phm a vo iu v l tt nht. N kch thch s n ngon dn n tiu ho thc n tt, nng
cao gi tr dinh dng cho thc phm. Nhng bn cnh , n cng ng vai tr cn thit cho s
trao i cht trong c th. N c tng hp trong c th p ng cc yu cu ca c th. Tuy
khng cn thit phi cung cp chng trong ba n, v chng thuc loi acid amin thay th, nhng
chng li cn mc gp hai ln lng cn thit cho c th chng ta: chng cung cp ngun nit
quan trng v hot ng b sung hoc bo ton cc acid amin chnh.
Glutamate c tnh c cp tnh rt thp. Nm 1987, Hi ng cc chuyn gia v ph gia
thc phm v t chc Nng nghip ca Hip hi cc quc gia v T chc Sc kho th gii
-
(FAO/WHO) xem xt v a ra s tn ng v s an ton ca glutamate, lng glutamate cho
php vo c th con ngi mi ngy ADI l khng gii hn.
2.2.3. Cc cht to gel (gelling agents)
Cc ph gia ny c s dng nhm nh hnh cu trc ca sn phm bnh ko.
Gum v agar l hai cht to gel c s dng rng ri nht trong cuc sng ni chung v cng
ngh sn xut bnh ko ni ring. Mi loi cht to gel v cht to bt u c vai tr ring, to
cho thnh phm nhng cu trc v tnh cht ring bit:
2.2.3.1. Carrageenan
y l mt sn phm thng mi c s dng trong nn cng nghip sn xut bnh ko
nhm to h gel cho sn phm ko do, sn xut bnh flan (s dng - carrageenan), sn xut
ko scla... Carrageenan l nhng polyisaccharide c chit t cc loi to bin c mu .
Thnh phn ha hc ca carrageenan l chui cc ng D-galactose c cha gc sulphate lin
kt vi nhau bng lin kt 1-3 v 1-4. Carrageenan c cc dng nh sau: - carrageenan, -
carrageenan, -carrageenan, -carrageenan, -carrageenan.
2.2.3.2. Gelatin
Gelatin c s dng nhm to h gel cho sn phm bnh ko.
Gelatin c sn xut t da v xng ca ng vt. Ngi ta s dng ngun protein
collagen c trong xng v da, kim ha hoc axit ha nhm thu c gelatin.
Kh nng to gel ca gelatin ph thuc nhiu vo pH ca mi trng. Trong cng nghip
sn xut, thng thng, ngi ta ha tan gelatin nhit di 800C, v nu nhit qu cao,
gelatin s b bin tnh v gim kh nng to gel. Gelatin c cho vo thc phm trc khi cho
thm bt k cc thnh phn axit no.
2.2.4. Cc cht to bt (whipping agents)
Cc cht to bt nh c tnh nng nh cc cht hot ng b mt, c tc dng to v gi
cc bt kh trong cu trc sn phm bnh ko.
Hu ht, cc cht to bt trong cng ngh sn xut bnh ko ch yu l protein.
-
Cc protein c cu trc mt trt t hay gp khc s c kh nng to bt tt hn cc
protein c cu trc hnh cu. Tnh cht k nc v a nc ca cc thnh phn trong protein c
nh hung nhiu n kh nng to bt ca chng.
Cc yu cu i vi mt cht to bt : tan trong pha lng, c kh nng gim sc cng b mt
lng kh v c th bin i to nn cu trc, n nh cu trc cho h.
Cc thnh phn to bt lm tng xp cho sn phm. Trong cng nghip bnh ko, cht to
bt c s dng rt rng ri, trong sn xut ko do th cht to bt l khng th thiu trong qu
trnh sn xut.
2.2.4.1. Albumin ca trng
Dng tinh th, c sn xut t lng trng trng g. Lng trng trng c lm kh,
nghin, to nn tinh th rn.
Albumin ca trng l mt cht to bt c s dng rng ri v kh nng to bt ca n.
Ngoi ra, albumin rt d bin tnh theo nhit . Albumin c kh nng to bt rt tt, sn phm
thu c khi s dng albumin c cht lng tt hn khi s dng cc cht to bt khc. Chng
nhng th, albumin ca trng li c gi tr dinh dng hn so vi cc cht to bt khc.
2.2.4.2. Protein sa
Protein trong sa c phn thnh hai loi: protein c thu phn v ch phm
protein (modified protein).
Ta s dng cc protein b bin tnh lm cht to bt trong cng ngh sn xut bnh ko. Cc
protein bin tnh c cc tnh cht ca cht hot ng b mt, ho tan trong nc v c nh bt.
Hyfoama l protein sa c s dng lm cht to bt ph bin nht.
Thng thng, ngi ta s dng hyfoama vi hm lng 0,3-0,5% khi lng. Khi s dng
hyfoama, khng cn phi ngm cho trng ln trc .
2.2.4.3. Protein u nnh
Protein u nnh bin tnh c th s dng lm cht to bt. Protein ny c trch t du
u nnh, qu trnh ny cn s c mt ca h enzym nhm lm bin tnh protein. Protein u
-
nnh c kh nng to bt rt tt, cc tnh cht tng t nh albumin trng, do , c th s dng
protein u nnh thay th cho albumin.
Trong sn xut, protein u nnh khng cn phi ngm trc . Nn ha tan protein u nnh
vi nc theo t l 1:2 1:3. Protein ny tng i bn nhit, bn vi s c mt ca cht bo, tuy
nhin, chng s khng ho tan nu nhit qu cao. Bt ca protein u nnh kh bn vi thi
gian. Vn duy nht l protein u nnh to ra thnh phm mm hn so vi sn phm dng
albumin trng.
2.2.5. Cht to ngt nhn to (artificial sweeteners)
2.2.5.1. Saccharin (E 954)
y l cht ngt nhn to u tin c tng hp M vo nm1879 do hai nh ho hc
Remsen v Fahlberg v mi cho n nm 1900 mi c a vo sn xut thc phm nh mt
cht ph gia. Chu u, vic s dng saccharin ch tng nhanh hai thi k chin tranh khi
lng ng thiu ht nghim trng.
Saccharin l tn chung ch saccharin, saccharin natri v saccharin canxi. Saccharin c cng
thc phn t l C7H5NO3S v c cng thc cu to nh sau:
V bn cht ho hc th n l 1,2 benzisothiazol 3(2H) 1 1,1 dioxide v mui natri
hay canxi ca chng.
Saccharin c sn xut theo hai phng php: toluen v acid chloro-sulfomic hay t
anthranilate.
Saccharin v saccharin natri khng tn ti trong t nhin. Saccharin tn ti dng tinh
th mu trng. Chng chu c c nhit cao v nhit thp. Chng tan c trong nc v
trong ethanol.
-
Saccharin c ngt gp 300 ln so vi saccharose cng mt nng saccharin trong
nc. Saccharin v mui ca chng rt bn trong bt k cc iu kin sn xut v chng cng c
th tn ti rt lu trong pH < 2.
Saccharin hon ton khng to ra nng lng, rt kh hp thu vo ngi v mt phn
chng c thi ra theo ng nc tiu. Theo quy nh ca FAO/WHO, liu lng cho php s
dng l 2.5mg/kg th trng.
2.2.5.2. Cyclamate
Cyclamate natri c tng hp vo nm 1937 v ln u tin c sn xut cng nghip
vo nm 1950 ti M. Cyclamate l tn chung ch acid cyclamic, cyclamate natri v
cyclamate canxi.
Cng thc phn t C12H24CaN2O6S2.2H2O.
Cyclamate hon ton khng th tm thy trong thin nhin. Cyclamate c tng hp t
cyclohexylamine bng cch sulfonate ha cht khc nh: acid chlorosulfonic, acid sulfamic; sau
c trung ho bi hydroxyt.
Cyclamate c ngt gp 30 ln ngt ca ng saccarose, rt bn vi tc nhn nhit
v c th chu c khong nhit kh cao. Cyclamate d tan trong nc v c th c s
dng nh cht to ngt khng cha nng lng trong thc phm.
Khi kt hp vi saccharin theo t l 10 :1, s ci to ngt tt hn.
Cyclamate hp th qua ng rut v mt phn cyclamate s chuyn thnh
cyclohexylamine do vi sinh vt trong rut, mt phn cyclamate s tham gia vo qu trnh trao i
cht khong (khong 60%) v lng ny cng s c chuyn ti a to thnh
cyclohexylamine.
Theo khuyn co ca FAO/WHO liu lng cho php l 11mg/kg th trng.
-
2.2.5.3. Sucralose
y l mt loi cht ngt c tm ra nm 1976, c bn nhit cao, c mi v c
ngt gp 600 ln ngt ca saccharose v c s dng rt rng ri trong ngnh cng nghip
thc phm ni chung v ngnh cng nghip bnh ko ni ring.
2.2.6. Hng liu v phm mu (flavours and colours)
Cht to mu, to v c thm vo sn phm ko khng phi nh la ngi tiu
dng v cht lng v dinh dng ca sn phm. Chng khng ch c thm vo duy tr
hnh dng v mi v trong thi gian s dng lu di ca sn phm, hay to ra n tng v gi
c cao ca thnh phn hay gi v nhng thnh phn khng tn ti trong sn phm. Tuy
nhin, chng c thm vo nh l nhng cht ph gia cho nhng sn phm nhiu ng v
bo, t x chng c ngon hn, hp dn hn. V nhng chuyn gia khng nh rng iu ny
dn ti cht lng dinh dng thp, su rng v nhng bnh lin quan n ch n ung.
Mt mi v tt s kch thch vic tit nc bt : y l chc nng quan trng nht ca mi v.
Cng vi vic gy n tng v v, hng, hnh dng v mu th cm gic sng khoi cng c
gi ln khi s dng.
2.2.6.1. Phm mu
C th dng mu t nhin hay tng hp: dng mu cochineal (chit t xc cn trng),
vng saffron t hoa cc vng, caramel t phn ng caramel ho ng.
Trong biscuit th mu caramel thng l mu nu do dng nhiu ng hay dng bt
cacao lm sm mu b mt sn phm.
Cc loi mu:
- Tng hp-nhng khng ging mu t nhin
-
- Tng hp-ging vi mu t nhin
- T nhin-c c t cy v ng vt
Mu
E120 Carmine T nhin
E122 Carmoisine Tng hp
E124 Amarath Tng hp
E127 Erythrosine Tng hp
Mu vng v mu cam
E100 Curcumin T nhin
E101 Riboflavin (vitamin B2) Tng hp, t nhin
E102 Tartrazine Tng hp
E104 Quinoline Tng hp
Mu xanh ti (Green)
E110 Chlorophyll T nhin
E141 Chlorophyll derivative T nhin
E142 Green S Tng hp
Mu nu
E150 Caramel T nhin
2.2.6.2. Hng liu
Cc cht c mi thm thng l cc tecpen, setquitecpen, ru, ester, phenol, aldehyt
-
Hng liu s dng trong bnh ko rt a dng, ty thuc vo loi sn phm, c th s
dng cc loi hng liu t nhin, trch t cc loi hoa, qu t nhin, hay c tng hp ho
hc, sinh hc. Hng c th cho vo khi bt nho trc khi nng, ph hay phun mi sau khi
nng, cho vo cc phn khng nng nh nhn, mt, kem
Cc cht c mi t thng gp trong t nhin l tinh du v nha. Tinh du v nha
thuc nhm hp cht izoprenoid. Nhm hp cht izoprenoid bao gm rt nhiu cht: ngoi tinh
du v nha cn c steroid, carotennoid. Cc cht thuc nhm izoprenoid c c tnh chung l
khng ha tan trong nc m ha tan trong cc dung mi hu c. Mt s hng liu t nhin :
Nhm Tn Ngun gc
Monoterpen
Linalon Trong hoa lan chung, qut v trong cy mi
Geraniol Trong tinh du khuynh dip
Xitrolenol Trong tinh du hoa hng, phong l v cc tinh du khc
Xitral Trong tinh du h cam qut v trong cc tinh du khc
Limonen Trong nha thng, trong tinh du cam chanh v th l.
Camphen Trong tinh du chanh, tinh du h hoa trc bch, tinh
du linh sam v trong cc tinh du khc
Pinen Trong tinh du thng
Sesquiterpen
Xinhiberen Trong tinh du gng
Humulen Trong tinh dau houplon.
Fernezol Trong tinh du cam, chanh, hoa hng v trong mt s
tinh du khc.
Nerolidol Trong tinh du ca hoa cam v trong nha thm Peru.
Xantonin Trong h thu du
-
Diterpen Acid abietic Trong nha thng
Triterpen
Squalen Trong cht bo ca gan c mp, cng nh trong cc c
khc
Acid
masticadienic
Mt vi cht ha hc tng hp c s dng to mi :
Cht thm Cht bo
Nhn benzen D vng Mch vng Mch thng
Phenol
Ether
Acetal
Carbonyl
Acid carboxylic
Ester
Lacton
Hp cht sulfur
Thiazole
Furan
Pyran
Thiophene
Pyrazine
Imidazole
Pyridine
Pyrrole
Oxazole
Thiazole
Lactone Hydrocarbon
Alcohol
Carbonyl
Acid carbocilic
Ester
Isoprenoid
Hp cht sulfur
Hp cht nit
-
Hng c trng cho mt loi hoa qu no (trong sn phm c hng tri cy) thng l
mt hn hp rt nhiu cht, to mi tng t, ngi ta thng pha ch hn hp gm nhiu
hp cht vi nhau, trong thnh phn c th c cc tinh du t nhin v nhn to.
i vi tinh du tng hp, cho php s dng cc ester: amyl acetat, amyl butyrat, etyl
butyrat... cc cht thm khc nh: aldehyt benzoic, vanilin, mentol, nha thm pru, xitrol,
cumarin, heliotropin
Cc cht thm tng hp nhn to th thng bn nhit hn cc cht thm t nhin nn
dng n thm vo cht thm t nhin th mi thm s c tng cng v bn vng hn. Nng
ca cc cht thm tng hp thng thng l mnh hn cc cht thm t nhin nn cng
mi thng mnh hn.
Ngoi ra bng phng php tng hp hu c, ngi ta c th thu c cc hp cht hon
ton mi l, gip lm phong ph mi thm cho cc sn phm thc phm khc nhau.
Cht mi l mt phn ca thc phm, v vy chng phi khng c v an ton. Cc cht
mi s dng trong cng nghip thc phm phi tha mn cc yu cu sau:
Thuc nhm nhng cht c cu trc n gin v c quan h gn nhau. Mt vi cht
trong s ny c nghin cu v chng minh khng c c tnh ng k liu lng
cao hn liu lng trong khu phn hng ngy ca con ngi.
c bit n hoc c tha nhn l c chuyn ha n cc sn phm an ton hoc
c bi tit bi nhng c ch c xc nh.
c s dng liu lng rt thp v xc nh trong khu phn hng ngy.
Cc cht mi cha c ng dng v thiu mt vi yu t bo m nh: c cu trc phc
tp, khng bnh thng hoc khng c bit n, khng c mi lin h vi nhng cht
c chng minh tnh an ton khi s dng hoc nhng cht c kho st c tnh,
khng c tha nhn l c chuyn ha an ton khi vo c th, phi dng liu lng
cao trong khu phn hng ngy.
Cn ch c tnh ca bn thn hng liu v c tnh ca cc dung mi ha tan hoc ca
cht ph gia trong cc cht thm thng phm.
S dng khng hn ch:
-
Ethyl acetat: 0 25 mg/kg th trng
Ethyl butyrat: 0 15 mg/kg th trng
Ethyl vanilin: 0 - 10 mg/kg th trng
-undeca lacton: 0 1,25 mg/kg th trng
Vanilin: 0 10 mg/kg th trng
S dng c iu kin:
Izo amyl butyrat: 0 5 mg/kg th trng
Xinamaldehyt: 0 1,25 mg/kg th trng
Xitral: 0 1 mg/kg th trng
Eugenol: 0 5 mg/kg th trng
2.2.7. Sa c s dng nh mt ph gia trong cng ngh sn xut bnh ko
Sa l mt trong nhng thnh phn c s dng rng ri trong cng ngh sn
xut bnh ko. Thnh phn dinh dng ca sa rt phc tp. Sa c thm vo nhm mc ch
lm tng gi tr dinh dng ca sn phm bnh ko, to mi c trng, mang hng v sa. Tuy
nhin, ngoi nhng mc ch chnh trn, sa v cc thnh phn ca sa cn to nn nhng tnh
cht khc cho sn phm bnh ko nh to cu trc, bng
Tng thnh phn trong sa c nhng tc ng hnh thnh nn tnh cht ca sn phm bnh ko.
2.2.7.1. Thnh phn bo trong sa
Cc cht bo trong sa to nn nhng mi v rt c trng cho sn phm bnh ko. y
chnh l tc dng ln nht ca cc thnh phn cht bo sa trong bnh ko. Ngoi ra,
cc thnh phn cht bo trong sa cn l mt cht mang nhm gi li mt s mi hng cho
bnh ko.
Cc cht bo trong sa l cc cht hot ng b mt, cc cht bo ny s gp phn gi
cc thnh phn kh bn trong cu trc ca bnh ko.
Trong cng ngh sn xut cc loi bnh ko mm, cc thnh phn cht bo c tc dng
duy tr m bn trong sn phm, gip sn phm c mm nht nh trong qu trnh bo qun
v ch bin.
-
Mt khc, cc thnh phn cht bo to nn nhng gi tr cm quan cho sn phm bnh
ko. Cc cht bo c ph bn ngoi b mt sn phm lm sn phm sng bng, bt mt ngi
tiu dng. ng dng ny c s dng rng ri trong sn xut bnh ko.
Trong qu trnh ch bin, cc thnh phn bo nh cc cht dn nhit gip cho qu trnh
ch bin d dng hn, hon thin hn.
Ngoi ra, vic s dng cht bo trong bnh ko cn nhm mc ch to cu trc xp cho
bnh ko.
2.2.7.2. Thnh phn protein ca sa
Thnh phn protein trong sa gm hai thnh phn chnh: casein v whey.
Cc protein casein c kh nng ng t, da vo tnh cht ny, ta c th s dng protein
t ngun sa nh mt ph gia to cu trc cho sn phm bnh ko.
Thnh phn casein trong sa c kh nng to nh tng rt cao, whey trong sa cng c
th to h nh nhng khng tt bng casein. Ngoi ra, cc thnh phn ny c tc dng gi bn v
n nh h nh tng trong sn phm bnh ko.
Cc thnh phn protein ny cn c kh nng gi cc thnh phn kh, n nh bt trong
cu trc sn phm bnh ko.
Mt ng dng khc ca cc thnh phn ny l to nht cho dung dch, iu ny c
quan tm nhiu trong qu trnh ch bin v sn xut bnh ko.
Tm li, ng dng ca ngun protein sa trong sn xut bnh ko rt a dng v phong
ph.
2.2.7.3. Thnh phn lactose v cc ng
Trong t nhin, ng lactose ch c tm thy trong sa. Lactose c nhng tnh cht
c bit, nhng c tnh ny c s dng trong cng ngh sn xut bnh ko.
Thng thng, ng lactose dng tinh th ngm mt phn t nc, cu hnh -lactose.
ng phn ny, lactose d dng ha tan trong nc. Khi kt tinh nhanh dung dch ng
lactose bo ha nhit 93,5C s thu c tinh th -lactose.
-
Ngoi ra, nhit cao, cc thnh phn ng b caramel ha to mu sc v mi v c
trng cho sn phm. ng dng ny c p dng trong sn xut ko caramel v toffee. Cc
thnh phn ng cn phn ng Maillard vi cc thnh phn protein trong sa to ra mu nu v
hng v c trng cho mt s sn phm bnh.
2.2.8. Cc cht nh ha (emulsifiers) [7]
Cc nh tng l nhng h phn tn ca hai cht lng khng trn ln nhau m mt trong
hai c mt di dng nhng git nh ca pha b phn tn cn cht lng kia di dng pha lin
tc. Phn ln cc nh tng thc phm u l kiu du trong nc hoc nc trong du. ng
knh ca git cht lng b phn tn l 0,1 - 50 m.
2.2.8.1. Ph gia l cht nh ho
Cht nh ha l nhng hp cht c thm vo trong thc phm nhm to ra s phn tn
gia hai hoc nhiu cht khng c kh nng ha ln vo nhau. Nhng cht lng khng tan vo
nhau l cht bo, nc, v mt s cht khc. Kh nng ha ln vo nhau ty thuc vo loi cht
nh ha, cng nh t s ca du v nc v thnh phn khc nh tinh bt, protein v cc cht
kh khc.
Cht nh ha c tc dng lm gim sc cng b mt gia hai pha, iu ny lm tng kh
nng khuch tn gia cc pha kh phn tn. Cht nh ha hu ht l ester ca acid bo vi cc
polyol nh glycerol, sorbitol, propylene glycol v saccharose. Mt s hp cht cng th hin kh
nng nh ha nh tinh bt, protein
Mt s cht to nh :
+ GMS: glycerol monostearate
+ DATEM: diacethylated tartaric esters of monoglycerides
+ SS: sorbitan stearates
+ SSL: sodium stearoyl lactate
+ SMG: succinylated monoglycerides
-
Lecithin: l mt hp cht t nhin c trong c th tt c cc sinh vt sng nhng tn ti
mt lng ln trong thnh phn ca lng trng (810%) v trong ht u nnh (2,5%). Trong
thng mi, lecithin c chit t u nnh v gi r vi thnh phn:
Du u nnh 35%
Phosphatidyl choline 18%
Cephalin (Phosphatidyl ethanolamine) 15%
Inositol phosphatide 11%
Phosphatide khc v cht bo phn cc 9%
Sterol glucoside 12%
Lecithin thng phm c th dng lng, ko ty mc ch s dng.
2.2.8.2. Ph gia lm bn nh tng
Cht lm lm bn nh tng l cc cht hot ng b mt, trong phn t c nhm ho
nc (hydropheli) v nhm k nc (hydrophobe).
Hin tng tch pha l hin tng khng mong mun trong sn xut thc phm. Do
cn phi s dng ph gia lm bn nh tng hn ch hin tng tch lp.
Ph gia lm bn nh tng khc vi ph gia to ra nh tng. Cc ph gia lm bn nh
tng l cc ph gia c s dng nhm mc ch lm pha phn tn n nh trong pha lin tc.
Ph gia lm bn nh tng c chia lm hai loi :
- L cc ester mt phn ca cc acid bo v cc polyol:
+ Mono v diglycerid.
+ Cc dn xut ca monoglycerid, ester ha bi acid: acetic, lactic, citric...
-
+ Sucroester v sucroglycerid.
+ Ester ca propylene glycol.
+ Ester polyglycerid vi acid bo.
+ Dn xut ca acid lactic.
+ Ester ca sorbitol.
- Phospholipid (Lecithin)
2.2.9. Tinh bt bin tnh
a. Ngun gc:
Nhm tinh bt bin tnh c tc dng lm tng dy, ng c, n nh v
tng khi lng ca sn phm thc phm.
Cc tinh bt bin tnh u c sn xut t cc loi tinh bt thng. Loi tinh bt
c s dng nhiu nht l tinh bt bp v tinh bt khoai m. Ty theo cch bin tnh, chng
c chia thnh cc loi:
Tinh bt bin tnh kiu chuyn i nhm chc
Tinh bt bin tnh kiu lin kt ngang
Tinh bt bin tnh bng phng php vt l
Tinh bt bin tnh kiu thay i gen.
Trong cc loi trn, quan trng nht l loi tinh bt bin tnh kiu lin kt ngang.
Tnh cht:
Tinh bt bin tnh kiu chuyn i nhm chc: c to thnh do vic ct cc phn t
ca lin kt glucoit, thay th nhm OH bng cch oxi ha thnh nhm andehyt, ceton, cacboxyl
v c s ti sp xp phn t. Mc ch ca qu trnh ny l lm gim nht ca tinh bt, ngoi
ra cn lm bin i mt s tnh cht khc nh kh nng ho tan trong nc lnh, xu hng to
thnh dng gel hay dng paste.
-
Tinh bt bin tnh kiu lin kt ngang: c to thnh do vic x l tinh bt vi cc
tc nhn lm bn tinh bt, c kh nng phn ng vi nhm OH ca phn t tinh bt iu kin
tinh bt cha b trng n. Khi , mt phn t tc nhn lin kt ngang s phn ng vi gc
OH ca 2 phn t tinh bt khc nhau, hnh thnh mt cu ni nhm cng c cc lin kt hydro c
nhim v gi cho ht tinh bt nguyn vn. Mc ch l lm cho ht tinh bt khng nhanh chng
b ph v khi gia nhit, ko di khong thi gian ht tinh bt c hydrat ha cc i cng
nh lm tng nht cc i cho dung dch.
Tinh bt bin tnh kiu thay i gen: c to thnh bng cch tc ng ln h gen
ca c6y trng sn sinh ra loi tinh bt , nhm mc ch to cho ht tinh bt thu c c hm
lng amylo hoc amylopectin cao hn nhiu so vi tinh bt bnh thng.
Tinh bt bin tnh bng phng php vt l: c th dng bin php ti sy kh tinh
bt tng kh nng gi m ca ht tinh bt; kt hp vi cc ph gia khc lm tng tnh chy
ca ht tinh bt kh; trn vi tricanxi photphat v cc cht v c khc n bao ph b mt ht,
nhm lm tng tnh linh ng ca ht tinh bt; x l nhit trc trnh tinh bt b trng n
trong nc lnh (tinh bt h ha trc)
Li ch:
Nh cc tnh cht nu, tinh bt bin tnh c s dng rt rng ri trong ngnh
sn xut bnh, nh cc loi bnh m, bnh bng lan, cc loi kem trang tr, nhn bnh Ngoi ra
mt phn nh c dng trong bnh snack, ko mm, ko chocolate
Liu lng s dng:
Do tinh bt bin tnh c ngun gc t tinh bt t nhin, cc qu trnh sn xut c
x l ph hp nn chng c cng nhn l s dng an ton khng gii hn cho thc phm.
Xu hng s dng:
i vi cc sn phm bnh cng nghip sn xut nc ta, vic s dng tinh bt bin tnh cn
kh t. Tuy nhin, ngi tiu dng dn lm quen vi cc sn phm cng ngh nc ngoi, a
s c s dng cc loi tinh bt bin tnh do n em li mt s tnh cht cm quan u vit m tinh
bt thng khng c c. Do , vic s dng tinh bt bin tnh trong sn xut bnh l cn
-
thit, nhm nng cao cht lng cng nh ko di hn s dng ca sn phm, ph hp vi xu
hng tiu dng hin nay.
* Gii hn ti a mt s ph gia lm tng gi tr cm quan thc phm dng sn xut
bnh [8]
STT Tn ting Vit Tn ting Anh Chc nng INS ADI ML
1 Acesulfam kali Acesulfam
potassium
Cht ngt tng
hp
950 0-15 GMP
2 Acid tartaric Tartaric Acid iu chnh
acid
334 0-30 10000
3 Canthaxanthin Canthaxanthine Phm mu 161 0-0,03 GMP
4 Caroten Carotenes Phm mu 160 CX GMP
5 Caramen nhm
III (x l amoni)
Caramen III-
Ammonia process
Phm mu 150 0-200 GMP
6 Allura AC Allura Red AC Phm mu 129 0-7 300
7 Amaranth Amaranth Phm mu 123 0-0,5 300
8 Erythrosine Phm mu
9 Este ca
polyglyxerol vi
axid bo
Polyglyxerol
Esters of Fatty
acid
Nh ha 475 0-25 10000
10 Este ca sucroza
vi acit bo
Sucrose Esters of
Fatty acid
Nh ha 473 0-16 GMP
11 Etyl Maltol Ethyl Maltol iu v, n nh 637 0-2 200
12 Etyl vanillin Ethyl vanillin To hng CQ 0-50 Lng
-
nh
13 Maltol Maltol iu v, n nh 636 0-1 200
14 Propylen glycol
alginat
Propylen glycol
Alginate
Nh ha 405 0-70 5000
15 Vng riboflavin Riboflavin Phm mu 101i 0-0,5 GMP
16 Natri nhm
phosphat-axit
Sodium
Aluminium
phosphate acid
iu chnh
acid
541i 0-0,6 2000
17 St oxit, Iron oxide, Red Phm mu 172ii 0-0,5 GMP
18 St oxit, en Iron oxide, White Phm mu 172i 0-0,5 GMP
19 St oxit, vng Iron oxide,
Yellow
Phm mu 172iii 0-0,5 GMP
20 Sorbitan
Monolaurat
Sorbitan
Monolaurate
Nh ha, n
nh
493 0-20 5000
21 Sorbitan
Monooleat
Sorbitan
Monooleate
Nh ha, n
nh
494 0-20 5000
22 Sorbitan
Monopalmitat
Sorbitan
Monopalmitate
Nh ha, n
nh
495 0-20 5000
23 Sorbitan
Monostearat
Sorbitan
Monostearate
Nh ha, n
nh
491 0-20 5000
24 Sorbitan
Tristearat
Sorbitan
Tristearate
Nh ha, n
nh
492 0-20 5000
25 Stearyl tartrat Stearyl Tartrate Cht nh ha 483 0-500 4000
-
26 Sucroglyxerit Sucroglyxerides Cht nh ha 474 0-30 10000
27 Sucraloza Sucralose Cht ngt tng
hp
955 0-15 150
28 Vng Tartrazin Tartrazine Phm mu 102 0-0,75 300
29 Vng Sunset FCF Sunset Yellow
FCF
Phm mu 110 0-2,5 300
30 Xanh Brilliant
FCF
Brilliant FCF Phm mu 133 0-12,5 200
31 Xanh lc bn
FCF
Fast green FCF Phm mu 143 0-25 100
32 Lexitin Lecithins Nh ha 151 322 CX
Ghi ch:
- INS: h thng nh s quc t (International Numbering Sytem) l k hiu c y ban Codex
v thc phm xc nh cho mi cht ph gia khi xp chng vo danh mc cc cht ph gia thc
phm.
- ADI: lng n vo hng ngy chp nhn c (Acceptable Daily Intake) l lng xc nh ca
mi cht ph gia thc phm c c th n vo hng ngy thng qua thc phm hoc nc ung
m khng gy nh hng c hi ti sc khe. ADI c tnh theo mg/kg trng lng c
th/ngy.
ADI c th biu din di dng: - Gi tr xc nh
- Cha quy nh (CQ)
- Cha xc nh (CX)
-
- ML: gii hn ti a trong thc phm (Maximum level) l mc gii hn ti a ca mi cht ph
gia s dng trong qu trnh sn xut, ch bin, x l, bo qun, bo qun v vn chuyn sn
phm.
- GMP: thc hnh sn xut tt (Good Manufacturing Practices) l vic p ng cc yu cu s
dng ph gia trong qu trnh sn xut, x l, ch bin, bo qun, bao gi, vn chuyn thc phm,
bao gm:
+ Hn ch ti mc thp nht lng ph gia thc phm cn thit phi s dng;
+ Lng cht ph gia c s dng trong qu trnh sn xut, ch bin, bo qun, ng
gi v vn chuyn khng nh hng ti tnh cht l ha hay gi tr khc ca thc phm;
+ Lng ph gia thc phm s dng phi ph hp vi cng b ca nh sn xut c
chng nhn ca c quan c thm quyn.
2.3 . Ph gia thc phm tng gi tr dinh dng
Vo u th k trc, con ngi mc phi rt nhiu loi bnh him ngho ch v thiu cht dinh
dng nh bnh bu tuyn gip v thiu iod cn thit cho s to ra hormon ca tuyn ny; bnh ci xng
tr em v thiu vitamin D, khng hp th c calci nn xng mm v bin dng; bnh scurvy gy sng,
chy mu nu rng, lu lnh vt thng v c th dn n t vong nu ko di, ch l do thiu sinh t C khi
khng dng rau tri ti.
Ngy nay, nh cc cht dinh dng cn thit ny c b sung vo thc phm trong qu trnh ch
bin m cc bnh va k him khi xy ra, ta gi l cc cht ph gia dinh dng (nutritional additives).
Thc phm b sung dinh dng tr thnh mt khi nim rng hn, v c th c sn xut bi nhiu l do.
u tin l khi phc li cc cht dinh dng b mt trong qu trnh ch bin thc phm, c gi l lm
giu cht dinh dng (enrichment). Trong trng hp ny, lng cht dinh dng c thm vo l xp x
lng t nhin trong thc phm trc khi ch bin. L do th hai l thm vo nhng cht dinh dng m c
th khng c mt trong thc phm t nhin, c gi l tng cng cht dinh dng (fortification).Trong
trng hp ny, hm lng cht dinh dng b sung c th cao hn so vi hm lng trc khi ch bin.
V vy, da vo cc l do trn, muc ch cui cng ca vic b sung ph gia dinh dng l: duy tr
cht lng dinh dng ca thc phm, gi mc dinh dng y ci thin hoc ngn nga s thiu
ht dinh dng trong mt cng ng hoc trong cc nhm ngi c nguy c b thiu ht mt s loi cht
-
dinh dng nht nh (v d, ph n ngi cao tui, ngi n chay, mang thai, vv); ng thi tng gi tr
gia tng dinh dng ca mt sn phm thng mi; v b tr cho nhng chc nng cng ngh nht nh
trong ch bin thc phm.Tuy nhin, vic b sung cht dinh dng trong thc phm cng c tiu chun
ha bng nhng quy nh v hm lng v thnh phn cht dinh dng c th, v nhng cht c dng
thm vo thc phm trong khi ch bin c gi chung l ph gia dinh dng (nutritional additives)
Phn loi ph gia thc phm tng gi tr dinh dng:
Cc nhm ph gia thc phm tng gi tr dinh dng:
- Cc vitamin: bao gm
+ Cc vitamin tan trong du: A, D, E, K
+ Cc vitamin tan trong nc: cc vitamin cn li, bao gm B, C, H
- Cc cht khong: bao gm
+ Cc nguyn t a lng
+ Cc nguyn t vi lng
- Cc acid amin:
+ Cc acid amin khng thay th
+ Cc acid amin thay th
Mt vi sn phm bnh b sung ph gia thc phm tng gi tr dinh dng:
Bnh Resoni: c b sung cc lai Vitamin A , C , B6 , B12 v Acid
Folic .
Theo kt qu phn tch ca VIN DINH DNG VIT NAM, bnh
RESONI c ch s ng huyt l 34,9% (< 40 %), s dng tt cho
ngi i tho ng. [12]
-
Bnh cracker AFC: Nguyn liu b sung Canxi, Vitamin D, Vitamin E, Cht x, DHA...
Bnh KRACKII b sung Lysine, vitamin v khong cht h tr
tng cng v phng chng thiu vi cht.
Bnh quy Tiger l bnh quy u tin ti Vit Nam c s kt hp c
o ca hng v v dinh dng hp l cung cp sc mnh cho
tr chin thng mi ngy. Cng thc ENERMAXX c trong bnh
cha 9 vitamin cn thit (A, B1, B2, B3, B6, B9, B12, D, E) v 6
khong cht thit yu (canxi, magie, st, selen, I t, km).
CHNG 3 QUY TRNH CNG NGH SN XUT BNH TNG QUT V PH GIA
S DNG CHO MT VI LOI BNH
3.1 Quy trnh cng ngh sn xut bnh tng qut
nh kem
Nho bt
bt nho
To hnh
Nng
Ph gia Nguyn liu ph
Bt m
-
3.2 u nhc im ca bnh
u im
Hu nh cc loi bnh hin nay u c cht lng tng i cao, khu v ph hp vi
ngi tiu dng, ang rt c a chung. cc sn phm ny phong ph v hnh dng, kch
thc, chng loi, mi v, a dng v cht lng (v d bnh mn, bnh b sung canxi, bnh b
sung vitamin, bn b sung DHA)v ngy nay th trng bnh khng ngng ci tin v cht
lng hn na tha mn thm nhu cu ngy cng ln ca ngi tiu dng. i vi tm l ca
ngi tiu dng hin nay khng nhng bnh phi ngon, b dng, r tin m c v hnh thc bn
ngoi ln vic ph hp vi s thch ca bn thn cng l iu ng ch v d nh cc loi bnh
cng thin v t nhin cng tt nh nguyn liu t thin nhin t cht bo qun, hm lng cht
bo thp, t nng lng; cc loi bnh c th dng c cho ngi n king hay nhng loi bnh
chay m rng i tng s dng bnh
Nhn chung cc loi bnh hin nay t cc yu cu v v sinh an ton thc phm, mu m a
dng, hn s dng tng i di thng khong mt nm. Cc yu t v cu trc nh mm,
gin, dai, v mu sc, mi v tng i cao, v ngy cng c nghin cu v pht trin
hn na.
Nhc im
Bn cnh nhng u im trn th dng bnh hin nay cn c mt vi khuyt im nh:
gi sn phm cn cao lm gim kh nng tiu th sn phm, c hin tng hng bnh trong khi
hn s dng vn cn. Cc qu trnh hng ny ch yu l v gi tr cm quan nh bnh b tr mi,
-
bnh c mi du, hoc nhng mi khng mong mun, bnh b mc nhng nguyn nhn gy ra
hin tng ny c th do qu trnh vn chuyn v bo qun sn phm, c th do s dng cc cht
bo qun khng ph hp
Nhc im ni bt hin nay l hin tng bnh b oxy ha to mi kh chu trong thi
hn s dng, nht l cc sn phm bnh c hm lng bo cao. Do cn nghin cu b sung
cc cht chng oxy ha nng cao kh nng chng oxy ha nhm ko di thi gian s dng ci
thin nhc im ny m khng lm nh hng n sc khe ca ngi tiu dng.
Cc sn phm hin nay a dng v mi v v mu sc, cu trc. Tuy nhin, ch yu l
cc ph gia a vo to hng v v mu sc cng nh cu trc v cc mi hay mu t t
nhin thng khng bn khi nng nhit cao th nhng tnh cht ny khng cn li nhiu
na do ngi ta thng phun hng vo sn phm bnh sau khi nng v b sung thm mu
nhn to trong qu trnh phi trn cc nguyn liu.
Do chng ti s trnh by qu trnh s dng cc loi ph gia s dng trong mt vi
loi bnh hin c trn th trng Vit Nam.
3.3 Tnh hnh s dng ph gia ca mt s loi bnh
3.3.1 Nhm bnh kh
L loi bnh c m rt thp. m ca bnh ny ch giao ng trong khong t 2-5%.
Chnh v m thp nh vy nn thi gian bo qun, s dng cc loi bnh ny rt lu nu c
bao gi trnh ht m.
Trong mi nhm bnh ngi ta cn chia lm nhiu loi bnh khc nhau.
Bnh bch quy (biscuit hoc cookies) l loi bnh c nng hai ln, giu ng,
shortening, m thp (2 - 5%). Bnh bch quy cng rt a dng v phong ph v khu v, cht
lng, mu m. V trong qu trnh sn xut cc sn phm bnh kh hin nay c b sung
nhiu loi ph gia nhm gip duy tr v ci thin cht lng bnh, nhm mang li hiu qu cao
nht. in hnh l bnh cookie v bnh cracker.
Quy trnh cng ngh sn xut bnh cracker v cookies
S quy trnh cng ngh sn xut bnh cracker
-
ng Sa Men Ph gia (bt
ni, mu, hung liu)
Bt m
Chun b
Trn bt
bt
Cn, nh hnh
Nng
Phun du
Lm ngui
Shortening
Dch mi
Nguyn liu ph
-
S quy trnh cng ngh sn xut bnh cookies
Nguyn liu
ph Bt m
Chun b Chun b
Nc ung xay Shortening Sa bt Trng Ph gia
-
Nhm cht oxi ha mi ci thin v nng cao kh nng chng oxi ha, nhm ko di
hn na thi hn s dng. cc nhm cht ph gia s dng ph bin trong sn xut bnh cracker
v bnh cookies nh:
Lecithine: dng lng, qunh, mu v0ng nu, khng tan trong nc, l cht nh
ha v cht hot ng b mt c hiu qu cao. ng thi l cht chng oxi ha, tr hon qu trnh
i ha sn phm, l cht n nh, cht to ni.
-
Gii hn s dng trong bnh nng: 0.5 2% cht bo.
ADI: cha xc nh.
Mono glycerides: dng lng hoc rn, mu vng n vng ng, mi v d chu.
Mono glycerides l cht nh ha, cht hot ng b mt gip phn tn tt cc thnh phn cht
bo trong bt nho , lm gim sc cng b mt, tng lc nho, tnh to bt n nh, tn kh nng
gi kh trong qu trnh ch bin, hiu qu gip bnh xp gin.
ML: bnh Cookies v Cracker : 0.5 1% trng lng bt.
ADI: cha xc nh
Nhm cc cht to mu
Mt s cht to mu thng s dng trong bnh nng
Riboflevin (mu vng)
ADI :0 0.5 mg/kg.
Amaranth, erythrosine (mu ta)
ADI: 0 0.5 mg/kg
Sunset yellow FCF (mu vng cam)
ML bnh nng: 300 mg/kg.
ADI: 0 2.5 mg/kg.
Tartrazine (mu vng chanh)
ADI: 0 7.5 mg/kg.
Brillant blue (mu xanh dng)
ADI: 0 12.5 mg/kg.
Nhm cht to mi: hng liu thm vo bnh gip sn phm thm phong ph v hp
dn. Hng liu t nhin: l cc loi tinh du c trch ly t thc vt nh: hng cam, chanh ,
da, c ph, da Hng tng hp l cc este tng hp, cng c mi nh nhm hng t nhin.
Nhm cht chng oxi ha
-
Acid ascorbic (vitamin C):l tinh th mu trng, tan trong nc, khng tan trong
dung mi bo
ADI: cha xc nh
Butylat hydroxy anisol (BHA): cht lng c, mu trng, tan trong nc. L cht
chng oxi ha v bo qun hiu qu cao, c s dng trong cc sn phm giu bo.
ADI: 0 0.5 mg/kg.
Butylat hydroxy toluen (BHT): l cht rn mu trng, khng tan trong nc. L
cht bo qun thc phm, cht n nh, nh ha cho shortening, ngn nga s hng, i kht ca
cht bo.
LD 50: 890 mg/kg
ADI: 0 0.3 mg/kg.
Acid citric: tinh th dng bt, khng mu, khng mi, tan tt trong nc, ru,
ete. L cht chng oxi ha kh yu nn thng c s dng chung vi BHT, BHA.
ML bnh nng: 1200mg/kg.
ADI: cha xc nh.
Nhm cht bo qun( khng vi sinh vt)
Acid sorbic, Kali sorbat, Natri sorbat, Canxi sorbat: Acid sorbic chng hiu qu
cc loi vi khun hiu kh., t tc dng vi Clostridium v khng nh hng n nm men.
ML bnh nng: 2000 mg/kg.
LD 50: 8700 mg/kg.
ADI: 0 25 mg/kg.
Acid propionic, Natri propionat, Canxi propionat: l cht chng hiu qu cc loi
nm mc, khun Bacillus, c bit l trong cc sn phm bnh nng.
ML bnh nng: 2000 mg/kg,
acid s dng nng : 0.1 0.3%
-
LD 50 (acid): 2600 mg/kg.
ADI: cha xc nh.
Acid benzoic, Natri benzoat:l cht bo qun c tc dng c hiu vi nm men,
nm mc v t c tc dng i vi vi khun.
ML bnh nng (acid): 40 ppm.
ML bnh nng (dng mui): dung dch 0.1%.
LD 50 (acid): 1700 3700 mg/kg.
ADI: 0 5 mg/kg.
3.3.2 Nhm bnh ti
L loi bnh c s dng ngay khi sn xut, loi bnh ny rt d b vi sinh vt tn cng
v lm hng trong thi gian rt ngn. Nu c bo qun lnh th c th ko di thi gian bo
qun nhng ch c khong mt thng tr li. in hnh l hai loi bnh: bnh c m ln
(cc loi bnh bng lan), bnh giu lipid (bnh ba).
3.3.2.1 Bnh ba
Quy trnh cng ngh
Tnh nng sn phm
Bnh c hm lng m kh cao, khong
pH ca bnh nm trong vng trung tnh, li cha
nhiu cht dinh dng nn l mi trng rt
thch hp cho vi sinh vt pht trin c bit l
nm mc, vi khun staphylococcus Aureus .
Ngoi ra bnh cn c hm lng lipid cao. Lipid trong sn phm phn ln c ngun gc
t ng vt ch yu l m heo thu c bng cch nu nng chy m l nhit 80oC ( m
khng c mu v khng c mi), m ni ln b mt v c tch ra bng ly tm. Thnh phn ca
m l tryglyxerid hn tp nh stearodiolein (15%), -palmitodistearin (2%). Dipalmistearin
(3%). Dipalmitoolein (2%), c cha nhiu cc acid bo no ln khng no, phn t lng ln. hn
-
na c thm mt lng du thc vt. do rt d b oxy ha ch yu do tc nhn nhit , nh
sang.
Ph gia s dng v vai tr ca chng
Bnh c sn xut ch yu da trn phng php truyn thng nn c th kim sot
hon ton cc iu kin vi sinh vt c tnh ca bnh rt d b nhim cc vi sinh vt khc nhau
trong qu trnh ch bin v bo qun.
Cc ph gia thng s dng trong bnh ch yu l cc sorbic (c kh nng tan tt trong
du nhng kh nng tiu dit vi sinh vt km do mi trng khng acid), cc mui K, Na, Ca
sorbet (thng dng K sorbet) chng vi khun, nht l nm mc thng hay pht trin trn b
mt bnh, lm mt gi tr cm quan ln hng bnh. Ngoi ra tng thi gian bo qun bnh ta
phi kt hp vi cc yu t mi trng, gi bnh trong iu kin nhit thp, thng thong
trnh nh sng trc tip. Bnh ba hin nay ch c bo qun trong thi gian ti a l mt thng.
Cc cht to hng s dng: theo truyn thng ta thng dng hng su ring cho loi
bnh ba truyn thng. C th s dng cc loi hng khc cho cc loi bnh ba c nhn khc
nhau nh hng khoai mnngoi ra tng hng v cn cho thm hng vani.
3.3.2.2 Bnh bng lan
Tnh nng ca sn phm
Bnh bng lan l loi bnh c hm m v
hm lng lipid kh cao, bnh cn c n hi,
cu trc mm, th tch ln, c th c nhng hng
thm ty vo nh sn xut. Bnh cn phi ch vi
nhng nguyn liu ph khc to ra nhiu loi
bnh khc nhau nh: bng lan kem, bnh mt tri cy, bnh bng lan cun, bng lan chocolate
Do c hm m, lng ng v cht bo cao nn bnh l mi trng rt d nhim vi sinh
vt, c bit l nm mc v cc loi vi khun thng nhim vo thc phm ch bin sn nh vi
khun lactic, staphylococcus aureus, E. coli
Ph gia s dng
-
Ph gia s dng trong qu trnh sn xut phi k n trc tin l cc cht to nh. Ch
yu dng:
Lecithin (s gy mi kh chu nu liu lng cao hn 0,5%)
Mono v digyceride ca cc acid bo, cc ester propylene glycol ca acid bo ( cht E471
hay E477).
Cc ester acid diacetytaric v cc acid bo ca ester glycerol: dng lng mu vng n
vng hi anh, c mi b b i, tan trong glyxerin, nc. l cht l nh ha trong mi bnh nng,
cc sn phm sa, b, magarin, du, kem trn bnh, c Ml bnh nng: 10000 hay sodium
lactylates (E472, E481).
Cc cht lm dy nh: hydroxyl propyl diamidon photphate (E1442) c ADI khng gii
hn.
Cc cht to hng nh tinh du chanh, vani, cam
Cc cht mu nh annatto l phm mu t nhin c ADI: 0- 0,065.
Cc cht chng vi sinh vt nh: cc mui ca acid sorbat thng dng mui K sorbat)
Vai tr
Cc cht to nh, to h phn tn ng nht, n nh cu trc ca khi bt nho, m bo
cu trc ca bnh trong lc nng v sau khi thnh phm.
Cc cht lm dy s tng th tch ca khi bt, lm bnh n to v cu trc bnh xp hn.
Cc cht gy mi, to mu c cho vo ty loi bnh, ty s thch ca ngi tiu dng
m nh sn xut la chn cho thch hp. chng gp phn lm tng gi tr cm quan ca bnh.
3.3.3 Mt s nghin cu v ph gia ca bnh [7]
Cc FMBRA [6] cho thy rng vic gim 15-20% cht bo c th t c thnh cng
trong cng thc bnh cng v ngt v s dng mt ester DATA mc 0,75% ca trng lng
cht bo . Ester c b sung thm cht bo. Trong trng hp cc cng thc bnh quy Lincoln,
-
gim cht bo bt li nh hng n tnh nht qun ca bt m i hi mt s thay i nc cho
cng thc.
SSL v SSF (natri stearoyl fumarate) mc 0.5% theo trng lng bt c mt nh
hng ng k vo vic tng cng s n ca cookies trong nng. SSL v ETO-en trng
(ethoxylated monoglycerides) dng nh l c bit hiu qu trong vic lm mm kt cu cookie
khi c s dng mc khong 0,4% da trn trng lng bt m.
Hiu ng lm mm trn kt cu bnh quy nhn c s ch nht trong cc ng dng
bnh quy v n cho php mt mc gim cht bo (v tit kim chi ph) t c mt cht
lng mong mun khi n. Burt v Thacker [1] tp trung vo kha cnh ny, nhng h cng kim
tra cc thay i hng v bng cch nm th nghim. H thy rng este, SSL v este acid citric
ca monoglycerides l hiu qu nht lm mm cu trc v cc ch b sung c DATA
este v SSL c gi trc tip vo bt v este ca axit citric thng qua cc bt m.
SSL, SSF v SMG (succinylated monoglycerides) ci thin cht lng ca bnh cookies
c lm t bt nh l mt thay th cho bt mm v iu ny c th quan trng chng li cc
bin i trong bt xy ra t nm ny sang nm khc. Cc tinh bt v protein tnh nng to phc
ca mt s hp cht quan trng i vi kh nng cung cp. Nng cao kh nng ph kn ca bt
nho t cht bo v cc sn phm lm t hn hp ca la m v bt ng cc khc nh la min v
k - c gi l bt hn hp. Ct GMS, DATA este, este ca chng polyglycerol c v y ha
hn nht i vi cc chc nng ny.
Mt s thng hiu bnh quy vi mc gim ng k cc cht bo c thc hin
thnh cng. Vic thay th m bnh thng bi rt n nh nh tng cht bo cng vi DATEM
c mt s kt qu tt nht, nhng cc nh tng t s kh khn x l. Lecithin c s
dng trn nhiu loi bnh bch quy. N thng c ha tan trong cht bo trc khi thm vo
cng thc. N h tr s pht tn ca cht bo trong bt nho v ci thin cc nh tng trong
kem.
Cht nh cng c th tm thy s dng cho rong cng ngh biscuit:
- S dng cht lng thay v cht bo trong bt biscuit (nh GMS)
- Kim sot cht bo bt do v kem, trong trong bo qun hay khi c s dng trc
tip t mt my lm lnh hoc cht nh ha, bng cch thay i loi tinh th
(Sorbitan tristearate v monoglycerides khng bo ha)
-
- Ci thin kh nng chu mc khc nhau v cht lng ca protein trong bt bnh quy,
i vi my ct bt bt nho v nng nhit nng trong bnh v cc loi bn ngt
( nh cht SSL v DATA este).
- Ci thin c cc mc khc nhau v cht lng ca protein trong biscuit dng nh
tng cht n nh hoc huyn ph yu cu nh cht tng hp cho cc h thng t
ng pha trn (loi s ph thuc vo bn cht ca cc thnh phn trn ln).
Trong thc phm cht nh ho c th hnh ng theo mt s cch khc nhau.
Chng bao gm:
- n nh dng nh tng du trong nc
- n nh dng nh tng nc trong du
- Thay i kt tinh cht bo
- Thay i ph hp bt nho, tinh bt keo dnh v cc kha cnh ca phc hp vi
protein, tinh bt v ng.
- Du bi trn bt nho c hm lng bo thp [7]
KT LUN
Ph gia thc phm l mt lnh vc quan trng trong cng nghip ch bin thc phm, c
xu hng ngy cng m rng, nht l trong cng ngh sn xut bnh. Ngy nay, hu ht cc sn
phm bnh ko, cng nh thc phm ni chung, u c sn xut quy m cng nghip v
c vn chuyn, phn phi trong nhng khong cch rt xa. Do , phi bo m cho hn s
-
dng ca sn phm l iu ht sc cn thit. Bn cnh , yu cu v cht lng sn phm ca
ngi tiu dng ngy cng cao, yu cu v s ngon ming, b dng, thc phm cn phi m
bo v hnh thc, cm quan, c bit l phi m bo v sinh an tan thc phm.
Sn xut bnh l mt trong nhng ngnh thc phm c t lu i v ph bin nht.
Nhng cng l i tng c ci tin v pht trin lin tc, bao gm quy trnh cng ngh, thit
b sn xut, s dng cc vt liu mi, c bit l cc ph gia thc phm. Li ch ca ph gia thc
phm l rt ln, nhng n cng c nhng gii hn v nguy hi nu s dng khng ph hp. Do
, vic hiu bit nhng loi ph gia ph hp cho cc loi sn phm bnh l mt iu ht sc cn
thit.
MC LC
CHNG 1 C S CHUNG ............................................................................................... 3
1.1.Tm hiu chung v bnh ............................................................................................... 3
1.1.1.khi nim v bnh ................................................................................................. 3
1.1.2.Phn loi bnh ....................................................................................................... 3
-
1.1.3.Nguyn liu chnh cho sn xut bnh ..................................................................... 5
1.2.Tm hiu chung v ph gia thc phm.......................................................................... 8
1.2.1.Khi nim ph gia thc phm: ............................................................................... 8
1.2.2.Phn loi ph gia thc phm : ................................................................................ 8
CHNG 2 CC LOI PH GIA TRONG SN XUT BNH ...................................... 10
2.1 Ph gia bo qun........................................................................................................ 10
2.1.1 Butylat hydroxy anisol (BHA) ............................................................................. 10
2.1.2 Butyl hydroxy toluen (BHT) ................................................................................ 11
2.1.3 Propyl gallat (PG)................................................................................................ 11
2.1.4 Tert butyl hydro quinon (TBHQ) ...................................................................... 12
2.2 Ph gia lm tng gi tr cm quan .............................................................................. 12
2.2.1. Cc cht iu chnh acid (acidity regulators) [9] ............................................ 12
2.2.2. Cc cht iu v (flavour enhancers) ................................................................... 14
2.2.3. Cc cht to gel (gelling agents) ......................................................................... 17
2.2.4. Cc cht to bt (whipping agents) ..................................................................... 17
2.2.5. Cht to ngt nhn to (artificial sweeteners)...................................................... 19
2.2.6. Hng liu v phm mu (flavours and colours) ................................................. 21
2.2.7. Sa c s dng nh mt ph gia trong cng ngh sn xut bnh ko .............. 26
2.2.8. Cc cht nh ha (emulsifiers)............................................................................ 28
2.2.9. Tinh bt bin tnh ............................................................................................... 30
Ph gia thc phm tng gi tr dinh dng ....................................................................... 35
-
CHNG 3 QUY TRNH CNG NGH SN XUT BNH TNG QUT V PH GIA S
DNG CHO MT VI LOI BNH ................................................................................ 37
3.1 Quy trnh cng ngh sn xut bnh tng qut ............................................................. 37
3.2 u nhc im ca bnh .......................................................................................... 38
3.3 Tnh hnh s dng ph gia ca mt s loi bnh ......................................................... 39
3.3.1 Nhm bnh kh .................................................................................................. 39
Quy trnh cng ngh sn xut bnh cracker v cookies .................................................... 39
3.3.2 Nhm bnh ti .................................................................................................. 45
3.3.3 Mt s nghin cu v ph gia ca bnh .............................................................. 47
-
TI LIU THAM KHO
[1] BURT, D. J. and THACKER, D. (1981) Use of emulsifiers in short dough biscuits,
Food Trade Review, p. 344.
[2]Danh mc ph gia
[3]Ducan Manley, Biscuit, cookie and cracker manufacturing manuals, Woodhead, 1998,
vol1,4
[4]Duncan Manley, technology of biscuits,crackers and cookies, Woodhead, 2000, 97
[5] Vn Chng, Ph gia v bao b thc phm, Lao ng, 2010
[6] FMBRA (1974) The Use of Emulsifiers in Biscuits, report on a non-confidential
sponsored project on behalf of Food Industries Ltd, FMBRA. (The FMBRA is now incorporated
into the Campden & Chorleywood FRA.).
[7]Technology of biscuits, crackers and cookies
[8]Quyt nh ca b trng b y t s 3742/2001/Q-BYT ngy 31 thng 8 nm 2001
[9]17 Additives ;Technology of Biscuits, Crackers and Cookies
[10] http://community.h2vn.com/index.php?topic=793.0
[11]http://atpvietnam.com/Library/Doc/94/2010/09/Bao_cao_Nganh_Banh_Keo_-_NCKT-
_CTCK_Tri_Viet.pdf.
[12]http://www.snfood.vn/snfood/]