T C . D D & T P 9 ( 1 ) - 2 0 I 3 6. UBND tinh Thira Thien Hue (2012). Thira Thien Hui. Du dja chi Tliira Thien Hue.
Am thirc: Cam chay. Clng thong tin di?n lir (http://www3.thuathienhue.gov.vn/) Summary
STUDY ON CONCEPTION AND HABIT OF HAVING VEGETAIUAN FOODS IN VIETNAM
Wilh a long-standing vegetarian practice of Buddhism tradition and increasing attention to- wards health and environment, there are more and more Vietnamese people converting to vegans and this becomes a popular consumption irend in Vietnam. For a better understanding of the veg- etarian's conception and consumption habits and behavior of consumers, a survey has been carried out on 334 people randomly selected in Ho Chi Minh Ciiy. The results showed that the proportion of vegetarians (50.3%) and of the people who are interested in vegetarian (68%) is relatively high.
This demonstrates the growing demand for vegetarian. The motivation as well as the barriers of practicing vegetarian has been explored The consumption of vegetarian dishes has also been dis- cussed. Positive tliinking about vegetarian dishes has been reported, for example: 74%j of people agreed that a vegetarian diet ensures nutrition intake, 58%i of people agreed that vegetarian restau- rants have good practice for food hygiene and safety. Three criteria for selecting a vegetarian restaurant have been pointed out: good tasting dishes, clean and reasonable price.
Keywords: vegetarian food, representation, consumption habits, vegetarian restaurants.
NGHIEN CtTU BO SUNG VI KHUAN LACTIC VA NAM MEN SINH Rl/dU TRONG QUY, TRINH SAN XUAT
N u ' d c TlTdNG TAO SAN PHAM CO HlTdNG VI CAM QUAN TOT
Nguyen Thi Viet Anh'; Ddng Thi Hdng Anh'; Le Vdn Bdc"
Nudc tuong (soy sauce), la dang gia vi quan trpng pho bien tren the gidi dac biet tai cac nuac chau A. Nghien ciiu nham muc tieu xay dung quy trinh san xual nudc tucmg len men, co chSt lupng san pham dat tot ca ve dinh dudng, an loan ve sinh thyc pham, cung nhir chat lupng cam quan. Nghien ciiu lya chpn 2 chimg nam men va vi khuan co kha nSng chiu n6ng dp mu6i cao (13-16)%!, do la cac chimg nSm men Zygossacharomyces sp. Z2.8 co kha nang len men c6n va chiing Lactobacillus sp.LM 5 co kha nang Ien men lactic phii hop vdi qua trinh len men nuoc tuang. Chiing Lactobacillus sp.LM 5 dugc bo sung sau 5 ngay len men vdi ty 1? 105cfu/ml. Zy- gossacharomyces sp. Z2.8 dugc bo sung sau 10 ngay len men vdi ty le I04cfii/ml. Kit qua san pham thu dupc: san phSm nudc lucmg len men theo quy trinh cai tien quy mo lOOl/me co ch^t Iuong lot han so vdi san pham len men khong bo sung vi khuin va nim men (protein: 17g/l, amino acid: 14,5g/I, axit long: 2,65g/i, dirdng t6ng: 70,5 g/1, etanol: 1,2%). mau sic san phim dam, mdi tham han va dam bao ATTP.
Tir khoa: Lactobacillus planlarum. Zygossacharomyces sp. nirac tucmg len men, v^ sinh an todn thuc phdm, hirang nirdc tirang.
'Vien Cong nghiep thuc phim Ha Npi Phan bien 1: PGS.TS. Nguyin Xuan Ninh - DT: 043.8586786 Trung tam Doping va Y hpc the thao EmaiI:[email protected] Phan bien 2: PGS.TS. Vu Thi Dao -
Vi^n Cong nghiep thirc phim Ha Npi Ngay nhan bai: 11/2012 Ngay dang bai: 15/04/2013
TC.DD&TP 9(1)-2013 I.DAT VAN DE
Nudc tuong la dang gia vi pho thong CO mat lai hau het tren ihi trucmg cac nudc, trong do co Viet Nam.Nguyen lieu chinh de san xuat nudc tuong la dau tirong, mpt dang nguyen lieu thyc vat giau dam, rat lot cho siic khoe ngudi tieu dung.
Trong thdi gian gan day tai Viet Nam, nudc luang san xual bang phuang phap thuy phan bdi HCI dugc phat hien co chiia hgp chat 3-monoclopropan-l,2-diol (3-MCPD) cao gap nhieu lan gidi han cho phep. Day la chat gay ung thu khi sir dung d nong dp cao, trong thdi gian dai.
Dieu nay cho thay can thiet phai co sy doi mdi cong nghe san xuat nudc tuong.
nham dam bao chat lugng ve ATVSTP cho ngudi tieu dung doi vdi san pham nudc tuong.
Doi vdi quy trinh san xuat nudc tuang len men co truyen, sau qua trinh nuoi moc tuong, khoi moc tuang dugc bo sung nudc muoi co nong dp cao (13-15%), sau do dugc il len men trong thdi gian dai. Do qua trinh phoi Iron trudc len men, moi trudng hoan toan khong thanh triing, vi vay se c6 rat nhieu tap chat vi sinh vat nhiem trong khdi dich Ien men nhu: Mi- crococcus, Streptococcus, Lactobacillus, Bacillus va mpt vai dang khac. Mgl so Irong so do se chet chi sau 1 -2 ngay Ien men do anh hudng ham Iugng muoi cao cua dich len men, mdt so tdn tai phat trien trong d6 CO mat cua cac vi sinh vat gay huang, tao cho san pham co huong vi tham dac tnmg [1], [2]. Tuy nhien, trong quy trinh nay, do sii dung cac chung nam mdc CO nguon goc tu nhien vdi hoai lye enzyme chua cao, cac vi sinh vat tao huong nhiem vao khoi dich len men vdi so Iugng te bao khong cao, kha nang lap nhiem de xay ra. Do vay, san pham tao ra theo phuang phap Ien men truyen thdng.
khi san xuat ldn thudng doi hoi thdi gian dai, dp ngpt dam dat khong cao do qua trinh thfly phan chua triel de, huong vi tao ra khong co mui thom manh, dac trung nhu qua Irinh thfly phan bang axit, kho quan Iy qua trinh Ien men do miic dg tap nhiem luon xay ra [4], [8], [9].
Trong qua trinh san xuat nudc tuong Ien men d quy mo cong nghiep, ngudi ta thudng bd sung chii dpng che pham bao tir moc giong (lane koji) co hoat luc en- zyme protease cao, thdi gian ihuy phan nhanh [3], 14]. Doi vdi cong doan Ien men, cac vi khuan va nam men co Igi cho qua trinh Ien men, tao huang vi tot cho san pham nhu vi khuan lactic, nam men Zygosaccharomyces sp. dugc bo sung chii ddng nham tao ra san pham nudc tuong CO chat lugng cao, on djnh ca ve dinh dudng, cam quan, an loan ve sinh thyc pham. Nam men Zygosaccha- romyces sp. phat trien manh d dieu kien pH Ihap, tao ethanol, cac esters, axit hiiu CO, aldehyte, franones va mgt vai thanh phan khac tao nen hucmg vi dac tnmg cua nudc cham [5], [6].
Trong giai doan len men ban dau co bo sung vi khuan lactic, can khong che giam tir tir pH mdi trudng, nham tao mdi trudng thuan lgi cho he enzyme protease hoat dgng, bang viec bo sung chu dpng loai vi khuan lactic sinh acid cham, hoac giam nhiet dp Ien men. Khi pH moi trudng dat tir 4,5-5.0, che pham Zygosac- charomyces sp. da dugc nuoi cay trudc dugc them vao dich len men nhu la giong khdi dpng. Sau do nhiet do qua trinh Ien men dugc tang Ien de qua trinh Ien men rugu dien ra manh me. Khi qua trinh Ien men rugu ket thuc, giam nhiet dp len men va tang tru- trong 2 thang. Co the thay. vi khuan lactic va nam men chju muoi dong vai tro quan trpng anh hudng den huong vi san pham [7].
23
TC.DD&TP9(1)-2013 De cd the irng dyng quy trinh Ien
men nudc tuang cho san xuat quy mo cong nghiep, thay the quy trinh san xuat SU' dyng hoa chat, chiing loi dS nghien ciru cai tien va lieu chuan hoa quy trinh cong ngh? cung nhu hp Ihong thiet bj san xual nudc tuang nham tgo ra san pham nudc tuang co huang vi thom ngon tot cho siic khoe ngudi lieu dung, dam bao vp sinh an loan thyc pham, CO the de dang iing dung cho cac CO sd san xuat hipn nay. Trong bai bao nay, mpt so ket qua nghien ciiu irng dyng nam men, vi khuan tao huong, vj phil hgp cho san pham nudc cham bo sung chu dgng vao qua trinh len men da dugc de cap ldi.
IL NGUYEN LIEU VA PHUONG PHAPNGHIEN ClTU
2.1. Nguyen lieu
- 01 chimg nam men sinh con, chiu muoi cao (Zygosaccharomyces sp.
Z2.8) va 02 chung vi khuan lactic sinh acid lactic, chiu muoi cao (Lactobacil- lus platarium LM 5 va Lactobacillus halophilus LM 7) dugc cung d p tu Bp Suu tap Giong vi sinh vat cong nghiep ciia Vien Cdng nghiep thuc phim
- Dau tuong; sfl- dung dau tuong cua My dang hat nho, kho, khdng co tap chat, moi mgt, khong moc
- Gao; gao nep viing Thai Binh, khong cd tap chat, mdi mgl, khong moc
- Kho dau tuong, liia my: nhap khiu tu My do cong ty EAC cung d p
-Mu6i: su dung muoi hat, dugc bao quan it nhll 6 thang dl lach bdt cac tap chat. Trudc khi sii dung, muoi dugc pha trong nudc vdi ty le nhit dinh dl lang, tach can, vdt bgt trudc khi phli trgn.
Hoa chat phan rich va hoa chit
mdi trudng: co xult xii tir Dire, Nhat Ban, Trung Qudc...
2.2 Phiro-ng phap nghien ciru 2.1.1. Phirmtg phdp phan tich hda - pH dugc do bing thilt hi do pH cam tay.
Axit tdng sd dugc tinh theo phuang phap chuan dp axit - baza, NaOH 0.IN.
Axit amin dugc xac djnh theo phuang phap chuan dg formol.
- NH3 dugc xac djnh theo phuong phap chung cat.
Protein dugc xac dinh theo phuang phap xac dinh lugng Nita tong (phuang phap Kjeldahl).
- Dudng khir dugc xac dinh theo phuong phap axil dinilrosalicylic ( DNS)
- Con dugc do bang thiet bi do dp con Salleron Dujardin Paris
2.1.2. Phu-ang phdp cong nghe - Phuang phap nudi koji; Yz so dau tuong dugc ngam qua dem, vo sach, sau do hap d 115'C trong 60 phut. Yi s6 dau tuong cdn lai dugc rang d 1 SCC trong 20 phut, xay nhd, sau dd phli trpn cung dau tuong hip sao cho ly le am dat 42%. Phoi trpn mdc gilng vdi ty Ie 0,35g/kg. Dan dlu khdi nguyen lieu trong cac khay go chilu cao 6 cm.
Nuoi mic d dai nhiet tir 25-35"C, do am bao hda.
Phuang phap Ien men; Sau khi nuoi. khoi moc dugc bl sung nudc muoi vdi ty Ie 1:2, ham Iugng muoi dat 13%, sau 1 thang dieu chinh muii ve 15%, nudi d nhiet do SCC. Khuly Iron 15 phut/ lan/ngay. Tan suat khuly trpn, trong thang dlu cii 1 ngay khuly trpn 1 Ian, thang thir hai 3 ngay khuly Iron 1 Ian, thang thu- ba trd di 5 ngay khuly trgn I ian.
24
TC.DD&TP9(1)-2013 - Bo sung chl phim vi khuin
gilng dang dich vdi ty U 105 cfu/ml sau 5 ngay I^n men. Sau 10 ngay Ien men rilp tyc bl sung chl phim nim men gilng dang dich vdi ty le 104 cfu/ml.
2.1.3. Phuffng phdp cdm quan Sir dung phuang phap cho diem.
IIL KET QUA VA BAN LUAN 3.1 Nghien cvu bo sung cac che pham nam men sinh rupu, vi khuan lactic trong qua trinh len men.
Chung tdi tien hanh nghien ciru xay dyng quy trinh san xuat nudc tuang theo phuang phap Ien men qua cac cong doan : nuoi moc tao khoi koji CO ham lugng enzzyme thuy phan protein cao, u len men trong nudc muoi cd bo sung cac che pham vi khuan LAB va nam men sinh rugu, lgc, thanh trflng, hoan thien san pham. Trong bai bao nay chung toi gidi thieu cac ket qua trong nghien Cliu bo sung cac che pham vi khuan lactic va nam men sinh rugu nham nang cao chat Iugng san pham nudc tuang san xuat theo phuong phap len men. Cac che pham giong khdi dpng nam men (Zygosaccharomyces sp.
Z2.8) va vi khuan (Lactobacillus platarium LM 5) da dugc nghien ciiu va san xuat tai Vien Cong nghiep thyc pham co kha nang chiu nong do muoi cao (13-16%), co kha nang len men con, Ien men lactic phii hgp vdi qua trinh len men nudc tuong. Quy trinh san xuat nudc tuang Ien men tir vi sinh vat da dugc xay dyng va thu nghiem san xuat d quy mo IOO lit.
3.2 Ngtiien cihi thdi dilm thich hgp bo sung cac che phim vi sinh v^t trong qua trinh ten men nuo^c tirorng.
Trong giai doan dau qua trinh len men, do hoat dgng cua he enzim trong dich len men, cac thanh phan nhu protein, tinh bpt trong khli dich dugc chuyen hoa dan thanh cac dang amino acid, peptide, dudng. Sau thdi gian thfly phan khoang 3-5 ngay, bit dau giai doan phat trien cua cac loai vi khuan lactic chiu mudi, vi khuan phat trien tao cac dang acid hiru co, lam giam gia tri pH dich thfly phan (tdi pH 4,5), tao co h6i cho nam men Zygossacharomyces rouxii chiu muoi, lao con phat trien. Nam men Zygossacharomyces phat trien sau vi khuan, tao con va mpt so thanh phan huong nhu esters, cac axit hu'u ca, aldehydes, franones... , lao nen huong thom dac trung cua san pham nudc luong len men.
Tir cac chung vi khuan lactic da lya chpn phu hgp cho san xuat nudc tuang, chung toi tien hanh nghien Cliu thdi diem thich hgp bo sung cac che pham vi khuan lactic va che pham nam men Zygossacharomyces trong qua trinh len men. Chat lugng dich Ien men sau 3 thang dugc phan tich. Ket qua thi nghiem dugc the hien tren bang 1.
Tu ket qua qua thi nghi$m nhan thay, viec bo sung chu dpng che pham vi khuan lactic va nam men sinh con co tac dpng tot ldi chat lugng dinh dudng va chat lugng cam quan cua dich Ien men. Chiing toi da lya chpn thdi gian thich hgp cho qua trinh len men co bo sung nam men va vi khuan chiu muoi nhu sau: sau 5 ngay len men bo sung vi khuan lactic giong, sau do 10 ngay tiep tyc bd sung che pham nam men giong Zy- gossacharomyces.
25
TC. DD &TP9(1)-2013 Bdng I. Anil hirdng ciia Ihdi gian bo sung che phdm giong nam men vd vi lihuan lactic trong qua trinh len men nu'dc luo'ng
Ten mau
Mlu 1 Mau 2
" "N' Amin j g / i )
12,1 13,2
" ' N long
15,4 16,1
Dirong khir (g/l)_
76,1 77,5
Chai lirgng djch 1 Axil Elhanol t6ng (g/l) (g/1)
1,1 0 1,2 0
len men
Cam quan Mau vang nau, Ihom hai ngai,
CO vang Irang, vi ngpl Mau nau canh dan, thom,
vj ngpt hai chua Mau 3 14,3 16,9 72,6 1,2 1,2
Mau 4 14.2 16,6 74,1 1,2 0,8
Mau nau canh dan, tham miii tucmg, V} ngpt dam, co hau vj Mau nau canh dan, thom diu, vi ngpt, CO nhiem vang trang 3.3 Nghien c u u ty le giong thich
h g p cac che p h a m vi sinh vat bo sung t r o n g q u a trinh len men n u o c tirang
Ty Ie giong bo sung vao djch Ien men ta yeu to quan trpng can nghien cuu. Ty Ie giong thap de dan den vi sinh vat bo sung khong phat trien dii so lugng thich hgp de Ian at dugc cac vi sinh vat lap nhiem, dong thdi bl lie che bdi chinh cac dieu kien khac nghiet ciia moi trudng dan den ty le song cfla cac te bao cac
chimg vi sinh vat bd sung chii dpng giam dang ke, khong con tac dung co lpi n h i m nang cao chat Iugng che pham.
Neu bo sung ly Ie cao qua, dan den gia thanh san pham tang len. dong thdi chat Iugng cua san pham thay doi theo hudng khdng cd lgi.
Tien hanh thi nghiem vdi cac ty Ie bo sung khac nhau cfla vi khuan LAB va nam men sinh con chiu mudi. Ket qua thi nghiem dugc the hien tren bang 2.
Bdng 2. Anh hu&ng ty le bo sung vi khudn LAB, ndm men t&i chdt lirgng nu&c tuffng Chat lupng djch len men
Dudng Axit Mau(cfu/ml) N N
amin long khir long (g/1) (g/l) (g/l) (g/1)
Ethanol
(g/l) Cam quan
Khong bo sung 12,2 15,3 73,4 0,9 Tham, hai ngai, mau vang nau, ngpt, CO vang tring 0.9 Tham dju dac Uung tuong, vi ngpl,
hai nhiem vang nam inen:104
LAB: 105
13,2 16,3 72,2 16.5 72,6
. . Thom diu, dac tnmg ciia tuong, mau nau canh dan, vi ngpt dam, co hau vi Thom miii nudc tuang, hai soc, vi ' ngpt, CO hau vi, mau nau canh dan 26
T C . D D & T P 9 ( 1 ) - 2 0 1 3 Kel qua chi ra rang viec bo sung qua
nhieu vi khuan LAB khong anh hudng nhieu tdi chat lupng cam quan, chi s6 pH san pham giam. Tuy nhien klii tang nong dp che pham giong nam men, chat lugng cam quan bi anh hudng nhieu do ham lugng rugu c6 trong san pham tang. Tir so lieu thu dugc chung toi lya chgn ty Ie bd sung vi khuan gidng lactic la 105cfu/ml va nam men giong la 104 cfu/ml.
3.4 Ket qua thir nghiem len men nirdc tu'ong d quy mo 1001/me
Tir cac ket qua nghien ciru da thu dugc, tien hanh len men thir nghiem nudc tuong khong bo sung vi sinh vat va co bd sung che pham vi sinh vat giong co lgi quy mo 100 lil/me. Cac dieu kien nuoi koji va Ien men dugc thyc hien nhu da ghi d phan phuong phap. Che pham vi khuan. nam men giong dugc sir dung dudi dang dich. Bo sung che pham vi khuan vdi ty Ie 105 cfu/ml sau 5 ngay len
men. Sau 10 ngay Ien men tiep tuc bd sung nam men lao con vdi ly Ie 104 cfu/ml. s a n pham dugc phan lich sau 3 thang len men. Ket qua phan tich thanh phan dich Ien men dugc chi ra trong bang 3.
Kel qua phan lich cho thay khi bo sung che pham nam men va vi khuan lactic da iam tang nong dp con len 0,12 % va acid long so len 2,65g/I. Ty le protein va acid amin cung tang len ro ret so vdi mau khdng bo sung che pham. Chai lugng cam quan cua mau bo sung lot han mau khong bo sung. Trong mau bo sung che pham nam men va vi khuan lactic khong xuat hien vang trang trong qua trinh Ien men. Dieu nay chimg to viec bo sung che pham da han che cac vi sinh vat nhiem lap trong qua trinh Ien men giup san pham an toan han, dong ihdi lao huong vi tham ngon hem so vdi mlu khong bo sung cac che pham giong khdi dpng nam men sinh ruou va vi khuan LAB.
Bdng 3. So sdnh chdt luffng len men giu-a phuang phdp khong bd sung LAB, nam men vd bo sung LAB, ndm men trong lin men nu&c tuo'ng
Chat lirong dich len men N N Dirdng Axit Ethano
pH Amin tong khir tong I (g/1) (g/1) (g/1) (g/l) (g/l)
Cam quan Khong bo
sung 5,2 12,5 15,6 72,5 1,05 Vi dam, thom ciia nudc tuong len men, hoi hac, co vang trang Phuang phap ^ ^
CO bo sung 14,5 17 70,5 2,65 1,2 Vi dam, miii thorn diu dac trung ciia nuac tuong len men, khong bi nhiem vang trang 3.5 Quy trinh san xuat n u d c t u o n g
bang cong nghe vi sinh
Tren co sd cac ket qua nghien ciiu, quy trinh cong nghe san xuat nudc cham bang cong nghe vi sinh da dugc xay dung tai hinh 1
IV. K E T LUAN
San pham nudc tuang san xuat theo
quy trinh len men co bo sung chu dpng cac che pham vi khuan lactic va nam men sinh rugu dat yeu cau ve chat lugng dinh dudng va ve sinh an loan thuc pham. co huong vj thom ngon dac trung. gan giong vdi cac san pham nudc tuong nhap khau tir Nhat Ban, Han Quoc hien dang ban tren thi trudng. Viec bo sung cac che pham vi sinh trong q u a trinh len men 27
1 TC.DD&TP 9(1)-2013 nudc tuong cung han che dugc su phat
irien ciia cac vi sinh vat lap, tranh nhiem Irflng trong qua trinh len men. Quy trinh
nay cd kha nang ap dung de dang tai cac CO sd san xuat vfla va nho, san xuat theo hudng cong nghiep.
Dgu tucmg
Ngam (6-20h)
Lua my
Rang (180''C/20 phiit)
Hapchin(115"C/60phul) Nghien
Phdi Iron Nuoi Koji
X
(32-35»C trong 24 gia d k 25-30°C trong 48 gio sau)
Phoi Iron nuac muoi (NaCI: 13%
Ty lephoi trpn 2:1)
Len men (T: 30"C)
Hinh 1: Quy trinh san xuat nu'O'C tu-oTlg len men co bo sung che pbkm vi khuin lactic va nam men sinh ruau
28
TC.DD&TP9(I)-2013 TAI LIEU THAM KHAO
1. Vu Phjim Hai, Truong Dinh Tri, Duong Van D6ng, Dam Thanh Binh. Ket qud nghien cim guy trinh sdn xudt nudc chdm len men ddi ngdy, Kit qud nghi&n cmi vd nhimg img dung vdo sdn xudt giai dogn 1981-1985. Vien Cong nghi?p Thirc pham, Bp Cong nghi?p Thyc pham.
2. Nguyin Thi Hi6n (2006). Cdng ngh^ sdn xudt mi chinh va cdc sdn phdn len men cd truyen, , NXB KH&KT Ha Npi.
3. A. Bhumiratana, T.W. Flegel, T. Glin- sukon, W. Somporan (1980). Isolation and Analysis of Molds from Soy Sauce Koji in Thailand. Applied and Environ- mental Microbiology, 430-435.
4. T C. Huang and D. F Teng (1998), Soy Sause-Manufactiiring and Biochemical Change. National Pingtung University of Science and Technology, Pingtung Taiwan.
5. K.I. Iwasakiv(I993). Rapid continuous
lactic acid fermentation by immobilized lactic acid bacteria for .soy sauce produc- tion. Process Biochemistry, 28, 39-45.
6. C. H. Lee (1997). Lactic acid fermented foods and their benefits in Asia. Food
Control, Vol. 8. (5/6), 259-260.
7 F.Leroy and L.D. Viiyst (2004). Lactic acid bacteria as functional .starter cul- tures for the food fermentation industry.
Trends in Food Science and Technology, Vol. 15.67-78.
8. K.L. Ong,, S.A Tan, & H.K. Toh (2002).
Soy sauce a traditional Asian sauce now globalised. Singapore Polytechnic, School of Chemical and Life Science.
9. W.F.M. Roling, A. Apriyatino, H.W.V.
Verseveld (1996). Comparision between traditional and industrial approach soy sauce (Kecap) fermentation in Indonesia.
J.of Fermentation and Bioenginering, 81(3), 275-278.
Summary
STUDY TO SUPPLEMENT LACTIC BACTERIA AND YEAST IN SOY SAUCE PRODUCTION PROCESS FOR HIGHER SENSORY QUALITY Soy sauce is an important and popular spice in the world especially in Asia. The study aimed to develop a production process of fermented soy sauce, which has good quality in terms of nutri- tion, food safety and hygiene, as well as sensory quality. Two strains of yeast and bacteria which are resistant to high salt concentrations (13-16%) were selected and used. They are Zygos- sacharomyces sp. Z2.8 yeast which is capable of alcoholic fermentation and Lactobacillus sp.LM 5 which is capable of lactic fermentation in soy sauce. Lactobacillus sp.LM 5 was inoculated after 5 days of fermentation with ratio of 105cfii/ml. Zygossacharomyces sp. Z2.8 was inoculated after 10 days of fermentation with ratio of 104cfu/ml. The results indicated that products femiented by improvement process (100 liters/batch) have better quality than the products without inoculated starter (bacteria and yeast) (protein : 17 g/l, amino acid : 14 5 g/l, total acidity: 2.65 g / l , total sugar: 70.5 g /1 and ethanol: 1.2%). Products have darker color and more flavors.
Keywords: Lactobacillus plantarum, Zygossacharomyces sp, soy sauce fermentation, food safety, flavor of soy sauce
