Trung binh 1kg nam tuoi cd 0,8-0,9kg nudc, nam rat nhanh ehdng bi cae loai vi khuan, nam mdc phan hiiy.Vi vay, ke tir khi hai den qua trinh bao quan, so che, tieu thu phai thuc hien
Trang 1KHOA HOC VA DOT SONG
QUY TRiNH CONG NGHE CHE BIEN CAC LOAI N A M
Ban tin Khoa hgc vd Cdng nghe xin gidi
thieu den bgn dgc quy trinh cdng nghe chi biin
cdc logi ndm do Trung tdm Cdng nghe sinh hgc
Thuc vat, Vien Di truyen Ndng nghiep thuc
hien Quy trinh da duac chuyen giao cho Trung
tam Chuyen giao cdng nghe vd Kiem dinh, Kiim
nghiem, Sd Khoa hgc vd Cdng nghe tinh Thira
Thien Hue vd dd duac tap hudn cho 5 xa thugc
huyen Phii Vang
I DAC DIEM CHUNG
Cac loai nam an va nam dugc lieu giau chat
dam (protein chiem tdi 25-40% chat khd), cae
acide amin, vitamin, chat khoang va cac chat cd
boat tinh sinh hgc Trung binh 1kg nam tuoi cd
0,8-0,9kg nudc, nam rat nhanh ehdng bi cae loai
vi khuan, nam mdc phan hiiy.Vi vay, ke tir khi hai
den qua trinh bao quan, so che, tieu thu phai thuc
hien theo mdt quy trinh nghiem ngat Mdi loai
nam cd mau sac, hinh dang, cau tao khac nhau
nen khi phoi, say phai dam bao nguyen tac ehung
la: nam giii dugc miii (huong vi) dac trung, mau
sac lu nhien, do am trong nam tir 10-12%o, tuyet
ddi khdng ed nam mdc, vi khuan va cac chat ddc
Id trong nam Nam da phoi, say khd phii hgp vdi
thi hieu ciia khach hang (ngudi tieu dimg) Sau
khi da phoi, say nam khd phai dugc bao quan tdt
de nam khdng bi hu hdng do vi khuan, nam mdc,
dpng vat, cdn trung gay hai Thdi gian bao
quan tdt nhat dam bao tir 12-24 thang nhung nam
van giir dugc chat lugng phuc vu nhu cau tieu
diing ndi dia va xuat khau
n QUY TRINH CONG NGHE
* Hai nam tuoi: Nam phai hai dung do tudi,
khdng de nam phat tan bao tir, nam mdi thu hai,
khdng hai nam sau khi vira tudi nudc xong Thdi
gian ngimg ludi den khi hai it nhat phai dam bao
Iren 4 gid de nam khdng bi dap nat Cac dung cu
hai nam phai sach se ke ca dao keo cat nam bang
inox Trudng hgp nam bi ban do roi, vai, dinh dat,
cat thi phai rira sach, dl rao nudc Tir liic thu hai
den luc che bien khdng qua 24 gid
* Lira chgn phan loai: Nam hai xong can phai cat bd sach phan gdc tach cac cay nam khdi cum (neu la cay nam mgc thanh cum) Tiiy thudc vao timg ddi tugng cu the ed the rira hoac khdng rira khi hai xong Nam sd khdng can rira, mdc nhT neu rira sach thi cang tdt, nam ram chi rira nhiing cay nam bi ban; linh chi bat budc phai rira sach Khi hai xong can loai bd nhiing nam sau, nd Tiiy theo yeu cau cua thi trudng tieu thu san pham ma nam
cd the dugc cat to hay nhd hoac de nguyen cay nam Thdng thudng nam sd cd the xe thanh 2-3 manh ddi vdi nhirng canh nam ldn (dudng kinh 4em trd len); linh chi cd the thai lat mdng hoac de nguyen, mdc nhT de nguyen cay
* Nam mudi (danh cho nam rom): Nam rom sau khi thu hai lam sach va phan thanh timg loai Thir nhat la luge nam trong nudc sdi, viia luge vira an chim nam trong nudc, thdi gian dun sdi trd lai cang nhanh cang tdt Tiiy theo nam nhd hoac
to, luge nam tir 5-7 phut (tiiy theo kich thudc nam) d nhiet do lOO^C, tinh lir lue bat dau sdi trd lai va yeu cau nam phai chin Thir hai la lam lanh, sau khi luge nam dii thdi gian lien hanh vdt nam
ra lam lanh bang each thay nude nhieu lan hoac cho chay lien tue dudi vdi nude Bieu hien nam chan chin: nam chim trong nude lanh, lam lanh cho tdi khi nhiet dp ciia nam va nudc bang nhau thi tien hanh vdt ra de mudi nam
Ludc xong de rao nude, pha dung dieh nudc mudi bao hda (Hit nude eho khoang 0,4kg mudi), dung dich nudc mudi dat 22-23'^ Bome la dugc, cho tiep 10-15g axit Citric vao dung dich nudc mudi sau dd eho nam vao (pH 3,5- 4) 1kg nam da ludc cho vao 0,2 lit dung djch nudc mudi va axit
da pha tren ciing eho mdt lop mudi Cho nam da ludc vao thiing nhua hoac tiii nilon khdng thiing, chum vai Sau 15 ngay thi nam mdi dn dinh ve
dp man va mau sac, neu cd hien lugng siii bgt, len men thdi thi phai bd nlu mudi lan bet thi phai bd sung mudi Can chu y la ludn ludn de nam ngap chim Irong dung dich nudc mudi va axil Nam
BAN TIN KHOA HQC VA CONG NGHE THUA THIEN HUE, 4/2011
Trang 2KHOA HOC VA DOT SONG mudi thudng diing lam nguyen lieu de lam nam
ddng hop, cd the bao quan hang nam
* Nam say khd (danh cho nam sd, mdc nhT
va linh chi): Trudc het la each say nam nam sd ed
the xe thanh 2-3 manh ddi vdi nhiing canh nam
ldn (dudng kinh 4cm trd len); linh chi cd the thai
lat mdng hoac de nguyen, mdc nhT de nguyen eay
Neu thdi tiet khdng cd mua hoac ed nang, gid
manh Dem nam trai mdt Idp mdng tren eac vat
lieu thdng thoang (ludi, tre manh, tam phen
thoang ) true tiep tren nen san (be tdng, gach)
hoac de each mat dat 15 cm trd len cang tdt, thdi
gian phoi nang, gid tu nhien khoang 15h trd lai
Neu thdi tiet mua, dung quat gid manh thdi true
tiep vao Idp nam tuoi thdi gian khoang 4-6h
Trudng hgp mat dien, trdi mua thi xep nam vao
khay, dua vao Id say phai say ngay, khi nam da se
khd tien hanh ddn khay ket hgp vdi viec dao deu
Nhiet do say nam khoang 2-3h dau tir 40-45°C,
2-3h sau d nhiet do 45-50°C, thdi gian tiep theo d
nhiet do 50-55°C den khi nam da gan khd tang
nhiet do tdi da len 55-60°C (vai tieng dau can phai
bat cira thdng gid d tde do tdi da sau dd giam dan
tde do khi nam da gan khd) Thdi gian tir liic hai
tuoi den khi phoi, say khd dam bao tdi da 24h (trir
mdc nhT, linh ehi tdi da 72h) Khi say nam trong
Id say phai xep nam khd d tang dudi, tang tren
cimg dung nam cd do am cao nhat tranh trudng
hgp nam da khd (de tang dudi) se hiit am trd lai,
trong qua trinh say phai tien hanh dao khay tranh
d dudi bi chay Khdng de nhiet do trong Id say
qua cao (>50°C) trong 6h dau Khi say nam cdn
do am eao can phai md het cd cira thdng gid phia
dinh Id Nam dat do khd va chat lugng tdt bieu
hien: be tai nam gidn tan, miii thom, vi nggt, mau
vang sang (gan nhu mau eay nam trudc khi phoi,
say) Chii y: Ddi vdi nam linh chi cho phep eudng
dinh mu khoang 3 cm, qua va mii nam dugc cho
vao gian rieng de say
Nam da say khd cho vao tiii nilon (2 lan tiii)
Bude chat timg lop tiii (ke ca bao diia la 3 lan
bude mieng tui), qua trinh thao tac nhe nhang
tranh de nam vun nat Trudng hgp nam say dat
den dp am tuyet ddi (ham lugng nudc trong nam khd bang 0) nam rat de bi vun nat khi va dap Khi lay nam trong Id say ra nen de ra ngoai khoang 5-10 phiit mdi cho nam vao trong bao (ban chat la
de cho nam hut am trd lai dam bao do am tir 10-12 %)) nam se khdng bi vun nat
* Bao quan nam khd: Ddi vdi viec bao quan lau dai thi xep nam trong cac kho sach se, khd rao, dudi nen cd the Idt 1 lop vdi cue de tranh hiit
am, ehdng mdc Sir dung may hiit am trong kho, ddt bdt luu huynh khoang 3 thang 1 lan de ehdng mdc, mdi, mgt, ddng vat gay hai Thudng xuyen kiem tra cac bao dung nam khd, neu thay nam hiit
am (sd tay vao nam khdng thay sdt soat) dem say lai can kiem tra do am trong nam, neu dudi 12% thi phai say nam lai ngay Ddi vdi viec ddng gdi nhd thi tuy theo yeu cau cua khach hang de ddng tiii nam khd theo trgng lugng khac nhau, khi ddng gdi nhd phai that kin Khi sir dung khdng het phai budc that kin mieng tiii nilon
Quy trinh sir dung (an) nam khd tuong tu nhu an nam tuoi Trudc khi an phai ngam nam trong nudc ndng (nhiet do tren 60°C) thdi gian tir
60 phiit trd len, rira sach trong nudc lanh sau dd mdi dimg de che bien
Ddi vdi nam sd ban tuoi, sau khi hai vao, cat chan, loai bd nhiing nam bi nat, gia, nam bi sau, thdi Xep nam vao bao, xep quay gdc vao trong, tan nam ra ngoai, ddng nhan Ddi vdi sd tim dua vao may hiit chan khdng hut bet khdng khi va han mieng bao, bao quan d nhiet do (10-15''C), each nay cd the bao quan nam dugc 7 ngay Ddi vdi sd trang dua vao bao quan d nhiet do 10-15"C (khdng hut chan khdng)
Ddi vdi nam rom thi hai nam dimg do tudi, hai khi nam ehua nirt bao (chieu dai >cbilu rdng), cat chan, loai bd nhirng nam hdng, sirt seo, rach
vd bao Rai mdng ra nen, eho quat gid de lam giam dp am ciia nam sau dd cho vao tiii ludi (khoang 0,5kg) eho vao sgt nhua va van chuyen
ra thi trudng (vdi dieu kien van chuyin xa) Nam rom khdng dugc bao quan trong tii lanh
PV
BAN TIN KHOA HOC VA CONG NGHE THUA THIEN HUE, 4/r>011