Sự biến đổi chất lượng của chè tươi nguyên liệu trong quá trình bảo quản

KHOA HOC CbNG NGH£<br /> <br /> <br /> <br /> s y BIEIM DOI CHAT LUOIVG CLIA CHE TUOI IXIGUYEIM<br /> LIEU TROIVG QUA TRIIVH BAO QUAlM<br /> Do van Chuong^<br /> <br /> <br /> T6MTAT<br /> Xac dinh khoi lupng rieng ciia che tuoi nguyen lieu a cac dp day khac nhau la ca sa cho viec tinh toan dien<br /> tich bao quan nguyfen lieu mot each hpp li. Ket qua nghien ciiu su bien ddi chat lupng cua che tuoi nguyen<br /> lieu trong qua trinh bao quan da cho thay viec keo dai thai gian bao quan khong nhung lam cho chat lupng<br /> che tuoi nguyen lieu giam, tir do dan tai chat luong san pham che den kem ma con lam tang he so K (khdi<br /> lupng che tuoi nguyen lieu can thiet de che bien ra 1 kg che kho ban thanh pham). Sir ton that chat kho<br /> eang Ion (h$ sd K eang tang) va chat lupng che tuoi nguydn lieu suy giam eang nhieu neu thoi gian bao<br /> quan eang keo dai. Qua trinh len chat khdi che trong bao quan ma khong duoc dao ru kip thdi dan tai khdi<br /> che tu sinh nhiet va bdc nong do ho hap yem khi da lam cho la che bi vang lia (che bi ngot); ket qua nghien<br /> ciiu qua trinh lam ngot che da cho thay ham luong tanin giam di so vai ban dau 37,82%, ham lupng chat hda<br /> tan giam 22,70%; ham luong chat kho giam toi 9,20%; enzym polyphenolox'daza khong c6n bieu hien hoat<br /> tinh. Ket qua nghifen cuu nay da giiip cho cac doanh nghiep chu dong dida tiet qua trinh san xult hpp ly dl<br /> lam tang hieu qua kinh te trong qua trinh san xuat kinh doanh.<br /> Tirkhod: Bao quin, che tuoi.<br /> <br /> <br /> LDATVANDE doanh nghiep tinh toln dugc thdi gian bio quin che<br /> tuoi nguyen heu tdi iru, nhlm nang cao chit lugng<br /> D l cd e h l hup tuoi nguydn hdu phuc vu hdn tue<br /> san phIm va lam gilm he sd K trong e h l biln.<br /> cho qua trinh sin xult, hien nay nhilu doanh nghiep<br /> ehl biln e h l khi thu mua che tuoi nguyen heu B. VAT LIEU VA PHUONG PHAP NGHIBU CUU<br /> khdng nhiing dti, ma cdn vugt q u i nang lire san xult 1 V^t U^u nghidn aiu: Nguyen heu e h l tuoi<br /> ciia minh. Khi mua nguydn lieu nhilu, do khdng sin gidng Trung du loai 2 tiieo TCVN 2843- 79 [1] d<br /> xuat kip ndn lugng e h l tuoi cdn lai phii dua di bio Thanh Ba, Phii Thp.<br /> quin. Ngoli ra, vide dilu tilt sin xult khdng nhip 2 Phirong phap nghidn cuu<br /> nhang vi du lupng nguyen lidu thu mua q u i it khdng<br /> dli cho ca sin xult ciing din d i n tinh trang phii bio - xac dinh ham lupng chit h o i tan theo T C V N<br /> 5610-1991 [1].<br /> quin che tuoi. C h i tuoi II loai nguyen heu d l hi giap<br /> nat, di va thay ddi mau sic nlu h l o quin khdng tdt - xac dinh ham lupng tanm theo phuong phip<br /> Khi khdi e h l xly ra hidn tugng di, ngdt thi chit khd chuan dp KMn04ciia Leventall [3].<br /> tiong dpt e h l hi phan gili do hd hip, h i m lugng - Xlc dinh dd am che tuoi blng phuong phap sly<br /> tanin va chit hda tan bi gilm do hi dxy hda hoac nhanh [3].<br /> ehuyin sang nhiing hgp chit khdng tan trong nude<br /> - xac dinh su ton thit chit khd b l n g phirong<br /> [2]; ddng thdi xly ra d c phln irng hda hpc llm gilm<br /> phap can e h l tiroi cd khdi lugng va dp Im xac dinh,<br /> him lupng diep luc td, gilm hoat luc ciia enzym ciing<br /> sau dd cho vao vii xd mln v l d l vIo bio quin d n g<br /> nhu llm gilm d c chit thom trong nguydn heu tii dd<br /> vdi che tuoi nguydn heu, sau d c khoing thdi gian<br /> lam cho pham chit che bi gilm nghidm trpng. Bli<br /> theo ddi sly d i n khdi lugng khdng ddi [3].<br /> bao trinh bIy k i t q u i "su biln ddi chit lugng cua e h l<br /> tuoi nguyen hdu trong q u i trinh b i o quin"; da dua - Xlc dinh khdi lugng ndng d a chd tuoi nguydn<br /> din nhiing k i t luan cd tinh khoa hoc v l miic dd Inh heu blng phuong phip can khdi lugng e h l d d c dd<br /> hudng eiia q u i trinh bio quin che tuoi nguyen heu dly khic nhau trdn 1 m^ [4].<br /> din chit lugng sin phIm II mdt vide cd y nghla rIt - Xlc dinh hoat tinh men theo phuong phip<br /> thilt thuc ddi vdi san xult e h l . Tir dd, giup cho d c Margona [5].<br /> - Xlc dinh h i m lugng chit didp luc (chlorophyll)<br /> ' Trung tam CNSH v^ VSATTP<br /> Tmong D^i hpc Kinh te- Ky thu^t Cong nghi?p theo D. L Xapojnhicdp [6].<br /> <br /> <br /> NONG NGHlfP VA PHAT TRIEN NONG THON - KY 2 THANG 1+ KY 1 THANG 2 - 2011 73<br />  KHOA HOC CbNG NGHfi<br /> <br /> <br /> - Do nhiet dp khdi che blng nhiet kl. tieh hlo quin. Xac dinh khdi lugng ridng cua che<br /> Ul. KET QUA VA THAO LUAN tuoi nguydn heu blng each sii dung hop lap phuong<br /> cd thi tieh lm^ chilu cao ciia hop dupe chia khoing<br /> 1. Xlc dinh khdi lugng ridng d a chi tuoi<br /> each 10, 20, 30, 40...100 cm, che tuoi nguydn lieu<br /> nguydn Udu<br /> dupe cho vao hop mdt each toi xdp tu nhien (khdng<br /> Viec xac dinh khdi lugng che tuoi nguydn len dp) d dp day khac nhau tuong tmg vdi chilu cao<br /> lidu/m^ ciing nhu xac dinh khdi lupng ridng eiia ciia hop. Sau dd can lupng che dl xac dinh khdi<br /> chung d cac dp day khac nhau cd mdt y nghla quan lugng che tuoi (kg/m^ va khdi lupng ridng eiia che<br /> trpng trong qui trinh van chuyen va tinh toln dien tuoi nguydn lieu (kg/m^. Kit qui thi hidn d bang 1.<br /> Blng 1: Khdi lugng ridng c h i tuoi nguydn hdu d d c dp dly Idp e h l k h i c nhau<br /> <br /> Dp day Idp che Khdi lupng khdi lupng rieng<br /> TT Nhan xet trong qua trinh bao quan<br /> (cm) (kg/m^ (kg/m^)<br /> <br /> 1 10 6,4 64,0 Dl dao rii, nang suit rIt thap<br /> 2 15 11,0 73,3 Dl dao rQ, nang suit thap<br /> 3 20 16,9 84,5 De dao ru, nang suit khdng cao<br /> 4 25 24,2 96,8 Dl dao ru, nang suit trung binh<br /> 5 30 32,1 107,0 Dl dao ru, nang suit tuong ddi cao<br /> 6 40 48,3 120,8 Hoi kho dao ru, nang suit tuong ddi cao<br /> 7 50 66,8 133,6 Khd dao ru, nang suit tuong ddi cao<br /> 8 60 86,7 144,5 Khd dao rQ, nang suit cao<br /> 9 80 118,5 148,1 Rat khd dao rii, nang suit cao<br /> 10 100 160,7 160,7 Rat khd dao rii, nang suit rat cao<br /> Kit qui bang 1 cho thIy: khi dp day Idp ehl tang trinh bio quin, dilu nay khdng nhiing dip ling nang<br /> Idn gIp ddi thi lugng chi tren mdt don vi dien tieh suit ml cdn dl ding dIo ru trong qui trinh bao<br /> khdng nhiing tang len gIp ddi ma tang cao hon, vi du quin. Kit qui nghien ciiu da dugc chiing minh qua<br /> d dd day Idp ehl II 10 cm tuong duong vdi khdi thuc tl vdi hieu qui cao.<br /> lupng ehl la 6,4 kg/m^; nhung khi dp dly Idp che 2. Str biln ddi chit lugng d a chi tuoi trong qui<br /> tang len gIp ddi (dp day 20 cm), thi khdi lupng II trinh bio quin<br /> 16,9 kg/m^ tang hon 2,6 lln; nguydn nhan II do Idp<br /> a. Su tieu hao chat khd, su bien ddi chit lupng<br /> ehl cd hidn tugng tu nin xudng llm tang khdi lupng<br /> cua che tuoi<br /> ehl trong ciing mdt don vi dien tich. Bdi vay khi hlo<br /> quin che tuoi nguyen heu ta khdng thi tang dd dly Tai elc co sd ehl biln ehl, mdt dilu thudng hay<br /> Idp che qua Idn vi se gap nhilu khd khan trong qua gap trong san xult dd II lugng chi tuoi nguydn li$u<br /> trinh dIo rii, hon niia vdi lupng chi nhilu se cd hidn thu nhan vl mdt liic qui nhilu, do khdng ehl biln<br /> tugng nen chat, qui trinh hd hip yim khi diln ra kip nIn phii bio quin.<br /> manh. Qui trinh hd hip yIm khi xly ra trong khdi Khi tiln hinh thi nghilm, da lly mau tnmg binh<br /> ehl khdng nhiing tieu hao dudng va chit khd lam ciia che nguyen heu cd dp Im ban diu 77,0%; dimg<br /> cho he sd K (khdi lugng che tuoi nguydn hdu d n can ky thuat (sai sd 0,001 g), can 7 mlu (lap lai 3 lln)<br /> thilt dl ehl biln ra 1 kg che khd ban thlnh pham) lly kit qui tnmg binh, mdi mlu 30 gam che tuoi gdi<br /> tang Idn ml trong ndi bd khdi che cdn sin sinh ra trong vii xd man mdng; sau dd cac mlu ehl dupe<br /> axit hiru co, bi dd llm huong thom cua ehl san pham bio quin cimg khdi ehl dang bao quin trdn mang<br /> kem va vi chua [1, 4]. Vdi khdi lupng ridng 96,8 - vdi dd day 30 cm, d dilu kidn nhidt dp khdng khi 29 -<br /> 107,0 kg ehl tuoi nguyen heu/m^ tuong duong dd 31°C, dp Im tirong ddi khdng khi 80 - 85%. Kit qua<br /> dly Idp che tii 25- 30 cm tren mang phii hgp cho qui till hien d blng 2.<br /> <br /> <br /> <br /> <br /> 74 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 THANG 1 + KY 1 THANG 1 ?o 11<br />  KHOA HOC CbNG NGH$<br /> <br /> Bang 2. Su biln ddi ham lugng chit khd vl tinh chit d m quan d a chi tuoi nguyen h|u tiieo<br /> thdi gian hlo quin<br /> Thoi gian Cac chi tiSu Nhan xet trang thai dot che<br /> TT Bao quan Luong chat kho Ton that C.K so voi Do am aia che<br /> (gib) con lai (g) ban dau (%) (%)<br /> 1 0 6,90 0,00 77,00 Tuoi xanh, non<br /> 2 5 6,77 1,90 76,60 Tuoi xanh, non<br /> 3 10 6,68 3,19 76,00 Tuoi xanh, non<br /> 4 15 6,50 5,79 75,50 Tuoi, kem xanh<br /> 5 20 6,47 6,23 75,00 Kem tuoi<br /> 6 25 6,38 7,54 74,40 Oi, kem tuoi<br /> 7 30 6,28 8,98 74,00 Oi, dom thoi<br /> Qua sd hdu blng 2 ta thIy, khi thdi gian bio khdi lupng che tuoi nguydn heu khi dua vao chi biln<br /> quan d n g dai thi tidu hao chit khd eang Idn. Su ton dl thu dupe mdt don vi ehl khd. He sd K cho bilt<br /> that chit khd ciia che nguydn lieu trong qua trinh d n khdi lugng ehl tuoi nguydn heu bao nhidu trong<br /> bao quin da dupe nhilu nha khoa hpc chtmg minh, qua trinh ehl biln dl thu dugc che khd ban thanh<br /> chu ylu la phan huy dudng trong qua trinh hd hap. pham cd khdi Iiiong la 1 kild gam. Trong qua trinh<br /> sin xult, ehl bien vl kinh doanh ehl, he sd K eang<br /> Nlu bao quan tdt, qui trinh hd hip la bilu khi: nhd d n g tdt; nhvr vay su ton thit chit khd ciia chi<br /> CgHisOe + 6 02-)-6C02 + 6H2O + Q (674Kcal). tuoi nguyen Ueu trong bio quin da lam Inh hudng<br /> Nlu bao quin khdng tdt, qui trinh hd hip la tdi he sd K, su ton thit chit khd d n g nhilu thi hd sd<br /> yem khi: K eang Idn, cdng thiic tinh hd sd K nhu sau:<br /> CeHizOg -> 2C2H5OH + 2CO2 + Q (28Kcal).<br /> (100-W2)xlOO<br /> Nhu vay cl hai qua trinh diu cd su phan buy<br /> K: [4]<br /> dudng, nhung nlu hlo quin khdng tdt, qui trinh hd<br /> hip la yIm khi sinh ra rugu, tir rugu phan buy thlnh (100-Wi) (lOO-a)<br /> axit lam cho che ed vi chua, gay Inh hudng xlu din Trong dd: Wj la dp Im ciia che tuoi (77,20%); W2<br /> chit lugng sin pham. Sd hdu bang 2 cho thIy che II dp am ciia che khd bin thlnh phIm (thudng II<br /> tuoi nguydn hdu khdng ndn bio quin qui 10 gid bdi 4%); a: LI he sd hao hut chit khd trong qui trinh hlo<br /> sau khoang thdi gian nly lugng chit khd hao hut Idn quin va ehl biln; a = ai+ a2. Trong dd: a^. LI he sd<br /> hon 5% so vdi nguyen lieu ban diu va chit lugng d m hao hut chit khd trong qua trinh hlo quan; a2: LI hao<br /> quan che ciing kem tuoi, xanh. Dilu nay Inh hudng hut chit khd trong ehl biln nhu qua trinh hlo, vd,<br /> rat Idn din chit lugng che thanh pham sau nly. len men va sly (nlu llm dung ky thuat thdng thudng<br /> b. Su bien ddi he sdK tiong qui tiinh bio quin a2 = 2,0)[4].<br /> vi che bien Thay sd hdu ty Id hao hut chit khd (hd sd a^ d<br /> He sd K la mdt chi tidu kinh tl rIt quan trpng blng 2 va cac sd Udu trdn vao cdng thiic tinh hd sd K.<br /> tiong qua trinh ehl biln ehl ndi chung, nd II ty Id Kit qui thi hidn d blng 3.<br /> Blng 3. Su thay ddi hd sd K theo thdi gian bio quin<br /> Thai gian bao Hao hut chat kho trong Hao hut chat kho trong bao<br /> TT H6 so 100- a H^sdK<br /> quan (gib) bao quan - a, (%) quan va chi biln a = a,+ aj (%)<br /> 1 0 0,00 2,00 98,00 4,26<br /> 2 5 1,92 3,92 96,08 4,34<br /> 3 10 3,21 5,21 94,79 4,39<br /> 4 15 5,78 7,78 92,22 4,53<br /> 5 20 6,27 8,27 91,73 4,55<br /> 6 25 7,40 9,40 90,06 4,60<br /> 7 30 9,00 11,00 89,00 4,69<br /> Sd hdu ciia blng 3 cho tiily khi thdi gian bio tang, vi du khi bio quin 10 gid he sd K II 4,39,<br /> quan ehl tuoi nguyen heu eang dai thi he sd K d n g nhung khi hlo quin tdi 30 gid tiii hd sd K tang Idn la<br /> <br /> <br /> NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 THANG 1+ KY 1 THANG 2 - 2011 75<br />  KHOA HOC CbNG NGHfi<br /> <br /> 4,69; do la dilu bat Igi cho qua trinh sin xult kinh nhilu Idn, sau mdt thdi gian llm cho tl bao II bi dap<br /> doanh. hang loat, nude trong cac md la thoat ra va dpng lai<br /> 3. Quitinnhhu hdng (ngdt) chi tuoi tren II che. 6 dilu kien nly trong dpt che xly ra<br /> Trong qui trinh van chuyin che tuoi nguydn heu hIng loat cac phln ling sinh hoi, phan ling phan buy,<br /> vl CO sd ehl biln ciing nhu tai co sd chi biln do bao phln ling kit hgp, v.v. gay Inh hudng xlu cho chat<br /> quin sai ky thuat, khdi che khdng dugc dIo ru kip lupng ciia che tuoi, mlu sic la ehl bi dd, khdi ehl co<br /> thdi. Cl hai qui trinh nly llm cho khdi ehl hi hd hip mui chua ta gpi la che hi ngdt Kit qui phan tich che<br /> yIm khi, lugng nhidt smh ra trong qiia trinh hd hip tuoi nguyen heu hi ngdt hpin toan dupe thi hidn d<br /> khdng duge tholt ra ngoai m l ngay d n g tich tu blng 4.<br /> Blng 4. Str biln ddi chit lugng chi ngdt so vdi chi tuoi nguydn Udu<br /> Cac chi tieu chat luong cua che<br /> Nhiet dp khdi Dp am cua Chlorophyll<br /> Trang thai khdi che Chat kho Tanin CHT H.T.Men PFO<br /> che C O che (%) tdng sd<br /> (g) (%CK) (%CK) (ml KIO3 0,01 N)<br /> (mg/g CK)<br /> Che tuoi nguyen lieu 24,5 78,0 6,660 33,58 45,47 3,522 0,55<br /> Che ngdt 58,0 72,0 6,041 20,88 35,15 0,332 0,00<br /> Giam so vai ban dau d a<br /> -136,73 7,69 9,29 37,82 22,70 90,57 100<br /> che ngdt (%)<br /> Ghi chii: Men (enzym) PPG: Li men polyphenoloxidaza.<br /> Qua sd lieu blng 4 ta thIy him lugng tanin gilm IV. KET LUAN<br /> di 37,82%, him lupng chit hoi tan gilm 22,70% so vdi 1. Bio quin tren mIng d dd dly lap che tir 25- 30<br /> ban diu. Sir gilm ham lupng tanin din din gilm ham cm tuong duong vdi ty trpng 96,8- 107,0 kg/ m^ la<br /> lupng CHT chi cd mdt phln nhd tham gia vao phan phii hpp.<br /> ling sinh hoa tao mau cho ehl luc diu, cdn chii ylu<br /> 2. Trong qua trinh bio quin chd tuoi nguyen lidu<br /> tanin kit hgp vdi protein chuyin sang trang thai<br /> ed su hao ton chit khd, su hao ton eang nhilu nlu<br /> khdng tan [2].<br /> thdi gian bio quin d n g dli, din din hd sd K eang<br /> Him lugng chlorophyll gilm 90,57% so vdi tang va chit lugng che eang gilm. Thdi gian bao<br /> ban diu. Chii ylu do trong mdi trudng hd hip yIm quin tdi uu khdng ndn qui 10 gid.<br /> khi, d c dudng phan huy thlnh rugu, sau dd rugu<br /> 3. Khi van chuyin, bao quan sai ky thuat ehl se<br /> phan buy thanh axit [2]. Dudi tac dung d a nhidt do<br /> bi ngdt Khi che bi ngdt hoan toln, him lugng mdt sd<br /> vl trong mdi trudng axit cua dich bao, mpt mat<br /> chit gilm di so vdi him lugng ban diu nhu chit khd<br /> protem bi ddng tu lam phi huy vd tl bio, mat khic<br /> gilm 9,29%, tanm giam 37,82%, chat hoi tan gilm<br /> hdn kit giiia chlorophyll va protein bi diit, llm cho<br /> 22,70%, chat didp luc (chlorophyll) gilm 90,57%, hoat<br /> chlorophyU dl tham gia phln ling vdi axit tao ra<br /> tinh men PPO bi gilm holn toln.<br /> pheophitin cd mlu xanh d Uu [2,3].<br /> TAI L i u THAM KHAO<br /> Men PPO khdng cd bilu hidn hoat tinh,<br /> chiing td dudi tic dung ciia nhidt dd va axit, phan bi (1) Bd Ndng nghidp vl PTNT. Vu Khoa hpc<br /> protem trong men hi biln tinh. Cdng nghd vl Chit lugng tiiuc phIm (2001). TuyIn<br /> tap tidu chuan Ndng nghidp Vidt Nam, HI Ndi 2001.<br /> Ham lupng chit khd gilm tdi 9,29% do su<br /> phan huy dudng vl nhilu hgp chit hiiu co khic [3]. (2) Ngd Htm Hgp (1995). Hda sinh ehl. Trudng<br /> Dai hoc Bich khoa HI Ndi, 1995.<br /> Do vay, phii su dtmg d c bidn phip tich cue<br /> trong qui trinh van chuyin vl bio quan che tuoi (3) Vu Thy Thu va nnk. (2001). CIc hgp chit<br /> nguydn heu d co sd ehl biln dl trinh hien tugng llm hoi hpc cd trong che. Nhl xult bin Ndng nghidp, Ha<br /> ngdt che. Trong nhiing trudng hgp cd ty le che ngdt Ndi 2001.<br /> nhilu, ta Jdidng nIn dua vIo ehl biln gay anh hudng (4) I. A Khdti-dlava (1985). Ky tiiuat chi biln<br /> xlu din chit lugng san pham. che. NXB Ndng nghidp, HI Ndi ,1985.<br /> <br /> <br /> <br /> 76 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 THANG 1+ KY 1 THANG 2011<br />  KHOA HOC CbNG N G H i<br /> <br /> <br /> (5) MaprHa (1964). GnpeaejieHHe 4)epMeHTH0H (6) Jl. H. CanoKHHKOB (1959). OnpeaeneHHe<br /> aKTHBHOCTH nojiH^jeHcti-GKCHaasbi B pacTeHHH. Crp 9-11 coflep>KaHH5i x;iopocj)H.njiOB A, B (})H3HojiorH5i pacxeHHS.<br /> BHOXHMHH, T.229-B.3.1964. r.6, B.3. cTp.376.1959.<br /> <br /> <br /> THE VARIATION OF QUALITY FRESH TEA RAW MATERIALS DURING PRESERVATION<br /> Do Van Chuoiig<br /> Summary<br /> The determination of fresh tea raw material's specific weight in different thickness as a basic for<br /> calculating the preservation surface of raw material reasonably. According to the research results on the<br /> change of quality fresh tea raw material during preservation has shown that prolonged preservation time<br /> not only to reduce the quality of fresh tea, but also increases the coefficient K (weight of fresh tea raw<br /> materials needed for processing 01 kg of dried tea semimanufactured product), which makes product<br /> quality of less than black tea. If the longer time for preservering, the quality of fresh tea raw material was<br /> reduced more and the loss of dry matter greater than ( the K coefficient is more increasing). During<br /> preservation if the tea was not upset, shake in time, the cubic mater of tea will themselves generate heating<br /> and vaporize due to lack of oxygen and make tea leaves are yellow (tea will addle). According to the<br /> research results of tea process is addled, it shows that the content of tannin is reduced 37.82% in<br /> comparison with initial; the content of dissolving matter is reduced 22.70%; and the content of dry matter is<br /> reduced 9,29%; the enzym polyphenoloxidaza could not catalyse. The results of this research has<br /> supported the company's initiative to regulate the reasonable production process to increase the<br /> economical efficiency in production process and buniness.<br /> Key words: Preservation, fresh tea.<br /> Ngudi phln bidn: TS. Nguyin Manh Diing<br /> <br /> <br /> <br /> THONG BAO<br /> V^ vi^c xuat ban sd chuyfen d^ giong cSy trong, v$t nu6i v l<br /> chuy6n d^ v6 bi^n ddi khi h l u trong nong nghidp v l PTNT n l m 2011<br /> <br /> Nam 2011 Tap ehi Ndng nghidp va PTNT du kiln se xult ban 03 sd ehuydn dl sau:<br /> - 01 ehuydn dl vl biln ddi khi hau trong ndng nghiep va PTNT. Ndi dung bai vilt la cac kit qua<br /> nghien eiiu khoa hpc, bli tdng quan phln anh tie ddng cua biln ddi khi hau va cac giai phap ling phd<br /> ddi vdi biln ddi khi hau din san xuat ndng nghidp va PTNT (bai giii vl tda soan Tap chi trude ngay 01<br /> tiiang 4 nam 2011).<br /> - 02 sd ehuydn dl gidng cay trdng, vat nudi. Ndi dung bli vilt la cac kit qua nghidn ciiu khoa<br /> hpc mdi vl khIo nghidm va binh tuyen, chpn tao gidng cay trdng, vat nudi (bai giii ve tda soan Tap chi<br /> sd thir nhlt trude ngly 01 thang 5 nam 2011. Sd thii 2 trude ngay 01 thing 11 nam 2011).<br /> Tap chi Ndng nghiep va PTNT thdng bao dl cac cdng tic vien tham gia vilt bai dang tren d c sd<br /> chuyen dl tidn. Bin thao gui dang gdm 01 ban in chinh va 01 ban dien tii (dia CD hoac gui thu dien tii).<br /> Bai vilt theo diing quy dinh " thi Id vilt va giii bai" cua Tap chi Ndng nghiep va PTNT.<br /> Rat mong dugc su cdng tac ciia quy ban dpc<br /> <br /> Dia chi nhan bai: Toa soan Tap chi Ndng nghidp va PTNT<br /> Sd 10 Nguyin Cdng Hoan - Ba Dinh - Ha Ndi<br /> Dien tiioai: 04. 38345457; 04.37711070; 04. 37716634. Fax: 04.37711073<br /> Email: tnpchinongnghiep@vnn.vn<br /> <br /> <br /> <br /> <br /> NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 THANG 1+ KY 1 THANG 2 - 2011 77<br />