Sd Nong nghiip va Phat trien Nong thdn tinh Binh Bui Thi Phuong Loan, Do Thanh Dtnh, Nguyen Thu Dinh.2018. Bio cio tinh binh sin xuat ndng nghiep Thuy, Hoang Thi Ngan, Tran Van The. 2019b.
nim 2017. Cost Benefit Anaiysi.'. (CBA) of Climate Change Quyet dinh Sd: 2663/QD-UBND ngiy 28 thing 7 nam Adaptation Strategies on Crop Production Systems 2015 cua UBND tinh Binh Dinh vl vi|c phe duylt and selected adaptation measures for the crop- quy hogch phat trien trdng trpt tinh Binh Dinh din sector Final Actnin- Report 5 under Project, nim 2020 va dmh budng din nim 2030.
Economic efficiency of intercropping peanut with cassava in Phu Cat district, Binh Dinh province
Do Thanh Dinh, Bui Thi Phuong Loan, Tran \an The, Vu Thi Hang, Hoang Thi Ngan Abstract
Agricultural production in Binh Dinh province plays a pivotal role and has been facing tremendous challenges due to negative impacts of climate change. The intercropping peanuts with cassava in Cat Hiep commune, Phu Cat district, Binh Dinh province was considered as a significant adaptation measure to help farmers reducing the risk and impact of climate change. The result showed that the intercropping peanuts with cassava increased yield of both peanuts and cassava; the average cassava yield reached 23.13 tons/ha, the average peanut v-ield reached 4.19 ton.s /ha; reducing the tost of fertilizer and pesticide use; improving, protecting soil and restraining washout, soil degradation. In terms of economic efficiency, the model of growing cassava with peanut had the revenue of VND 98,615,720 VND/ha, which was 13 times higher than that of cassava monoculture. The study recommends a large - scale deployment of the intercrop model of peanuts with cassava in poorly cultivated, degraded lands and well irrigation.
Keywords: Climate change, intercropping, cassava, peanut, Binh Dinh
Ngiy nhan bii: 20/8/2019 Ngfldi phdn bien: PGS. TS Nguyen Huy Hoang Ngay phin bi|n: 2/9/2019 Ngay duyet dang: 9/9/2019
MAT SO Pseudomonas spp. VA TONG SO VI SINH VAT HIEU KHl T R £ N C A R 6 P H I PHI LE KHI BAO QUAN 6 N H I £ T DQ THAP
Nguyen Thi Kieu Diem'-^, Nguyen Thuy Van Duyen^ Mai Tlij Tuyet Nga' T 6 M TAT
Nghien ciiu n h ^ muc dich theo doi mat so Pseudomonas spp. va tong so vi smh vat hieu khi (TVC) trong qua trinh bao quan lanh ca ro phi phi le cl 5 che dp nhiet dp on dmh (1, 4, 9, 15 va 19 ± 1°C) va 2 che do nhi?t dp bien dpng m6 ph6ng phan cuoi cua chuoi cung ling. Ket qua nghien ciiu cho thay luong TVC trong ca ro phi phi le khi hft lh6i han bao quan d nhiet do 1 ± 1°C la sau 144 gid la 1,1 > 107 CFU/g, 4 ± TC sau 48 gi6 la 2,4 » 106 CFU/g.
Mjt so TVC viipt ngiidng cho phep .sau th6i gian bao quan 6 cac che dp: 9 ± 1 C 24 gid; 15 ± l^C 24 gid va 19 ± 1°C 20 gid tuong ling la 1,47 x 10' CFU/g, 1,83 x 10' CFU/g, 1,28 « 10" CFU/g. Trong khi mat sp Pseudomonas spp. d che dd bao quan 1,4,9, 15 va 19 ± 1 "C tai cac thdi diem 144; 48; 24; 24; 20 gid tuong ilng la 3,62 x 10<; 2,17 . 10';
4,43 X 10"; 2,68 x 10'; 1,55 x 10' CFU/g. 6 2 che dp nhiet dp bien dpng, lupng Pseudomonas spp. va TVC tang khi sif nhiel dp cua moi trildng xung quanh tang. Thdi han sil dung cho phi le ca ro phi dupc bap quan d che dp nhi?t dp bie'n ddng 1 14 dudi 32 gid, d che dp nhiet dp bien dpng 2 la dUdi 50 gid, d cac thdi diem nay lupng TVC nam trong gidi h?n cho phep khi ket thiic qua trinh bao quan {<10* CFU/g).
Til khda: Bao quan lanh, ca ro phi phi le, Pseudomonas spp.. tong sd vi sinh vat hieu khi
I. DAT VAN DE trd thanh mot trong nhiing nganh kinh te mui nhpn Trong nhang nam gan day, nganh thuy san cua cua dat nilcic, dac biet la viing Dong bang song Cilu Viet Nam da co nhOng bildc phat trien manh me. Long (DBSCL). -\Id rpng thi trUdng vi da dang hoa ' Khoa Cong nghe Thuy sin, TrUdng Cao dang Kinh te - Ky thuat Can Thd
^Khoa Cdng ngh? ThUc pham, Tnidng Dai hpc Nha Trang
san pham tfl nhieu doi tfltfng de tao ra nhflng loai san pham co nang luc canh tranh cao tren thi trUdng the gidi Ii mot chien ludc rat can thiet cho sU phat trien cua nganh thiiy san nU6c nhi. Doi tfldng a ro phi {Oreochromis niloticii>) la mpt trong nhflng loai nguyen Ii?u co khi ning dip flng nhu cau xuat khau manh me. O cac nUdc chau Phi, Trung Dong \ a mot so nude tren the gioi, ca ro phi la loai du^c nuoi phd bien nhat khi nguon nguyen lieu ca tfl nhien trd nen can kiet (Ahmed, 2005). Ca ro phi trd thanh nguon protein ehu yeu d nhieu quoc gia phit trien.
Sin lUqJng ca ro phi nuoi tren the gidi la khoang 5,67 tri?u tan nam 2015 (FAO, 2017) va tren 6 trieu tan vio nam 2016, trong do nhflng nfldc san xuat ca ro phi phi Ie nhieu nhat Ii Trung Quoc, Indonesia, Ai Cap, Brazil, Bangladesh, Philippines, Thai Lan vi Vi^t Nam (VASEP, 2017). Tai Vi^t Nam, nim 2015 tong sin IU(?ng ei ro phi tren ci nUdc la 187.800 tan, xuat khau ban 27,5 trieu L'SP (Ha Kieu. 2016).
Theo VASEP, sin lfldng ca ro phi ting qua cic nam, nim 2017 xuat khau diKfc 43 tri^u USD sang 68 th) trfldng, nim 2018 sin Iflpng cd ro phi da d^t 255.000 tan dflng thfl 6 trong cic nUdc sin xuat ca ro phi nhieu nhit tren thegidi (VASEP 2018)
Hi?n nay, phan Idn sin pham thuy sdn xuat khau cua Viet Nam deu d dang dong l^nb. Tuy nhien, khi lieu thu trong nUdc hodc t?i nude nhdp khau, ca dong lanh thfldng dflpc dua den ndi tieu thy. dupc ra dong vi biy bin dUdi dang Udp I^nb, day la luc xay ra sfl sai pham ve nhi?t dp trong qua trinh van chuyen vi hoc dd hang boa cua nha phin phoi, sfl sai pham ve nhi?t do trong qui trinh biy ban va lfla chpn hang eua ngUPi mua 6 sieu thi vi quay ban Ie...
Qua trinh niy tao dieu ki?n eho cdc vi sinh vit phat trien tren san pham giy bfl hong, n6i trpi la he vi sinh vat giy hfl h6ng die trflng (Specific spoilage organism-SSO), cic vi sinh vat niy ton tai vi phit trien tren ci vi cac sin pham tfl ci, sinh ra sin pham cap thap lim giim chat Ifldng san pham (Xing et al, 2012). Died mpt vai nghien eflu phdn lip dupc mpt so vi sinh vat nhfl: Pseudomonas spp.. Photobacterium phosphoreum, Shewanella putrefaciens, Vibrio tren cac loai thuy san. Nhin chung, doi vdi da so san pham thuy sin bao goi trong moi trUdng khong khi va bao quan lanh thi long so vi sinh vit hieu khi phat trien d nhiet dp dfldng thap {T\'(.^), trong do phan Idn Ii Pseudomonas spp., la cdc vi smh vat chu yeu gay nen cic bien doi chat lUpng cua san pham. Do do, nghien cflu mat so cua Pseudomonas spp. va TVC tren phi le ca ro phi vin (Oreochromis niloticus) khi bao quan d nhiet dp thap se cung cap cic dan lieu khoa hpc cho
qua trinh kiem sodt va quin ly chat lUo i.: •' , i " "
phi le ci ro phi vin d cu6i chuoi cung i I L V A T L I E U V A P H L T O N G P H A P N G H I ! • L 2.1. Vat lieu nghien cflu
Ca ro phi phi le: Ca ro phi dupc phi Ic \ .i Jong rcJi IQF (Individual QuickK Freezer) tai mpt cong ty che bien thuy san 6 DBSCL, cd ed 120 -170 g/phi le. Mau nguyen lieu dUde dung trong tui PE (Polyethylene) hin kin mieng vi gifl lanh bang da gel trong thung each nhiet, van chuyen ve phong thi nghiem Trfldng Dai hpc Nha Trang trong vong 16 gid. T^ phdng thi nghi?m, ci dfldc kiem tra, bao goi vio tiii PA (Polyamide) (3 phi le/tui) va bao qudn d -18 ± 2°C den khi sfl dyng.
Hoa chit va moi trUdng: Hda chat vi moi trudng sfl dung gom: Plate count agar (Merck), Pseudomonas base F (Merck), Pseudomonas CFC supplement (Merck), Pepton from meat (Merck), Sodium hydroxide (Trung Quoc), NaCI (Trung Quoc), Na.HP0,.12H,0 (Trung Quoc), K H / O ^ (Trung Quoc).
2.2. PhUdng phap nghien cflu 2.2.1. B6 tri thi nghiem
Ca ro phi phi le trong tui PA dflpc ra dong hoin toan bing khong khi lanh d 6 - 8°C trong thdi gian 8 gid, sau dd cd dupc x^p vao khay xop (1 mieng phi le/khay) vi bpc kin bing ming PE mdng. Cdc khay cd dflpc bio quin d 5 eh^ dp nhiet dp 6n dinh li: 1, 4, 9, 15 va 19 ± I X bang tu lanh gia dyng cd lip thiet bj dieu khien (Dbcell, Emerson Electric Co.) de on dinh nhiet dp trong qua trinh bao quin.
Thdi gian bao quan mau dflpc bo tri dfla tren nghien cflu cua Huynh Thi Ai Van (2015) va Mai Thi Tuyet Nga (2016). 6 moi che dp nhiet dp, lay 7 - 9 diem mau theo thdi gian de theo doi dUpc sfl bi£n dpng cua lupng vi khuan trong suot qua trinh bio quin, tao dieu kien de phdt hi?n dflpc quy luit bien doi (neu cd) cua chi tieu chit ludng nghien cflu (Chill-on. 2007). Nhiet dd cac ngan tu dflpc giam sdt bang bp dieu khien Dixell vi nhi^t ke tfl ghi EC850A (MicroLogPRO II, Israel). Nhiet dp mau dflpc giam sat hen tuc bingnhi?t ke lfl ghi DS1922L-F5 iButton"
(Maxim Integrated Products, Inc., CA) - Md hinh nhiet dp lanh bien dong 1: Phi \t ca rd phi dflpc bao quan a 2 ^he d6 nhi^t dp la l ± ^ c va 19 ± r C luan phien nhau trong sudt thdi gian bao quin. Nhi^t dp bat dau bao quai. la 1 + I^Q ij- . 4 - 6 gid vao ban ngay vi 8 - 10 g,,, vio b a n d ^ m M thayd6inhi?tdp I lan, tien hanh nhu a. jn,
Top chi Khoa hoc Cong nghe Ndng nghiep Viet Nam - S6 9(}06}/20t9 qua trinh bio quin 168 gid. Diy la nhflng nhiet dp
c6 the g^p trong qua trinh bao qudn phi le ea tai sieu thi nhu tai cic kho lanh (I ± I°C) thinh thoang hi md cfla de dfla hang vao va lay hang ra (19 ± PC) quay trUng bay de bdn.
- Md hinh nhiet dp lanh bien ddng 2: Phi le cd rt phi dflpc bio quan d 3 che dp nhiet dp: 4 ± I°C, 9 ± I X , 15 ± 1°C luan phien nhau trong sudt thdi gian bao quan. Nhi?t dp bat dau bao quan la 4 ± I°C, cfl 4 gid vio ban ngay va 8 - 10 gid vao ban dem thi doi nhiet dp mpt lan theo thfl tfl ii 4 ± I°C den 9 ± I^C va 15 ± l^C, tien hanh nhfl viy trong sudt thdi gian bao quan 168 gid. Diy la che dp md phdng nhi?t do t?i tfl trflng bay sieu thi (4 ± I°C, ddi luc cd the li 9 + 1°C), nhi?t do thay doi khi ngfldi mua lay sin pham rakhdi tu vachpn lfla (15 ± 1°C).
2.2.2. PhUdng phdp phdn tich visinh vdt Xic dinh tdng sd vi sinh vat hieu khi (TVC - Total Viable Counts) phat trien d nhiet dp thap theo NMKL 86 4"' ed 2006 (Nordic Committee on Food Analysis) va xac dinh Pseudomonas spp. theo TCVN 7138:2013.
2.2.3. Xdly so lieu
Thi nghiem dflpc tien hanh lap lai 3 lan dpc lip vdi 3 Id ea rd phi phi le. Sd lieu dflpc tinh trung binh, dp l?ch chuan tren 3 lan thi nghiem. Phin tich
phUdng sai {ANO\A) va kiem dmh Tukey dupe thUc hien tren phan mem SPSS 17.0 vdi mflc khic biet ed y nghia a = 0,05.
2.3. Thdi gian va dia diem nghien cflu Nghien eflu dflpc thflc hi?n tfl thing 8 nim 2017 den thing 2 nim 2019 tai Phdng thi nghiem (PTN) Cdng nghe thflc pham, PTN Hda sinh -Vi sinh vi PTN Cim quan thupc Trung tam Thi nghiem - ThUc hinh, Trfldng Dai hpc Nha Trang.
III. KET QUA \ A THAO LUAN
3.1. Bien doi ciia tong sd visinh vit hifu khi (T\'C) phat trien d nhiet dp thap tren phi le cd rd phi d nhiet dp lanh on dinh theo thdi gian bao quan
O che dp bao quin 1 ± l''C mat sd TVC ban dau trong cd rd phi phi le ta 5,3 " lO^CFU/g. Sau 72 gid bao quin, mat sd TVC hau nhu khdng thay doi. Tuy nhien, d 144 gid bio quin m^t sd TVC dat 1,1 • 10' CFU/g, vUdt qua gidi han cho phep cua TVC trong thuy san tfldi can gia nhiet trfldc khi sfl dgng theo quy dinh cua Bp Y te li 10" CFU/g (Bp Y t^, 2007). 6 cie gid bio quan tiep theo: 192, 216, 240 gid mat sd TVC tang len lan lupt la 3,9* 10'; 1,8 x 10'; 3,9 x 10"
CFU/g. Den cuoi thdi gian bio quin 312 gid m^t sd TVCla9,lx 10'CFU/g.
T h n giai bio qiUB (gfa)
Hinh 1. Su bien doi cua TVC tren phi le ca ro phi d cac nhiet do lanh on dinh 1 ± 1"C. 4 ± 1°C
Thai f^ao bio quan (gio^
Hinh 2. Su bien doi eua TVC tren phi Ie ed rd phi d cic nhiet dp lanh on dinh 9 + I'^C, 15 ± rC, 19 ± PC
Ghi chd: d hinh 1 vd 2 tr&n ciing mgt che dd nhiet dd bdo qudn, cdc chU cdi khac nhau the hien sU khdc biet cd y n^ia (p < 0,05) ve mat so cua TVC trung binh giUa cdc gid bdo qudn.
^noanocLdf grj-^ \6ngngi
.Mat sd T\'C cang tang khi nhi?t dp cang cao va nhanh chdng \'Upt ngfldng cho phep. CJ cic nhiet dp bio quin 4 ± I X . 9 ± I X , 15 ± 1 C va 19 ± I X , ci se het thdi gian bao quan tuong flng lan Ifldt la 4,SynM2.4- 10* CFU/g) 24 gid (1,47 X 10* CFU g).
24^10(1,83-10'CFU/g)va20gid{1 :S.10'CFU g) Ket qui phan tich .•\NO\'A eho thay khdng cd su khdc biet y nghia (p > 0,05) ve Iflpng T \ C tnmg binh gifla cac gid bio quan d ca 5 che dp nhiet do bio qudn 1 ± I C , 4 r I X , I5± I C . 19 ± i C Rieng che dp 9 ± T'C lUpng T \ C trung binh tai 1 t'S gid bao quin cd sU khac bi?t y nghia (p < 0,05) so vdi cic gid bao quin cdn lai trong cung che dp.
Tde dp ting cua I VC cing nhanh khi nhi?t dp bio quin cang cao, sfl gia tang niy ddng nghia vdi vi?c glim chat Iflpng cua CA Tfl dd cho thay nen bao qudncirdphiphilednhi^tdp 1 ± I C dUoi 144 gid, d 4 ± I X dudi 48 gid, d 9 ± I C dudi 24 gid; d 15 ± I X dfldi 24 gid, d 19 ± I X dfldi 20 gid de dim bio chat Iflpng cua ca rd phi phi le theo quy dinh cua Bp V te. Ket qui nay tUdng ddng vdi ket qui nghien eflu cfla Mai Nga vi Huynh N'an (2017), nhdm tic gii tim thay ring mat so TVC tren ei Tra phi le vUpt qui ngUdng eho phep khi bdo quan d nhi?t dp 1 ± I X .
noi K-ng n d nhi?t spp. tren 4 ± I X . 9 ± I'C, 15 ± I C . 19 ± I' ^ tfldng flng l i 216; 96; 36; 16 va 7 i;u> \ dai thdi hain bao quin cua CJ rd phi p'"' va hang thuy san ndi chung nen bJ*' . dp thap.
3.2. Bien ddi cua mat sd Pseudomoii phi Ie ca rd phi d nhiet dp lanh dn dinh theo thdi gian hao quan
Tfl ket qua d hinh 3 va 4 cho ihav d che dp bio qudn 1 ± I X mat sd Pseudomonas spp. ban dau li 1,3 K 10^ CFU/g, thdi gian bao qudn cang dai mgt sd Pseudomonas spp. cang tang. O 144 gid bio qudn, mat sd Pseudomonas spp. tang len 4,2 x IO"* CFU/g, d 240 gid bao quan Ii 2.7 x 10" CFU/g. 6 che dp bdo quin 4 ± T'C mit sd cua chung tang nhanh d cdc gid bao quin 48, 96. 120, 144, 192 gid lan lUpt li:
1,6 X lOXFU/g 3,3 X 10* CFU/g, 9,4 x 10' CFU/g.
1,0 X 10" CFU/g, 2,4 X 10" CFU/g. Tai gid bdo quin cudi 240 gid mat so Pseudomonas spp. dat 1,1 x 10' CFU/g. Cdn d cic che dp bio quan 9 ± 1"C, 15 ± I X , 19 + I X , Pseudomonas spp. cd xu hfldng phdt trien manh tfl nhflng diem mau dau, sau dd tang chgm trong suot cic gid bio quin cudi d cd 3 che dp nhi^t dp tren.
Hinh 3. Sfl bien doi ciia mat sd Pseudomonas spp. tren phi le ci ro phi dcac nhict dp lanh on djnh 1 ± l^C va4+ r C
Hinh 4. Sfl biln doi cua mat so Pseudomonas spp. tr^n phi Ie ca r6 plu d cdc nhi?t dp l?nh dn dinh 9 ± 1°C. 15 ± I C , 19 ± 1°C
Ghi chu: d hinh 3 vd 4 tren cung mgt che dd nhiet dd bdo qudn, cdcchQcdi khac nhau ihehten si/ld,- cd y nghia (p < 0.05) ve mat so Pseudomonas spp. trung binh gida cdc gid bdo qudn. "'' '^^
TapchiKhoa noc Cdng nghe \dnq - •Nam-SJ9tl06f/2019 Ket qui phin tich ANOVA cho thay khdng cd sti
khic bi?t y nghia (p > 0,05) ve mat sd Pseudomonas spp. trung binh gifla cdc gid bao quan d 3 che dp nhiet dp bio quin I ± I X , 15 ± I X , 19 ± I X . CJ che dp nhi?t dp 4 ± i X va 9 ± I X , mat sd Pseudomonas spp.
trung binh d gid bao quin cuoi 240 gid (4 ± I X ) vi 192 gid (9 ± PC) cd sfl khac biet cd y nghia (p < 0,05) so vdi cdc gid bdo qudn cdn Iai. Ket qua nay tfldng ddng vdi nghien cflu cua Huynh Thi Ai Van (2015), tic gia cho ring d nhiet dp bao quan l ± l X , 4 ± I X , 9 ± r C , 1 5 ± 1 X , 1 9 ± l ' C p h i l e c d Tra khdng nen bao quan qui thdi gian tfldng flng la 216; 96; 36; 16 va 7 gid.
K^t qud phin tich cho thay mat sd Pseudomonas spp. bien ddi theo quy luat dfldng eong sinh trfldng cua vi sinh v^t, Dieu nay cing chflng td Pseudomonas spp. la vi khuan giy hdng die trUng cua phi le ci rd phi khi bao quin lanh. Chinh vi sfl thich nghi vi phit trien mgnh cua Pseudomonas spp. trong dieu ki?n l?nh, gay hfl hdng eac sin pham thuy sin. Theo nghien cflu eua Huynh Thi Ai Van (2015) va Tran Thi Thu L? (2015) khi nghien cflu ve nhdm vi sinh v^t giy hfl hdng dat trUng tren san pham cd Tra phi le va tdm sfl, nhflng mat hing thuy san ddng lanh
xuit khau chu luc eua \'iet Nam, cac tac gii tha\
ring day la nhdm vi sinh vat thfldng xuat hi^n vi can phdi kiem soat trong qua trinh bdo quan I ^ h mdt sd mat hang thuy sin nhfl: tdm su, phi le cd tra...
3.3. Bien doi cua TVC va mat so Pseudomonas spp.
tren phi Ie ca rd phi d nhiet dp lanh hien dpng 1 Dd thi hinh 5 chi rd sU thay ddi ve mat sd TVC va Pseudomonas spp. tren phi le ci rd phi nim d cuoi qud trinh bao quan. Mat sd Pseudomonas spp.
cao nhat dat 9 x 10' CFU/g (khi bio quin 1 ± I X d 168 gid). TVC dat ngfldng cho phep d mau bao quan 32 gid nhiet dp 19 ± I X (1,37 x 10* CFU/g). Dieu nay co the hieu khi cd sU sai ph?m nhi^t dp tren thflc ted chuoi cung flng, san pham dfldc bao qudn va bay ban d cic tu ddng eua sieu thi, vi^e md tu lfla chpn hang hda cua khich hing dan den sfl thay doi nhiet dp tfl thap (1 ± IX) den cao (19 ± I'C) lim cho mat sd vi sinh vit ting manh vUpt qui ngfldng quy djnh.
Dfla vio ket qua phin tich vi sinh vat tren cd the thay thdi ban sfl dung cho phi le ei rd phi dflpc bdo quan d che dp nhi?t dp md phdng bien dpng 1 khdng nen qui 32 gid.
Bien dong 1
•51 _
Tbcri eian bao q u i n (giir)
Hinh 5. Sfl bien doi cua TVC va mat so Pseudomonas spp. tren phi le ca rd phi d nhiet dp lanh bien dpng 1 3.4. Bien ddi cua TVC vi mat so Pseudomonas spp.
tren phi le ca ro phi d nhiet dp lanh bien dpng 2 Dfla vio ket qua phan tich vi sinh vat tren do thi hinh 6 cd the thay: thdi ban sfl dung cho phi le ci rd phi dflpc bao quan d che dd nhiet dp md phdng bien d^ng 2 la khdng qua 50 gid. Ket qua nghien cflu niy phan inh sfl sai pham nhiet dp tfl nha miy sin xuat den ndi tieu thu sin pham, lam cho nhiet dp sin pham tang cao, dan den sxi gia tang mat sd vi sinh vat gay hfl hdng sin pham. Ca TVC vi
Pseudomonas spp. deu cd xu hfldng phit trien sau 94 gid bio quan d che dp nhiet dp lanh bien dpng 2.
Mat sd Pseudomonas spp. ban dau 4,42 x 10^ CFU/g tang den 6,76 x 10" CFU/g (d 168 gid). Trong khi dd, TVC vflpt ngfldng quy dinh d 50 gid vdi mat sd li 2,7 X 10' CFU/g. Ket qua nay tfldng ddng vdi nghien cflu cua Tran Thi Thu Le (2015) vi Huynh Thi Ai Vin (2015) khi nghien eflu anh hfldng eiia nhiet dp den sfl phat trien cua nhdm vi sinh vat giy hfl hdng dac trflng tren cdc doi tflpng tdm su va ca Tra
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6. Sfl bien doi
60 SO 100 120 140 160 180 Thtri gian bao quan (gicr)
cua TVC va Pseudomonas spp. tren phi le cd rd phi d nbi?t dp lanh bien d p n g 2 IV. KET LUAN
Cdc ket q u i nghien cflu tren chi ra r i n g nhiet d p v i thdi gian b i o q u i n i n h hfldng Idn d e n sfl phdt trien cua vi sinh v i t . N h i e t dd b i o q u i n cang eao thi sfl p h i t trien c u a vi sinh vat t r e n phi le ca cang dien ra m a n h m e . Dfla v i o ket q u a bien ddi cua T V C va m^t sd Pseudomonas spp. d nhi?t d p lanh t h e o thdi gian b i o q u i n , ed the dfl d o i n Iflpng vi sinh v i t va t h d i b a n sfl d y n g eua phi I& e i rd p h i t h e o lich sfl nhi?t d p t r o n g chuoi c u n g flng lanh, tfl d d gdp p h a n kiem sodt tdt chat Iflpng phi le cd rd phi t r o n g chuoi e u n g flng.
T A I L I £ U THAM KHAO
B0 Y te, 2007. Quyet djnh so 46/2007/QD-BYT ngay 19/12/2007 ve vi?c ban b i n h "Quy dinh gidi ban tdi da d nhiem sinh hpc v i hoa hpc trong thflc pham".
Ha Npi.
H i Kieu, 2016. Nd lUc chung cho muc tieu 300.000 tdn cd rd phi ndm 2020. ngay iru) cap: 01/6/2018. Dia chi:
https://tongcucthuysan.gov.vn.
Tran Thj Thu L?, 2015. Nghien cUu dnh hudng cda nhiet do thdp di'n sU bien doi cua mdt so vi sinh vdt gdy hdng dac trUng vd gdy benh hien dien tren tdm su (Penaeus monodon) nguyen lieu trong qud trinh bdo qudn. Luan van Thac si. TrUdng Dai hpc Nha Trang.
Mai Thi Tuyet Nga, 2016. Nghien cflu ve mat do Coliform va Escherichia coli tren tdm su nguyen lieu khi b i o q u i n d nhiet dp dUong thap. Tap chi Thuy Mifi TrUdng Dai hoc Nha Trang, so 4, trang 91-99.
T C \ ' N 7138:2013. 2013. Thit v i san pham thit - D | n h lupng Pseudomonas spp. gii dinh. Tong cue Tieu chuan Do lUdng chat lUpng tham dinh, Bp Khoa hpc v i Cdng ngh?.
Huynh Thi Ai Van, 2015. Nghien ciiu dnh hUdng cda nhiet do thdp den sU bien doi cua vi sinh vdt gdy hdng dac trUng {Pseudomonas spp.) vd vi sinh vat gay benh (Coliform. E. coli) hien dien tren fillet cd Tra (Pangasius hypophthalmus) bdo qudn lanh. Luan van Thac sT. Khoa Cong nghe ThUc p h a m , TrUdng Dai hpc Nha Trang. Nha Trang.
A h m e d HA. 2005. Nairn UBacterial diversity of Tilapia (Oreochromis niloticus) cultured in brackish water in Saudi Arabia. Aquaculture, V.250, p.566-572.
Chill-on, 2007. Approach of establishing a shelf life model for fish and poultry. Final description.
FAO, 2017. FAO y e a r b o o k Fisheries and aquaculture statistsics 2015. Rome: Food and Agriculture Organization of the United Nations, 78 pages.
Mai Thi Tuyet Nga, H u y n h Thi Ai Van, 2017. Research article: Kinetics of Quality Changes of Pangasius Fillets at Stable and Dynamic Temperatures, Simulating Downstream Cold Chain Conditions.
journal of Food Quality Hindawi, 9 page.
NMKL 86 4^^ ed 2006, 2006. Aerobic microorganisms.
Determination in food at 30-'C 20°C or 6.5-C Nordic Committee on Food Analysis.
V^Sif,2017.Bdnlinthudngmailhuysdnsd3.r,siytray cap 24/3/2018. Dia chi: h t t p . , f l , „ , „ g h e c a v ! e L m org.vn.
VASEP, 2018. Sdn luong ca rd phi tren todn cdu dSn ndm 2030. ngay tniy cap 10/10/2018. Dia chi- h t t o / / hoinghecavietnam.prg.vn
Xing S., Zhang X., Liu W , ' i » n D., Hu I 2017 Modeling growth of specific sp,„la„e organ in tilapia: Comparison Baranvi . i, 6*"^"is
' • i^ni-square ' " ' model.
automatic interaction detectic African journal of Biotechnology.
' ' 1 0 61)17.
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Changes oi Pseudomonas spp. and total viable counts in Nile Tilapia fillets during low temperature storage
Nguyen Thi Kieu Diem. Nguven Thuy Van Duyen, Mai Thi Tu\el Ni;a Abstract
The study aimed to investigate the changes of Pseudomonas spp. count and total viable count (TVC) in Nile tiljpia fiUcK during low temperature storage at 5 stable temperature regimes (1, 4, 9, 15, and 19 ± T C ) and 2 dynamic regimes, simulating the end of supply chain conditions. Results showed that the microbial counts increased with tune and at higher temperatures. TVC in tilapia fillets exceeded the allowable limit of 10'' CFU/g after 144 h at I :- 1 "C (1.1 - 10' CFU/g), 48 h at 4 ± 1 -"C (2.4 x 10" CFU/g), 24 h at 9 ± 1 C (1.47 « 10^ CFU/g), 24 h at 15 ± L'C (I S.* X 10" CFU/g), and 20 h at 19 + 1 "C (1.28 « 10" CFU/g). Meanwhile, the counts of Pseudomonas spp. after 144hat 1± l " C ; 4 8 h a t 4 ± 1 "C; 24 h at 9 ± 1 "C; 24 h at 15 ± 1 "C and 20 h at 19 ± 1 'C were 3,62 - 10^ 2.17 - 10';
4.43 X 10*; 2.68 « 10*; 1,55 x 10^ CFU/g, respectively. At the 2 dynamic temperature regimes, TVC and Pseudomonas spp. counts raised sharply when there was an increase in storage temperature, revealing the negative effect of temperature abuse to the aquatic product quality.
Keywords: Pseudomonas spp., total viable count, tilapia fillet, low temperature storage
Ngay nhdn bai: 10/8/2019 Ngfldi p h a n bien: T S Nguyen Thi Ngoc T i n h Ngay phan bi?n: 22/8/2019 N g i y duyet d i n g : 9/9/2019
