^Mpt so k€t qua nghien cufu thiet bj say mang do hat gac bang phildng phap say thang hoa
SOME RESEARCH RESULTS ON DRYING MEMBRANE OF GAC FRUIT SEED BY SUBLIMATION DRYING METHOD
D6 Minh Chien', PGS,TS. Tran Nhii Khuydn^
'NCS TrUdng Dai hoc Ndng nghiep Ha Ndi. Don vi cdng tdc: TrUdng Cao Dang Cdng nghiep vd Xay diing 'TrUdng Dai hpc Ndng nghiep Hd Ndi
TOM TAT
Ihict bi say thdng hoa STH-50 dUdc thiet kevd die tao tai Bo mdn thiet bi bdo qud vd che bien nong san khoa Cd Dien triidng Dai hoc Ndng nghiep Hd Ndi, dung desdy cdc loai san pham mdn cam vdi nhiet nhii rau qud, thit cd, diidc lieu, enzyme,... Ddy Id he thong thiet bi Idm viec gian doan, cd 2 binh ngUng-ddngbang Idm vice lech pha nhau (binh ndy dang dgiai doan ngUng-ddng hdng hdi nUdc thi binh kia dang dgiai doan xd bang vd ngiidc lai), san pham say diidc Idm lanh ddng cUc nhanh bang N, Idng vd xd bang bang nhiet sinh ra d gidn ndng sau mdy nen hdi mdi chat lanh cua he thong lanh, nhd dd da ndng cao chat lUdng sdn pham, giam
thdi gian say vd chi phi ndng lUdng rieng cho qud trinh say.
Ket qud thUc nghiem ddn yeu td khi say mdng do hat gac da xdc dinh dUdc miic do anh hUdng vd chieu bien thien ciia cdc yeu to: nhiet do lanh ddng T^^ ("C), nhiet do biic xq T^^ ("C) vd chieu ddy Idp vat lieu say S (mm) den hdm lUdng carotenoid C^ (mg/lOOg), hdm lUdng vitamin E V.(mg/100g), thdi gian say t(h) vd chi phi ndngltidng rieng N^ (kWh/kgSPK) vd dd lUa chon dUdc khoang nghien ciiu thich hdp ciia cdc yeu to lam cdsd cho phUdngphdp nghien cUu thUc nghiem da yeu to nhii: nhiet do lanh ddng -30 H- -38f^C, nhiet do biic xq 24 H- 4(fC, chieu ddy Idp vat lieu say 5 -^ 25mm.
Tii khda: Chi phi ndng liidng rieng, he thong thiet bi say thdng hoa.
ABSTRACT
Sublimation dryer STH-50 designed and manufactured at Department of Storage and processing Equipment, Faculty of Engineering, Hanoi University of Agriculture, is used for drying products being sensitive to temperature such as vegetable, fruit, meat, fish, medicinal herb, enzyme, etc. This is a discontinued system with two dephasingfrozen condensers (one condenser is in condense-freezing phase while the other one is in de- icing phase and inverse). Drying product is extra-fast frozen by nitrogen liquid and de-iced by thermal energy from heater behind refrigerant compressor, therefore it can increase product quality, and reduce drying time
and specific energy consumption for drying process.
Results of single-factor experiment when dry red membrane of gac fruit seed determined affection de- gree and varying trend of factors such as freezing temperature T,^ (°C), radiation temperature T^ ("C) and layer
deep of drying product S (mm) to carotenoid content CJmg/lOOg), vitamin E content Ve(mg/100g), drying time t(h), specific energy consumption iV (kWh/kg SPK), and selected appropriate research range for factors as the base for multi-factor experimental research such as freezing temperature -30 H- -38''C, radiation tempera- ture 24 -i- 40°C, thickness of drying product layer 5 ^ 25mm.
Keywords: specific energy consumption. Sublimation drying system.
TAP CHf CO KHI VIET NAM • Sd 12 (Thang 12 nam 2011)
NGHIEN cufu - TRAO D 6 I
1. DAT VAN DE 2. VAT LIEU VA PHLfONG PHAP NGHIEN CUtJ
Gac cd ten khoa hpc Momordica cochin-
chinensis trdng d vung Ddng Nam chau A tfl 2.1. Noi dung nghien ciiu mien Nam Trung Quoc den Ddng Bac Australia,
Viet Nam (chu yeu dUdc trdng d Mien Bac vd tap Nghien cflu thiet ke thiet bi say thang trungdcdc Tinh Hdi Phdng, Hdi DUdng, HdNdi...) hoa
Mdng hat gac Id thdnh phan cd gid tri nhat gdm
cd: protein, lipid, glucide vd rat nhieu vi chat nhfl: Nghien cUu thUc nghiem xdc dinh anh carotenoids, licopene, cac vitamin va khoang chat, hUdng cua mot sd thdng sd den qua trinh say trong dd ham lUpng (3- carotene cao gap 1.8 lan so
vdi dau gan ca thu, gap 15 lan so vdi cu cd rot vd 2.2. Vat lieu nghien ciiu gap 68 lan so vdi cd chua". Vi vay, mdng hat gac
ngodi viec sfl dung 1dm thUc pham md cdn dUpc Vat lieu thi nghiem la gac qua chin dUpc dung 1dm dUpe pham vd my pham rat cd gid tri trdng d Gia Lam Hd Ndi. Mdng dd cua hat cd nhU: vien nang, thudc md, tinh dau, kem dUdng thdnh phan chinh nhfl sau: nfldc 71,42%; pro- da,... [ 1; 4; 5]. tein 2,1%; lipid 7,9%; glucide 10,5%; xo 1,8%;
khoang 0,7; beta caroten 59,84mg/100g; lycopen Do gac qua tUOi thu hoach theo mua vd rat 78,43mg/100g; vitamin E 16,88mg/100g.
de bi hu hdng nen de dU trfl nguon nguyen lieu
ngUdi ta tien hanh tdeh mdng dd hat gac, mang Qua trinh say mdng dd hat gac dflpc tien say khd den dp am an todn de bdo quan. Hien nay, hdnh nhfl sau: Ifla chpn qua gac tfloi, chin dd deu viec say mang dd d nfldc ta dflpc thflc hien theo khdng dap, thdi, mdc, khdng chpn qua chin nbfln, phflong phap say nhiet thUdng d dp cao (50-70''C) sau benh, sau dd rfla sach, de rao nUdc, dung dao trong cdc thiet bi say vi ngang, tham chi trong cac bd ddi lay bat, dUa vdo may cbd de tach het phan Id say thu cdng, sfl dung khdi Id 1dm tac nhan say mdng dd bao quanh hat gac, sau dd dfla vdo may nen chat lUpng san pham say khdng cao, dac biet xay nbuyen de dam bao dp ddng deu ve thdnh la cac hdm lUpng vitamin, caroten, lycopen de phan hda hpc cung nhU mdu sac. Cho nguyen phan huy dudi tac ddng cua nhiet. PhUOng phap lieu bam nbuyen vdo khay, gat phang vd dUa vdo say d nhiet dp thap (0-50°C) trong cac thiet bi: say budng thang hoa. Vat lieu say dUpc 1dm lanh ddng chan khdng, say bom nhiet vd dac biet la phUOng nhanh bang phUOng phap phun NitO Idng vdo cac phdp say thang hoa (say lanh ddng d nhiet dp khay chUa vat lieu say d trong budng thang hoa -20-^-40°C) da khac phuc dUpe hodn todn nhflng cho den khi dat nhiet dp lanh ddng theo yeu cau nhupc diem cua phUOng phap say nhiet nen da thi nghiem, sau dd tien hdnh say khd trong binh gifl gan nhfl nguyen ven chat luong sdn pham tUOi thang hoa cho den khi dp am dat 7% mdi dUa ra ban dau . 1dm ngudi, ddng gdi chan khdng vd bao quan d dieu kien nhiet dp thUdng 2 ngdy sau dd mdi dUa ThUc te d nUdc ta hien nay phUOng phdp ra phan tich [1; 4; 5].
say thang hoa chUa dUpc trien khai vd Ung dung
pho bien do thiet bi nhap ngoai cd gia thdnh rat 2.3. PhiiOng phap nghien ciiu cao, chi phi van hdnh va chi phi nang lUpng khd
Idn. Vi vay, viec nghien cflu thiet ke che tao he Ap dung phUOng phap nghien cflu thUc thdng thiet bi say thang hoa nham tao ra sdn pham nghiem dOn yeu td de nghien cflu anh hUdng say CO chat lUpng cao, giam chi phi cho qua trinh rieng cua cua 03 yeu td: nhiet dp lanh ddng say la van de cap thiet de trien khai flng dung rdng T,^(°C), nhiet dp bflc xa \Ji°C) vd chieu ddy Idp rai trong san xuat Id van de cd y nghia kinh te rat vat lieu say S (mm) den hdm IflOng carotenoid
Idn. Cj(mg/100g), hdm Iflpng vitamin E V (mg/lOOg), ci^
ham lupng vitamin H V (mg/lOOg), thdi gian say
t(h) ^•a chi phi nang lupng rieng N. (kWh/kg SPK). Dp khd ddng deu ciia san pham say dflpc xac djnb theo phUOng sai do dac dp am cua cac Cac thdng so nghien cuu diipc xac dinh mau san pham say d cac vi tri khac nhau trong nhu sau: Inidng say.
Ihdi gian sa\- la khoang thdi gian thUc Hdm lU(?ng carotenoid tong sd vd ham hien nioi nic duoc tinh tu I hdi diem khi bat dau lUpng vitamin E dUpc xac djnh theo phUOng phap say cho den khi san pham say dat do am 7",. va HPLC nhd may do sac ky Idng hi^u nang cao, ma dupe xac dinh bdng ddng ho do ihdi gian. hieu RID-lOA vd SPD-HIOAVP (Nhat Ban).
Nhiet dp v.i dp am mdi trUdng trong 3. KET QUA VA THAO LUAN khdng gian budng say xac dinh bdng thiet hi do
dien t\"i hien sd ma hieu 1^-OX-301 A (Han (.)iide) 3.1. Thi^t kef thi^t bi say Dp am cua san pham say dUpc xac dinh
bang may do Data Holp MC-78()5 (Trung Quoc), sai so ± 0,1 "o. Day la loai thiet bi do hien dai, cd dau cam bien nhiet dp va dp am dUpc cam sau vao trong klidi \'at lieu can do vd nhiet dp vd dp am cua vat lieu trong budng say dUpc hien thi sd tren man hinh cua thiet bi do dat d ngodi budng say.
H? thdng thiet bi say thang hoa STH-50 dupe thiet ke vd che tao tai Bd mdn Thiet bi bao quan vd che bien ndng sdn khoa Co Dien trfldng Dai hpc Ndng nghiep Hd Ndi. So do nguyen ly cau tao cua be thdng thiet bi say dflpc the hien tren hinh 1[2;3].
Hinh 1: Sd do cau tao thiet bi say thdng hoa STH - 50
1. Binh thdng hoa; 2. Van dieu chinh dp sudt; 3,4. Binh ngiing dong hdng; 5. Tu dieu khien; 6. Gidn Idm mat moi chat lanh; 7. Mdy nen moi chat lanh; 8. Bdm chan khong; 9. Gidn dat khay say; 10. Tam gia nhiet; 11. Khay say;
12. Bo phan phun N long.
m TAP CHI CO KHI VIET NAM V Sd 12 (Thang 12 nam 2011)
NGHIEN cufu - TRAO D 6 I
He thdng thiet bi say thang hoa gdm cd cac bd phan chinh nhU sau: Binh thang hoa 1 cd dang hinh tru, ben trong cd lap cac gidn khay chfla vat lieu say 10 xen ke vdi tam gia nhiet 11. Bom chan khdng 8 cd nhiem vu hut hoi nfldc thoat ra tfl vat lieu say de tao ra dp suat chan khdng can thiet cho qua trinh thang hoa am. Binh ngflng ddng bang 3 vd 4 ket hpp vdi he thdng lanh 6 vd 7 cd nhiem vu 1dm ngflng tu vd ddng bang hoi nfldc do bOm hut ra de giam tai cho bom chan khdng vd tranh ngflng tu nUdc trong bOm chan khdng. Bd phan cap nhiet gdm cd cdc tam gia nhiet 10 dUpc lap xen ke vdi cac khay chfla vat lieu say cd nhiem vu cung cap nhiet cho qua trinh say. Bd phan phun NitO Idng 12 gdm bom vd cdc vdi phun cd nhiem vu phun Ni to Idng de 1dm lanh ddng nhanh vat lieu am trflde khi say.
Sfl dung hai binh ngflng 1dm viec lech pha nhau (binh ngflng nay dang d thdi ky ddng bang thi binh ngflng kia dang d thdi ky xa bang vd ngUpe lai), khdng mat thdi gian dflng may de xa bang.
Sfl dung bpi NH^ sau may nen cua he thdng lam lanh de pha bang trong binh ngflng ddng bang nen da rut ngan dUpe thdi gian pha bang vd tiet kiem nhiet nang.
Thiet bi cd cau tao dPn gian, vdn dau tU thiet bi, cd Idia nang say dUpc nhieu loai vat lieu khac nhau, ke ca vat lieu d trang thai ran vd Idng.
Nhupc diem : Ky thuat van banh may kha phUc tap, ddi hdi cdng nhan phai cd tinh than trach nhiem vd trinh dp tay nghe cao.
Vdi ket cau nhU tren he thdng thiet bi say 3.2. Khao sat anh hfldng cua mot so yeu to den thang hoa STH-1 cd Uu diem ndi bat nhU sau: chat liiOng san pham say
Ap dung phuong phap lanh ddng cUc nhanh bang each phun NitO Idng vdo vat lieu say nen cd Uu diem hon so vdi cac phUOng phap lanh ddng khac Id tao ra sdn pham lanh ddng cd chat lupng cao (hinh thdnh nhieu tinh the da cd kich thudc nhd), thdi gian lanh ddng ngan (2-3 phut), chi phi cho qua trinh lanh ddng thap vi NitO Id pham phu trong san xuat oxy Idng, gia thdnh re
Da tien banh thi nghiem say mdng dd hat gac trong thiet bi say thang hoa STH-50. Trong tat ca cac thi nghiem deu bd tri sd lan lap lai Id 3, mflc bien thien la 5. Ket qua thi nghiem da xac dinh dflpc mflc dp anh hfldng cua cdc yeu td nhfl sau:
a. Anh hiXdng nhiet do lanh ddng vat lieu say T^^
CO
- Thdi gian say giam tfl 2,5-3 lan vd dac Dieu kien thi nghiem: Nhiet dp ngudn biet Id khdng mat nhieu thdi gian de lanh ddng bflc xa T^^^ = 32°C, chieu day Idp vat lieu say S = san pham say. 15mm. Ket qua thi nghiem dflpc bieu dien tren do
thi hinh 2.
C t ( m g / 1 0 0 g )
420
4 0 0 -
380 •
360
340 •
• 3 4 -
• 3 2 -
• 30
2 8 '
2 6 '
. 2 4 . Ve
•1 mg/lOOg)
V
^
y,
<y
^
? ^
? - ^
^
t - — • ' t(h)
\
• 15 •
. 14 .
• 1 3 •
• 12 •
. 11 .
10 • Nr(k 3.2
3.0
2.6
•2.2
Nr (kWh/kg SPK)
-30 -32 -34 -36 -38 - T ; (C)
- • — C l (mg/lOOg) — « — Ve (mg/lOOg)—*=— t (h) — • — N r (kWh/kg SPK)
Hinh 2: Do thi hieu diin anh hUdng cua nhiet do lanh dong vat lieu say T,^ (°C )
Tren do thi binh 2 ta thay, khi giam nhiet dp lanh ddng (lanh sau) thi tdc dp thang boa am se xay ra manh liet hOn do sfl chenh lech nhiet dp Idn tao nen ddng Iflc thoat am cao, hon nfla do lanh ddng nhanh va sau bang phUPng phap phun NitO Idng nen nfldc tfl do trong vat lieu say khi ket ddng tao ra nhieu linh the da min cdng thuan Ipi cho qua trinh thang hoa am nen thdi gian say giam. Do thdi gian say giam nen chi phi nang lUpng rieng giam, ham lUpng carotenoid vd vitamin E vi the cung tang len, dac biet do hinh
thdnh nhieu tinh the da min, sau khi nfldc thang hoa de lai cdc Id xdp cd kich thUdc nhd n^n it gay bien ddi cau true sam pham say.
/;. Anh hudng cua nhiit dd ngudn biic xq T^^ (°C) Di^'u ki?n thi nghiem: Nhi?t dp lainh ddng T|^ = 34'C chieu ddy Idp vat li^u say S = 15mm.
Ket qua thi nghiem dflg(c bi^u dien tren do thi hinh 3.
- • — ( I i m g 1(111(11 V c d i i g H J I i t i i — A — K i l l - - N I ( k \ \ l l k i ; S P K I
Hinh 3: Dd thi anh hUdng ciia nhiet do ngudn bUc xq T^^ (°C)
dung cua nhiet, dac biet Id nhiet dp cao. Rieng doi vdi hdm Iflong carotenoids bi giam thap d nhiet dp (24"C) do thdi gian thdi gian say keo dai va dat gid tri cao nhat flng vdi nhiet dp tam gia nhiet bflc xa 28''C.
Tren do thi hinh 3 cho thay, khi tang nhiet dp tam gia bflc xa se se tang ddng Iflc cua qua trinh thoat am trong vat lieu say do dd thdi gian say giam nhanh, chi phi nang IflOng rieng vi the gidm xudng nhflng giam cham hon flng vdi nhiet dp tam gia nhiet bflc xa 32-40"C (do phai tang cdng suat cua ngudn nhiet), dac biet khi nhiet dp Idn hon 40°C (43-45''C) thi say ra hien tflpng tan bang sdm (phd vd thang hoa). Ddng thdi khi tang nhiet dp tam gia nhiet bflc xa thi hdm IflOng ca- rotenoids, bdm IflOng vitamin E deu giam xudng vi day Id nhflng thdnh phan de bi bien ddi dfldi tdc
c. Anh hudng cua chieu ddy Idp vat lieu S (mm) Dieu kien thi nghiem: Nhiet dp lanh ddng T,^ = - 34"C, nhiet dp ngudn bflc xa T^,^ = 32°C. Ket qua thi nghiem the hien tren do thi hinh 4.
C U m g / I O O g l
340
320 34 •
• 32
• 3 0 •
• 28
• 2 6 -
. 24 Vc
1 Ml,; lOOg)
r ^
}
^ ^
"H
/^ N
>
^ /
K
Kill
i 15 •
14
• 13
• 12 -
• 1 1
Nrl
.>._
• 2 8
• 2.6
• 2.4
NrlkWhkgSPKl
5 10 15 20 25 s(mm)
— • — C l (mg/lOOg) — « — Ve (mg/lOOg) * I (h) — • — N r (kWWkg SPK)
Hinh 4: Do thi dnh hUdng cua chieu ddy Idp vat lieu say S (mm) m TAP CHI CO KHI VIET NAM V Sd 12 (Thang 12 nam 2011)
NGHIEN cufu - TRAO D(!)l
Tren do thi hinh 4 ta thay, khi tang chieu ddy Idp vat lieu say thi thdi gian say tang len do hoi am thoat ra phai khac phuc trd Iflc khi di qua chieu ddy Idp khd, vi vay chi phi nang Iflpng rieng tang, ddng thdi hdm IflOng carotenoids vd vitamin giam xudng.
Ket qua phan tich hda hpc vd phan tich cam quan cho thay, san pham sau klii say thang hoa gifl dupe gan nhU nguyen gia tri dinh dUdng, mdu sac vd mui vi so vdi san pham mdng gac tUOi ban dau. Tren binh 5 Id hinh anh san pham mang dd hat gac sau khi say thang hoa.
^
Hinh 5: Sdn pham mdng do hat gac sau khi say thdng hoa
4. KET LUAN
He thdng thiet bi say thang hoa STH-50 dupe thiet ke va che tao tai Bd mdn thiet bi bdo qua vd che bien ndng san khoa Co Dien trUdng Dai hpc Ndng nghiep Ha Ndi. Day la he thdng thiet bi lam viec gian doan, cd 2 binh ngUng-ddng bang 1dm viec lech pha nhau, san pham say dUpc lam lanh ddng cUc nhanh bang N^ Idng vd xd bang bang nhiet sinh ra d gian ndng sau may nen hoi mdi chat lanh cua he thdng lanh, nhd dd da nang cao chat lUpng san pham, giam thdi gian say va chi phi nang lUpng cho qua trinh say.
Ket qua thflc nghiem don yeu td da xac dinh dupe anh hUdng cua cac yeu td: nhiet dp lanh ddng T,^(^^C), nhiet dp bflc xa Tj^^(^C) va chieu day Idp vat lieu say S (mm) den ham Iflpng carotenoid Cj(mg/100g), ham Iflpng vitamin E V(mg/100g), thdi gian say t(h) va chi phi nang Iflpng rieng N^
(kWh/kg SPK) va da Ifla chpn dflpc khoang nghien cflu thich hpp cua cac yeu td lam cP sd cho phflOng phap nghien cflu thflc nghiem da yeu td nhfl: nhiet dp lanh ddng -30 ^ -38°C, nhiet dp bflc xa 24 ^ 40°C, chieu ddy Idp vat lieu say 5 ^ 25mm. •
Tai lieu tham khao:
[1] Bui Minh Dflc vd cdng sfl (2004), "Bdt Gac va dau Gac. Ham lUOng cao P - caroten, lycopen vd a tocopherol dam bao dinh dUdng ben vflng, phdng vd dieu tri HIV/AIDS", Tap chi cay thudc quy, (17), tr20.
[2] Tran Nhfl Khuyen vd cdc cdng sfl (2008), Nghien cflu quy trinh cdng nghe vd he thdng thiet bi 1dm khd ndng san thflc pham bang phflOng phap say thang hoa, Bao cao tong ket de tdi NCKH cap Bd - trfldng Dai hpc Ndng nghiep Ha Ndi.
[3] Nguyen Van May (2007), Ky thuat say ndng sdn thflc pham, NXB Khoa hpc vd Ky thuat, Hd Ndi.
[4] Nguyin Cdng Suat (2002), "Dau gac - Thflc pham an todn, than dflpc tri nhieu benh va lam dep da". Tap chi Tri thflc tre, (6), tr 34-35.
[5] Nguyin Minh Thuy (2010), Da dang hda cdc san pham che bien tfl gac, Hdi thao Quoc te vdi chu de Tinh da tdc dung ciia gac to chUc tai Hd Ndi.