07/06/2011 IPN-Dept ITP/IPB
Trend of Alternative Food P Processing i T Technologies h l i (based on IFT’s Report)
Purwiyatno Hariyadi ITP530 Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
1
07/06/2011 IPN-Dept ITP/IPB
Purwiyatno Hariyadi/ITP530
Alternative Food Processing Technologies : Microwave and Radio Frequency Ohmic and Inductive Heating High Pressure Processing P l d El Pulsed Electric t i Fi Field ld High Voltage Arc Discharge Pulsed Light Oscillating Magnetic Fields Ultraviolet Light Ultrasound X-Rays
• • • • • • • • • •
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
2
07/06/2011 IPN-Dept ITP/IPB
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
3
07/06/2011 IPN-Dept ITP/IPB
Purwiyatno Hariyadi/ITP530
PENGGUNAAN GEL MIKRO (MICROWAVE/MW) UNTUK KEPERLUAN INDUSTRI : Gelombang mikro Berpeluang Penggunaan MW Berdekatan dan perlu diatur mengganggu Tumpang tindih oleh badan proses Dengan kisaran yang berwenang, komunikasi Gelombang radio Mis. Di AS : Federal Communication Commission memperbolehkan pemakaian 4 frekuensi MW : 22150, 5800, 2450 dan 915 MHz Paling banyak : 915 dan 2450 MHz Inggris : 915 dan 2450 MHz Jerman : 27,12; 433,92 dan 2450 MHz Eropa Timur: 2375 MHz Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
4
07/06/2011 IPN-Dept ITP/IPB
PEMANASAN DIELEKTRIK (& GEL MIKRO) dipantulkan oleh metal diserap (diubah menjadi panas) oleh dielektrik : internal heating (Molecular friction).
δ OδH δ+ δ+ H
+/Generator (Oscilator)
Bahan pangan
Hδ+ H
δ+
“Perub. Orientasi polarisasi”
Oδ-
+/-
+ +
Ionic displacement
Purwiyatno Hariyadi/ITP530
Listrik
Konversi Energi
Panas
P = 2π(ε ( o)( ε’)) tan δE2f P = 5.56x10-13 (ε’) tan δE2f P = jumlah panas yang diproduksi per satuan volume [=] W/m3 εo= permitivity of free space ε’ = konstanta dielektrik (sifat fisik bahan yang berhubungan dengan polaritas atau Σ dipole) δ = loss angle E = kekuatan medan listrik [=] volts/m f = frekuensi (hz, s-1) ε’ tan δ = ε’’ = loss factor
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
5
07/06/2011 IPN-Dept ITP/IPB
LOSS FACTOR ∈ε” = f (SUHU, FREKUENSI) Mashed Potatoes
35 140
Cooked carrots
25
120
20
100
15
80 60
10 H2O
5 0
450 MHz
160
30
-20
0
20 SUHU
40
60
40
900 MHz
20
2700 MHz MH
0 -20
(oC)
20
40 SUHU
60
(oC)
Purwiyatno Hariyadi/ITP530
DAYA PENETRASI GEL MIKRO = d
d=
λo 2π ε' tanδ
λo = panjang gelombang
Kedalaman penetrasi, d[=] cm Kadar air
ε’
915 MHz
2450 MHz
tinggi sedang rendah
15 4 1,5
8,4 11,7 22,1
3,1 4,4 8,2
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
6
07/06/2011 IPN-Dept ITP/IPB
PENINGKATAN SUHU DALAM PRODUK Jumlah panas yang diperlukan untuk meningkatkan suhu produk sebesar ΔT Q = mc ΔT Q = ρVcΔT atau ΔT= Q/ρVc dimana V = volume Jumlah panas yang diproduksi oleh pemanasan gel mikro : Q = PVΔt Q = (5.56 x 10-13 ε” E2 f)VΔt Jadi, ε” E2 f Δt ΔT = 5.56 x 10-13 ρc c untuk pemanasan gel mikro yang sama, ΔT = ≈
ε”
= f (Komponen bahan pangan) ρc homogenitas pemanasan = homogenitas bahan pangan Purwiyatno Hariyadi/ITP530
Konfigurasi sistem sterilisasi/pasteurisasi dgn pemanasan dielektrik dan gelombang mikro MW Generator Waveguide
Treatment Chamber
Conveyor belt
MW generator (magnetron) : merubah energi listrik menjadi gel. Mikro Waveguide : memfocuskan pancaran m.w (terowongan dari tabung Al) Treatment chamber: ruang tertutup/terlindung oleh logam Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
7
07/06/2011 IPN-Dept ITP/IPB
KARAKTERISTIK PEMANASAN GEL MIKRO • • • •
Memanaskan daerah yang mengandung air Pemanasan berlangsung cepat Tidak menyebabkan “gosong”pada permukaan Mudah/Praktis
APLIKASI SPESIFIK PEMANASAN GEL. MIKRO : • Cocok untuk mengeringkan bahan setengah kering Contoh : Pasta - waktu pengeringan turun dari 8 jam menjadi 90 menit - jumlah bakteri 15 kali lebih kecil - tidak mengalami case hardening Biji-bijian : terutama untuk Benih - meningkatkan laju germinasi
Mengeringkan bagian dalam (tanpa overcooked dipermukaan) Purwiyatno Hariyadi/ITP530
APLIKASI PEMANASAN GEL. MIKRO (UMUM): •Rumah tangga : microwave oven •Komersial 4Pemanasan tanpa merubah sifat-sifat dasar produk : th i & defrosing thawing d f i (tempering) (t i )
4Pemanasan dengan merubah sifat-sifat dasar produk : Pengembangan adonan & pemanggangan Pemblansiran buah/sayuran : inativasi enzim Pemasakan (cooking) Roasting (untuk kacang-kacangan)
4Pengeringan : Dehidrasi pada tekanan normal Dehidrasi pada tekanan vakum
4Inaktivasi Mikroba :
Sterilisasi & Pasteurisasi (kurang sukses ! : masih dalam penelitian!) Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
8
07/06/2011 IPN-Dept ITP/IPB
APLIKASI PEMANASAN GEL. MIKRO PADA PROSES PEMANGGANGAN Utama : ~ membantu proses pengeringan lanjut Proses pemanggangan dimulai dengan oven tradisional (mengg. udara panas) : Efektif untuk produk dengan kadar air tinggi Dengan semakin menurunnya kadar air : efektifitas oven menurun case hardening?! Pengeringan/pemanggangan selanjutnya : oven gel. Mikro mengeringkan bag dalam (tanpa “overcooked” di permukaan) Purwiyatno Hariyadi/ITP530
APLIKASI PEMANASAN GEL. MIKRO PADA PROSES THAWING : ☺ Konduktivitas panas air < konduktivitas panas es Proses pencairan : menurunkan proses pindah panas ☺ Loss factor air > loss factor es Proses pencairan : menaikan kadar air dan loss factor >>mempercepat p p proses p pemanasan p ☺ Problem : Pada bahan baku yang ukuran besar - proses pencairan tidak seragam - mengakibatkan overcooked pada bagian ttt
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
9
07/06/2011 IPN-Dept ITP/IPB
APLIKASI PEMANASAN GEL. MIKRO PADA PROSES DEFROSTING : Menaikan suhu produk beku: -20oC menjadi -3oC Untuk daging dan mentega mempermudah penanganan (slicing) Minimum overcooked Cepat : ....................> daging dapat didefrost selama 10 menit (tradisional: beberapa hari pada cold room) Minimum perubahan phase Minimum drip loss (kehilangan karena penetesan) Mutu meningkat: lebih higienik, lebih cepat, dapat dilakukan di dalam box (pengemas) Ruang yang diperlukan sedikit Ekonomis Purwiyatno Hariyadi/ITP530
APLIKASI PEMANASAN GEL. MIKRO PADA PROSES DEHIDRASI :
VS. PEMANASAN TRADISIONAL/UDARA PANAS : Pindah panas turun : thermal conductivity turun pada bahan pangan kering Semakin lama waktu pengeringan mutu sensori dan mutu gizi turun Oksidasi tinggi : mengakibatkan warna dan vitamin menurun. Untuk produk dengan kadar pufa tinggi, terjadi ketengikan Case hardening : perubahan karakteristik permukaan >> keras, susah ditembus oleh panas/uap air (kualitas produk menurun)
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
10
07/06/2011 IPN-Dept ITP/IPB
APLIKASI PEMANASAN GEL. MIKRO PADA PROSES DEHIDRASI :
VS. PEMANASAN GELOMBANG MIKRO : Memanaskan bahan dari dalam : Tidak ada masalah ttg konduktivitas panas Tidak memanaskan udara : mrengurangi ksidasi rendah Tidak terjadi case hardening (pindah massa/uap air .........> lancar) Umumnya dipakai untuk mengeringkan semi/partly dried foods, foods dimana gel. Mikro akan tetap memanaskan daerah yang masih basah, tanpa mempengaruhi daerah/bagian yang sudah kering. Mahal Purwiyatno Hariyadi/ITP530
APLIKASI PEMANASAN GEL. MIKRO : LAIN-LAIN Masih dalam taraf penelitian: Blansir, Pasteurisasi, Sterilisasi
PENGARUH GELOMBANG MIKRO TERHADAP BAHAN PANGAN : tidak ada pengaruh langsung pada mikroorganisme waktu proses menurun retensi gizi lebih baik (prinsip HTST)
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
11
07/06/2011 IPN-Dept ITP/IPB
PEMANASAN OHMIC
elektroda BAHAN
S P = I2 R P=
I2ke-1
I = keEL-1
Power Supply
P : laju jumlah panas yang diproduksi per satuan volume (W.m-3) E : kekuatan medan listrik (Volt cm-1) ke : konduktivitas listrik (ohm-1/m, S/m) I : densitas arus listrik (amps/m2) R : tahanan listrik (ohm-1)
- kecepatan pemanasan tergantung pada nilai ke bahan pangan - ke bahan pangan =f(kadar air, garam ionik dan asam) - ke bahan pangan cair >> ke bahan padat - minyak dan lemak mempunyai nilai ke sangat rendah Purwiyatno Hariyadi/ITP530
PERBANDINGAN ANTARA PEMANASAN GEL MIKRO DAN OHMIC Kriteria
Konduktivitas listrik (siemen/m) Generasi Panas untuk medan listrik 20 V/m (W/cm3) Kenaikan suhu (oC/sec)
Pemanasan Gel Mikro 0.25 0.25--4
1-16 0.25 0.25--4*
Pemanasan Ohmic 0.005--1.2 0.005
0.02 0.02--5 0.004 0.004--1.2*
* kenaikan suhu di permukaan kaleng pada proses pemanasan retort adalah sekitar 0.2oC/sec
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
12
07/06/2011 IPN-Dept ITP/IPB
Arah perambatan panas, Q
Q(r) =
Pr 2
T − T0 = r
Pr 2 P 4k
2 ⎡ ⎛ r ⎞ ⎤ − ⎢1 ⎜ ⎟ ⎥ ⎝ R ⎠ ⎥⎦ ⎢⎣
k = konduktivitas panas Kenaikan suhu maksimum
Tmax − To =
PR 2 4k
Kenaikan suhu ratarata-rata
T − T0 =
PR 2 8k Purwiyatno Hariyadi/ITP530
Contoh : Sebuah bahan berbentuk silinder dengan diameter 2R dan panjang L. Berapa Δ voltase (E) yang perlu diberikan supaya terjadi peningkatan suhu di pusat bahan sebesar (Tmax-T0)oC, dimana suhu awal = T0. J Jawab b: Gunakan persamaan peningkatan suhu
PR 2 4k I2R 2 kE − T0 = , I= e 4k ek L
Tmax − T0 = Tmax
2
⎛ k eE ⎞ 2 ⎟ R ⎜ ⎛ E2R 2 L ⎠ ⎝ = ⎜⎜ Tmax − T0 = 2 4k ek ⎝ 4L Jadi, ⎛L ⎞ k E = 2⎜ ⎟ ⎝ R ⎠ k e T0
⎞⎛ k e ⎞ ⎟⎟⎜ ⎟ ⎠⎝ k ⎠
T0 (Tmax − T0 ) Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
13
07/06/2011 IPN-Dept ITP/IPB
Vs PEMANASAN OHMIC & GELOMBANG MIKRO Mirip dengan pemanasan gel. Mikro : Konversi enegi listrik menjadi energi panas Penetrasi panas/daya penetrasi : tidak terbatas Suhu dalam bahan pangan merata (∇ (∇T ≈ 0) Tidak perlu “pengadukan” Cocok untuk memanaskan bahan pangan cair dgn partikulat : sop dll.
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
14
07/06/2011 IPN-Dept ITP/IPB
Nilai konduktivitas listrik beberapa bahan Bahan
nilai ke (s/m)
Air murni (25oC) Asam sulfat (25oC)
5,7x10-6 1
kentang(19oC) wortel (19oC) kacang kapri (19oC) daging sapi (19oC) Larutan pati (5 (5,5%, 5% 19oC) + garam 0.2% + garam 0,55% + garam 2%
0.037 0,041 0.17 0,42 0,34 1,3 4,3
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
15
07/06/2011 IPN-Dept ITP/IPB
KONFIGURASI SISTEM PEMANAS OHMIC
Elektroda 4
Elektroda 3
Elektroda 1
Elektroda 2
Elektroda 2
Elektroda 1
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
16
07/06/2011 IPN-Dept ITP/IPB
Purwiyatno Hariyadi/ITP530
(ULTRA) HIGH PRESSURE PROCESSING ~ HIGH HYDROSTATIC PRESSURE Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
17
07/06/2011 IPN-Dept ITP/IPB
Historical Timeline 1895 H. Royer uses high pressure to kill bacteria. 1899 Bert H. Hite at the West Virginia Agricultural Experimental Station examined pressure effects on milk, meat, t fruits f it and d vegetables. t bl 1914 P. W. Bridgman coagulated egg albumen under high pressure. 1990 First commercial products like fruit juices, jams, fruit toppings and tenderized meats introduced in Japan. 1995 Orange juice commercialized in France. 1997 Market introduction of guacamole in the US and sliced cooked ham in Spain. 1999 Oysters introduced in the US. 2000 Range of salsas launched in the US market. Purwiyatno Hariyadi/ITP530
High hydrostatic pressure • Foods "pasteurized" pasteurized by HHP undergo pressures of up to 80,000 psi at or near ambient temperatures (under 45°C). • Under these conditions, HHP is effective in inactivating most vegetative pathogens commonly found in the foods. • Commercially available HHP-processed products in E Europe and dA Asia i iinclude l d jjuices, i jjams, jjellies, lli meatt and yogurts. • Consumers in this country can buy HPP-processed guacamole and oysters. Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
18
07/06/2011 IPN-Dept ITP/IPB
High hydrostatic pressure • There is significant commercial interest in development of other products. • Food processed by HHP reportedly has better retention of flavor, texture, color, and nutrients. • The processing cost is slightly higher (two to three cents per pound) than for conventional processes processes.
Purwiyatno Hariyadi/ITP530
How High ?? Two elephants balanced on a piston with a cross section of a dime will create a pressure of 400 Mega Pascal (Mpa). This is approximately 60,000 pounds per square inch.
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
19
07/06/2011 IPN-Dept ITP/IPB
HHP processing
• High Pressure can kill microorganisms by interrupting with their cellular function without the use of heat that can damage the taste, texture, and nutritional value of the food. Purwiyatno Hariyadi/ITP530
HHP processing
• The "mechanism" of high-pressure based bacteria kill is low energy and dd does nott promote t the th fformation ti off new chemical h i l compounds, "radiolytic" by-products, or free-radicals. • Vitamins, texture and flavor are basically unchanged. • For example, enzymes can remain active in high pressure produced orange juice. Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
20
07/06/2011 IPN-Dept ITP/IPB
HHP system • This 35-liter high-pressure b t h unitit ffrom Fl batch Flow International can process up to 700 lbs. an hour and is designed for prepackaged products such as bottled juices. • Units with capacities p up p to 300 liters are available. • Food scientists are optimistic about hydrostatic pressure's ability to extend shelf life and produce safe food. Purwiyatno Hariyadi/ITP530
HHP system
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
21
07/06/2011 IPN-Dept ITP/IPB
Industrial High Pressure Food Processors Complete systems are offered for bulk and in container processes.
Purwiyatno Hariyadi/ITP530
Applications for High Pressure Processing are found in the areas of...
P Preservation ti Elimination or substantial reduction of spoilage microorganisms and enzymes for shelf life extension of refrigerated food products with superior sensory quality, e.g. juices, jams, guacamole, salsa, meat & dairy products, seafood (commercialized) Acidified and low-acid shelf-stable products (under development)
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
22
07/06/2011 IPN-Dept ITP/IPB
Applications for High Pressure Processing are found in the areas of... Food safety Elimination of pathogens: e.g. Listeria in meat products, Salmonella in eggs and poultry, Vibrio in oysters Hypotheses for vegetative cell inactivation... - denaturation of proteins and enzymes - damage of DNA replication & transcription - solidification of membrane (phospho)lipids - breakage of bio-membranes (cell leakage) Spores are very resistant to pressure, but can be destroyed by combining pressure with elevated temperatures Purwiyatno Hariyadi/ITP530
Applications for High Pressure Processing are found in the areas of...
Fruit Juice treated with HHP • Juice tests have shown that food pathogens such as salmonella and E.coli 0157:H7 can be effectively destroyed without changing the fruit juice's fresh, natural characteristics. • A pressure exposure of 80,000 psi for 30 seconds can achieve a 3-5 log reduction of all of the pathogens of concern in fresh juice
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
23
07/06/2011 IPN-Dept ITP/IPB
Applications for High Pressure Processing are found in the areas of...
Oyster treated by HHP • Another example p of food safety y is the destruction of Vibrio bacteria in raw oysters without destroying the raw feel and taste of the oyster. • A pressure of 200 to 300 MPa for 5 to 15 minutes at 25C inactivated : · Vibrio parahaemolyticus ATCC 17803, · Vibrio vulnificus ATCC 27562, · Vibrio choleare ATCC 14035, · Vibrio choleare non-O:1 ATCC 14547, · Vibrio hollisae ATCC 33564 · Vibrio mimicus ATCC 33653 (from: "D. Berlin, D. Herson, D. Hicks, and D. Hoover; Applied and Environmental Microbiology, June 1999“)
Purwiyatno Hariyadi/ITP530
Applications for High Pressure Processing are found in the areas of...
Oyster treated by HHP Pressure shucked raw clams. Pressure not only destroys the vibrio family of bacteria that can be found in shellfish, but also detaches the meat from the shell, saving labor gp production and increasing efficiency.
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
24
07/06/2011 IPN-Dept ITP/IPB
Applications for High Pressure Processing are found in the areas of...
Styrofoam cup subjected to 40,000 psi, fruit pack (with juice) and sliced ham subjected to 80,000 psi.
Purwiyatno Hariyadi/ITP530
Commercial High-Pressure Processed products marketed in Japan, Europe and the United States
Guacamole & Salsas Avomex (Keller, TX)
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
25
07/06/2011 IPN-Dept ITP/IPB
Commercial High-Pressure Processed products marketed in Japan, Europe and the United States
Purwiyatno Hariyadi/ITP530
Commercial High-Pressure Processed products marketed in Japan, Europe and the United States
Jams & Fruit Toppings (Japan) Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
26
07/06/2011 IPN-Dept ITP/IPB
Examples of products commercialised in Europe and treated on HYPERBAR installations supplied by ACB ULTI / PAMPRYL (Groupe PERNOD-RICARD) - France freshey squeezed fruit juice Fresh pressed
ESPUNA - Spain – sliced cooked ham
Purwiyatno Hariyadi/ITP530
Applications for High Pressure Processing are found in the areas of... Texturization As an alternative to heat processing texturization can be accomplished by exposing protein (e.g. egg, whey, soy) and hydrocolloid (e.g. pectin, starch) solutions to hydrostatic pressure. The resulting gels are characterized by uniquely different textures.
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
27
07/06/2011 IPN-Dept ITP/IPB
Applications for High Pressure Processing are found in the areas of...
H t Heat-sensitive iti compounds d HPP offers the unique potential to stabilize products with heat-sensitive components (e.g. flavors, nutrients, biologically active compounds). Biotechnology Specific enzymes can be activated under pressure leading to enhanced reaction rates and shorter process times.
Purwiyatno Hariyadi/ITP530
Thermally-assisted high-pressure lifts quality of shelf-stable foods Process Variables for Optimum Quality Pressure
Products
90°C
700 MPa
Main meal entrees, meats, pasta dishes, most vegetables, sauces, cheese, soups, stews, flavored milk drinks
80°C
830 MPa
Whole potatoes, most vegetables
70°C
1,000 MPa
All potato products, all vegetables, seafood
60°C
1,240 MPa
Eggs, milk
Temperat ture
Source: Richard S. Meyer, PhD, Washington Farms, Inc.
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
28
07/06/2011 IPN-Dept ITP/IPB
Effect of pressure is very similar to the effect of temperature in thermal processes
Figure. Change in inactivation of Zygosaccharomyces bailii with pressure. Note that 345 MPa = 50,000 psi. (Enrique Palou, GRA, BSysE Dept., WSU) Purwiyatno Hariyadi/ITP530
Thermally-assisted high-pressure lifts quality of shelf-stable foods What's needed to commercialize UHP for sterilizing shelf-stable products? Two things must be done. First, develop the kinetic information necessary to file a petition with the FDA and USDA. To do that, we have to select the most heat and pressure-resistant strain of Clostridium botulinum. That work is underway with the Dual Use Science & Technology (DUST) Program 2000 headed by Dr. Patrick Dunne at the U. S. Army Natick Soldier Center in Natick, Mass. Dual use refers to developing the technology for both military and industrial applications. Second, we need commercial-size, inexpensive high-pressure vessels. Flow International Corp. (Kent, Wash.) is nearest to delivering that right now. They have a 215-liter vessel which is very close to all the critical parameters for delivering a sterile product. They're leading with the technology, and just need to build a vessel to order. Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
29
07/06/2011 IPN-Dept ITP/IPB
Dosis Irradiasi •
Dikendalikan oleh “the International Commission on Radiological Units” Rad
•
1 Rad = jumlah irradiasi yang menyebabkan 1 g bahan yang diirradiasi akan menyerap energi sebesar 100 erg (1 Rad = 100 erg/g)
•
Satuan umum
•
1 Grey = jumlah irradiasi yang menyebabkan 1 kg bahan yang diirradiasi akan menyerap energi sebesar 1 joule;
•
1,000 , Grey y = 1 kGy. y
•
100 Rad = 1 Gy
“Grey“
Purwiyatno Hariyadi/ITP530
Dosis Irradiasi
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
30
07/06/2011 IPN-Dept ITP/IPB
PENGARUH IRRADIASI PADA MIKROBA
D10,veg bacterium D10,yeast
D10 : dosis irradiasi yang menyebabkan pengurangan jumlah mikroba dengan faktor 10 D10 dose
Purwiyatno Hariyadi/ITP530
PENGARUH IRRADIASI PADA MIKROBA Organism Dvalue Resistance
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
31
07/06/2011 IPN-Dept ITP/IPB
PENGARUH IRRADIASI PADA MIKROBA _______________________________________________________ organisme medium in D10 (Rad) which irradiated _______________________________________________________ Bacterial spore C botulinum A36 buffer 0.33 106 B53 buffer 0.33 106 B57 canned chicken 0.37 106 C. sprogenes 367 water 0.22 106 Veg bacteria Sal typhimrium E coli li
buffer egg yolk b ff buffer
2.0 104 8.0 104 9 0 103 9.0
Yeast Sacc cerevisiae
saline
5.0 104
Mold Asp niger
saline
4.7 104 Purwiyatno Hariyadi/ITP530
PENGARUH IRRADIASI PADA MIKROBA Model inaktivasi mikroba oleh irradiasi bisa juga dinyatakan sbb :
N = N0 e
−
D Dn
dimana, dimana, N = jumlah mo setelah iradiasi iradiasi,, = jumlah mo awal (sebelum iradiasi iradiasi), ), N0 D = Dosis radiasi yang diterima diterima,, dan Dn = konstanta k konstanta; t t ; tgt t t jjenis i mo dan d kondisi k di i lingkungan li k Konstanta Dn = dosis radiasi yang menyebabkan kematian mikroba sebanyak 63% populasi populasi..
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
32
07/06/2011 IPN-Dept ITP/IPB
APLIKASI TEKNOLOGI IRRADIASI PADA BAHAN PANGAN Irradiasi dosis rendah (sampai 1 kGy)
Menghambat perkecambahan
(1 Gy = 1 Joule/Kg)
Menunda pematangan buah
Dosis medium (1-10 kGy)
Mengurangi risiko patogen dan meningkatkan masa simpan (keawetan)
Dosis tinggi ( > 10 kGy)
Strilisasi
Purwiyatno Hariyadi/ITP530
APLIKASI TEKNOLOGI IRRADIASI PADA BAHAN PANGAN
Purwiyatno Hariyadi/ITP530
Purwiyatno Hariyadi/IITP530- 2011
33