Trend of Alternative Food Processing Technologies (based on IFT s Report)

(1)

Trend of

Alternative Food

P

i

T

h

l

i

Processing Technologies

(based on IFT’s Report)

Purwiyatno Hariyadi/ITP530

Purwiyatno Hariyadi

(2)

Alternative Food Processing Technologies :

•

Microwave and Radio Frequency

•

Ohmic and Inductive Heating

•

High Pressure Processing

•

P l d El t i Fi ld

•

Pulsed Electric Field

•

High Voltage Arc Discharge

•

Pulsed Light

•

Oscillating Magnetic Fields

•

Ultraviolet Light

•

Ultrasound

(3)

(4)

Berpeluang

mengganggu

Gelombang mikro

Berdekatan dan

Tumpang tindih

Penggunaan MW

perlu diatur

PENGGUNAAN GEL MIKRO (MICROWAVE/MW)

UNTUK KEPERLUAN INDUSTRI :

proses

komunikasi

Tumpang tindih

Dengan kisaran

Gelombang radio

oleh badan

yang berwenang,

Mis.

Di AS : Federal Communication Commission memperbolehkan pemakaian 4 frekuensi MW : 22150, 5800, 2450 dan 915 MHz

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

(5)

dipantulkan oleh metal

diserap (diubah menjadi panas) oleh dielektrik : internal heating (Molecular friction).

PEMANASAN DIELEKTRIK (& GEL MIKRO)

δ

Generator (Oscilator)

+/-Bahan pangan

H

O

δ-δ+

δ+

δ-“Perub. Orientasi polarisasi” Purwiyatno Hariyadi/ITP530

+/-+

+

Ionic displacement

Listrik Konversi Energi Panas

P = 2π(ε

(

oo

)(

)( )

ε’) tan δE2

f

P = 5.56x10

-13 (ε’) tan δE2

_f

P = jumlah panas yang diproduksi per satuan volume [=] W/m3

ε_o= permitivity of free space

ε’ = konstanta dielektrik

(sifat fisik bahan yang berhubungan dengan polaritas atau Σdipole)

δ= loss angle

E = kekuatan medan listrik [=] volts/m f = frekuensi (hz, s-1₎

(6)

LOSS FACTOR

∈ε” = f (SUHU, FREKUENSI)

35 Mashed Potatoes 5 10 15 20 25 30 35 20 40 60 80 100 120 140 160 450 MHz 900 MHz 2700 MH Cooked carrots H2O Purwiyatno Hariyadi/ITP530 -20 0 20 40 60 0 5 -20 20 40 60 0 20 2700 MHz SUHU (o_C) 2 SUHU (o_C)

DAYA PENETRASI GEL MIKRO = d

tan

δ

ε

'

2 π

λ

d

=

o λo= panjang gelombang Kedalaman penetrasi, d[=] cm Kadar air ε’ 915 MHz 2450 MHz tinggi 15 8,4 3,1 sedang 4 11,7 4,4 rendah 1,5 22,1 8,2

(7)

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_{” E}2_f)VΔ_t Jadi, ΔT = 5.56 x 10-13 ε” c E 2_fΔ_t Purwiyatno Hariyadi/ITP530

untuk pemanasan gel mikro yang sama,

ρc

ΔT = ≈ ε”

ρc = f (Komponen bahan pangan)

homogenitas pemanasan = homogenitas bahan pangan

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

(8)

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

Purwiyatno Hariyadi/ITP530 - tidak mengalami case hardening

Biji-bijian : terutama untuk Benih - meningkatkan laju germinasi

Mengeringkan bagian dalam (tanpa overcooked dipermukaan)

APLIKASI PEMANASAN GEL. MIKRO (UMUM):

•Rumah tangga : microwave oven

•Komersial

4

Pemanasan tanpa merubah sifat-sifat dasar produk :

th i & d f i (t i )

thawing & defrosing (tempering)

4

Pemanasan dengan merubah sifat-sifat dasar produk : Pengembangan adonan & pemanggangan

Pemblansiran buah/sayuran : inativasi enzim Pemasakan (cooking)

Roasting (untuk kacang-kacangan)

4

Pengeringan : Dehidrasi pada tekanan normal

4

Pengeringan : Dehidrasi pada tekanan normal Dehidrasi pada tekanan vakum

4

Inaktivasi Mikroba :

Sterilisasi & Pasteurisasi (kurang sukses ! : masih dalam penelitian!)

(9)

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)

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 proses pemanasanp p p p

☺Problem : Pada bahan baku yang ukuran besar - proses pencairan tidak seragam

(10)

APLIKASI PEMANASAN GEL. MIKRO PADA PROSES

DEFROSTING :

Menaikan suhu produk beku: -20o_{C menjadi -3}o_C

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

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)

(11)

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

Umumnya dipakai untuk mengeringkan semi/partly dried foods, dimana gel. Mikro akan tetap memanaskan daerah yang masih basah, tanpa mempengaruhi daerah/bagian yang sudah kering. Mahal

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 waktu proses menurun

(12)

PEMANASAN OHMIC

S

PowerPower Supply Supply BAHAN BAHAN elektroda elektroda

S

SupplySupply P : laju jumlah panas yang diproduksi P : laju jumlah panas yang diproduksi

per satuan volume (W.m per satuan volume (W.m--33₎₎

E : kekuatan medan listrik (Volt cm E : kekuatan medan listrik (Volt cm--11₎₎

k

k_e_e: konduktivitas listrik (ohm: konduktivitas listrik (ohm--11_/m_/m, , _S/m)_S/m)

I : densitas arus listrik (amps/m I : densitas arus listrik (amps/m22₎₎

P = I P = I22_R_R P = I P = I22_k_k e e--11 I = k I = keeELEL--11 Purwiyatno Hariyadi/ITP530 R : tahanan listrik (ohm

R : tahanan listrik (ohm--11₎₎

-- kecepatan pemanasan tergantung pada nilai kkecepatan pemanasan tergantung pada nilai k_e_ebahan panganbahan pangan -- kk_e_ebahan pangan =f(kadar air, garam ionik dan asam)bahan pangan =f(kadar air, garam ionik dan asam)

-- kkeebahan pangan cair >> kbahan pangan cair >> keebahan padatbahan padat

-- minyak dan lemak mempunyai nilai kminyak dan lemak mempunyai nilai keesangat rendahsangat rendah

PERBANDINGAN ANTARA PEMANASAN GEL MIKRO DAN OHMIC PERBANDINGAN ANTARA PEMANASAN GEL MIKRO DAN OHMIC

Kriteria

Kriteria PemanasanPemanasan PemanasanPemanasan Gel Mikro

Gel Mikro OhmicOhmic Konduktivitas listrik

Konduktivitas listrik 0.250.25--44 0.0050.005--1.21.2 (siemen/m)

(siemen/m)

Generasi Panas untuk Generasi Panas untuk medan listrik 20 V/m medan listrik 20 V/m 11--1616 0.020.02--55 (W/cm (W/cm33₎₎ Kenaikan suhu Kenaikan suhu 0.250.25--4*4* 0.0040.004--1.2*1.2* ((oo_C/sec)_C/sec)

* kenaikan suhu di permukaan kaleng pada proses pemanasan * kenaikan suhu di permukaan kaleng pada proses pemanasan

retort adalah sekitar 0.2 retort adalah sekitar 0.2oo_C/sec_C/sec

(13)

Arah perambatan panas, Q Arah perambatan panas, Q

⎤⎤ ⎡⎡ _⎛⎛ _⎞⎞22 2 2 P P == 2 2 Pr Pr Q(r) Q(r) rr ⎥⎥ ⎥⎥ ⎦⎦ ⎤⎤ ⎢⎢ ⎢⎢ ⎣⎣ ⎡⎡ ⎟⎟ ⎠⎠ ⎞⎞ ⎜⎜ ⎝⎝ ⎛⎛ −− == −− ₀₀ 22 R R rr 1 1 4k 4k Pr Pr T T T T

Kenaikan suhu maksimum Kenaikan suhu maksimum

4k

PR

T

2 2 o o max max

−−

==

k = konduktivitas panas k = konduktivitas panas Purwiyatno Hariyadi/ITP530

Kenaikan suhu rata Kenaikan suhu rata--ratarata

4k

8k

PR

T

2 2 0 0

==

−−

Contoh : Contoh :

Sebuah bahan berbentuk silinder dengan diameter 2R dan panjang Sebuah bahan berbentuk silinder dengan diameter 2R dan panjang L. Berapa

L. Berapa Δ Δ voltase (E) yang perlu diberikan supaya terjadi voltase (E) yang perlu diberikan supaya terjadi peningkatan suhu di pusat bahan sebesar (T

peningkatan suhu di pusat bahan sebesar (Tmaxmax--TT00))ooC, dimana suhu C, dimana suhu

awal = T awal = T00.. J b J b

T

PR

2 2

==

Jawab : Jawab : Gunakan Gunakan persamaan persamaan peningkatan suhu peningkatan suhu

k

R

E

R

L

E

k

T

ee 2 2 2 2 2 2 2 2 2 2 e e 0 0 max max

⎟⎟

_⎠⎠

⎞⎞

⎜⎜

⎝⎝

⎛⎛

⎟⎟⎟⎟

⎠⎠

⎞⎞

⎜⎜⎜⎜

⎝⎝

⎛⎛

==

⎟⎟

⎠⎠

⎞⎞

⎜⎜

⎝⎝

⎛⎛

==

−−

L

E

k

II

,,

k

4k

R

II

T

ee e e 2 2 2 2 0 0 max max

−−

==

4k

T

_max_max

−−

₀₀

==

))

T

(T

T

k

R

L

2

2 E

E

Jadi,

0 0 max max 0 0 0 0 e e

−−

⎟⎟

⎠⎠

⎞⎞

⎜⎜

⎝⎝

⎛⎛

==

k

4L

k

4k

_e_e 22 0 0 max max

⎟⎟

⎜⎜

_⎝⎝

⎟⎟

_⎠⎠

⎠⎠

⎜⎜

⎝⎝

(14)

Vs PEMANASAN OHMIC & GELOMBANG MIKRO Vs PEMANASAN OHMIC & GELOMBANG MIKRO

Mirip dengan pemanasan gel. Mikro : Mirip dengan pemanasan gel. Mikro : Mirip dengan pemanasan gel. Mikro : Mirip dengan pemanasan gel. Mikro :

Konversi enegi listrik menjadi energi panas Konversi enegi listrik menjadi energi panas Penetrasi panas/daya penetrasi : tidak terbatas Penetrasi panas/daya penetrasi : tidak terbatas Suhu dalam bahan pangan merata (

Suhu dalam bahan pangan merata (∇∇T T ≈≈0)0) Tidak perlu “pengadukan”

Tidak perlu “pengadukan”

Cocok untuk memanaskan bahan pangan cair dgn partikulat : Cocok untuk memanaskan bahan pangan cair dgn partikulat :

sop dll. sop dll.

(15)

Bahan

Bahan nilai knilai kee(s/m)(s/m)

Air murni (25

Air murni (25oo_C)_C) _5,7x10_5,7x10--66

Nilai konduktivitas listrik beberapa bahan

Air murni (25 Air murni (25 C)C) 5,7x105,7x10 Asam sulfat (25 Asam sulfat (25oo_C)_{C) 1}₁ kentang(19 kentang(19oo_C)_C) _0.037_0.037 wortel (19 wortel (19oo_C)_C) _0,041_0,041 kacang kapri (19 kacang kapri (19oo_C)_C) _0.17_0.17 daging sapi (19 daging sapi (19oo_C)_C) _0,42_0,42 Larutan pati (5 5% 19 Larutan pati (5 5% 19oo_C)_C) Purwiyatno Hariyadi/ITP530 Larutan pati (5,5%, 19 Larutan pati (5,5%, 19 C)C) + garam 0.2% + garam 0.2% 0,340,34 + garam 0,55% + garam 0,55% 1,31,3 + garam 2% + garam 2% 4,34,3

(16)

Elektroda 4

KONFIGURASI SISTEM PEMANAS OHMIC

Elektroda 3

Elektroda 1 Elektroda 2

Purwiyatno Hariyadi/ITP530 Elektroda 2

(17)

(ULTRA) HIGH

PRESSURE

PROCESSING

~

HIGH

HYDROSTATIC

PRESSURE

(18)

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,

t f it

d

t bl

meat, fruits and vegetables.

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.

High hydrostatic pressure

• Foods "pasteurized" by HHP undergo pressures of

Foods 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

d A i i

l d j i

j

j lli

t

Europe and Asia include juices, jams, jellies, meat

and yogurts.

• Consumers in this country can buy HPP-processed

guacamole and oysters.

(19)

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

cents per pound) than for conventional processes.

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.

(20)

HHP processing

• High Pressure can kill microorganisms by

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.

HHP processing

• The "mechanism" of high-pressure based bacteria kill is low

d d

t

t th f

ti

f

h

i

l

energy and does not promote the formation of new chemical

compounds, "radiolytic" by-products, or free-radicals.

• Vitamins, texture and flavor are basically unchanged.

• For example, enzymes can remain active in high pressure

(21)

HHP system

• This 35-liter high-pressure

b t h

it f

Fl

batch unit from Flow

International can process up to

700 lbs. an hour and is

designed for prepackaged

products such as bottled

juices.

• Units with capacities up to 300

p

liters are available.

• Food scientists are optimistic

about hydrostatic pressure's

ability to extend shelf life and

produce safe food

.

(22)

Industrial High Pressure Food Processors

Complete systems are offered for bulk and in container

processes.

P

ti

Applications for High Pressure Processing are

found in the areas of...

Preservation

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)

(23)

Food safety

Applications for High Pressure Processing are

found in the areas of...

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

• Juice tests have shown that food

Fruit Juice treated with HHP

Applications for High Pressure Processing are

found in the areas of...

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

A pressure exposure of 80,000 psi

for 30 seconds can achieve a 3-5

log reduction of all of the

(24)

• Another example of food safety is the

Oyster treated by HHP

Applications for High Pressure Processing are

found in the areas of...

p y

destruction of Vibriobacteria 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 parahaemolyticusATCC 17803, ·Vibrio vulnificusATCC 27562,

· Vibrio choleareATCC 14035,

· Vibrio cholearenon-O:1 ATCC 14547, · Vibrio hollisaeATCC 33564

· Vibrio mimicusATCC 33653

(from: "D. Berlin, D. Herson, D. Hicks, and D. Hoover; Applied and Environmental Microbiology, June 1999“)

Oyster treated by HHP

Applications for High Pressure Processing are

found in the areas of...

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 and increasing production g p efficiency.

(25)

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.

Commercial High-Pressure Processed products

marketed in Japan, Europe and the United States

Guacamole & Salsas Avomex (Keller, TX)

(26)

Commercial High-Pressure Processed products

marketed in Japan, Europe and the United States

Commercial High-Pressure Processed products

marketed in Japan, Europe and the United States

Jams & Fruit Toppings

(27)

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

Texturization

Applications for High Pressure Processing are

found in the areas of...

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.

(28)

H

t

iti

d

Applications for High Pressure Processing are

found in the areas of...

Heat-sensitive compounds

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.

Thermally-assisted high-pressure lifts quality of shelf-stable

foods

Process Variables for Optimum Quality

Tempera-t Pressure Products ture

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

(29)

Effect of pressure is very similar to the effect

of temperature in thermal processes

Purwiyatno Hariyadi/ITP530 Figure. Change in inactivation of Zygosaccharomyces bailiiwith pressure. Note that 345 MPa = 50,000 psi. (Enrique Palou, GRA, BSysE Dept., WSU)

Two things must be done.

Thermally-assisted high-pressure lifts quality of shelf-stable foods

What's needed to commercialize UHP for sterilizing shelf-stable

products?

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.

(30)

•• Dikendalikan oleh “the International Commission on Dikendalikan oleh “the International Commission on Radiological Units”

Radiological Units” RadRad

•• 1 Rad = jumlah irradiasi yang menyebabkan 1 g bahan yang1 Rad = jumlah irradiasi yang menyebabkan 1 g bahan yang

Dosis Irradiasi

1 Rad jumlah irradiasi yang menyebabkan 1 g bahan yang 1 Rad jumlah irradiasi yang menyebabkan 1 g bahan yang diirradiasi akan menyerap energi sebesar 100 erg (1 Rad = 100 diirradiasi akan menyerap energi sebesar 100 erg (1 Rad = 100 erg/g)

erg/g)

•• Satuan umum Satuan umum “Grey“ “Grey“

•• 1 Grey = jumlah irradiasi yang menyebabkan 1 kg bahan yang 1 Grey = jumlah irradiasi yang menyebabkan 1 kg bahan yang diirradiasi akan menyerap energi sebesar 1 joule;

diirradiasi akan menyerap energi sebesar 1 joule;

•• 1,000 Grey = 1 kGy.1,000 Grey = 1 kGy.

Purwiyatno Hariyadi/ITP530 , y y , y y •• 100 Rad = 1 Gy 100 Rad = 1 Gy

Dosis Irradiasi

(31)

PENGARUH IRRADIASI PADA MIKROBA

D10: dosis irradiasi

yang menyebabkan pengurangan jumlah mikroba dengan faktor 10

D10dose

D_{10,veg bacterium}

D10,yeast

PENGARUH IRRADIASI PADA

MIKROBA

_Organism

_{Organism D}

_D

value

(32)

_______________________________________________________ organisme medium in D₁₀(Rad)

which irradiated

_______________________________________________________ Bacterial spore

PENGARUH IRRADIASI PADA MIKROBA

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 buffer 2.0 104

egg yolk 8.0 104

E li b ff 9 0 103

E coli buffer 9.0 103

Yeast

Sacc cerevisiae saline 5.0 104

Mold

Asp niger saline 4.7 104

Model inaktivasi mikroba oleh irradiasi bisa juga dinyatakan sbb : Model inaktivasi mikroba oleh irradiasi bisa juga dinyatakan sbb :

D D

PENGARUH IRRADIASI PADA MIKROBA

n n D D D D

e

N

₀₀

N

−−

==

dimana dimana, , N

N = = jumlahjumlah mo mo setelahsetelah iradiasiiradiasi, , N

N00 = = jumlahjumlah mo mo awalawal ((sebelumsebelum iradiasiiradiasi), ),

D

D = = DosisDosis radiasiradiasi yang yang diterimaditerima, , dandan D

D kk tt tt t tt t jj ii dd kk di idi i lili kk D

Dnn = = konstantakonstanta; ; tgttgt jenisjenis mo mo dandan kondisikondisi lingkunganlingkungan

Konstanta

Konstanta DDnn= = dosisdosis radiasiradiasi yang yang menyebabkanmenyebabkan kematiankematian mikrobamikroba

sebanyak

(33)

Menghambat perkecambahan Irradiasi dosis rendah

(sampai 1 kGy)

APLIKASI TEKNOLOGI IRRADIASI

PADA BAHAN PANGAN

Mengurangi risiko patogen dan

meningkatkan masa simpan (keawetan) Dosis medium (1-10 kGy)

Menunda pematangan buah

(1 Gy = 1 Joule/Kg)

Strilisasi Dosis tinggi ( > 10 kGy)

simpan (keawetan)