Fisiologi dan Teknologi Pascapanen (TPP 2612) Pengaturan Pemasakan
Dr. Ir. Djagal W. Marseno, M.Agr
RIPENING, DEGREENING AND COLOR ADDING Mempercepat Pemasakan
Pengaturan Pemasakan
Ripening : adalah proses terbentuknya semua karakteristik buah masak yang diinginkan p. 135
• Pemberian ethylene/acethylene • Menurunkan CO2 • Luka • Stress
Alamiah
Menunda Pemasakan • Meningkatkan CO2 • Menurunkan O2 • Menurunkan suhu • Blocking produksi ethylene • Inhibitor ethylene
Pemasakan (ripening) • Ripening adalah proses terbentuknya semua karakteristik buah masak (ripe) yang diinginkan • Pemicu : ethylene sebagai hormon pemicu kematangan • Ciri : • Tekstur Lunak • Rasa Tidak asam, manis, tidak sepet/pahit • Flavor Aromatic, spesific • Warna spesific kuning, merah, dsb • Respiration is the process by which stored organic materials (carbohydrates, proteins, fats) are broken down into simple end products with a release of energy. • Climacteric fruits show a large increase in CO2 and ethylene (C2H4) production rates coincident with ripening, • Non-climateric fruits show no change in their generally low CO2 and C2H4 production rates during ripening.
p. 135
Klasifikasi buah berdasarkan proses pemasakan Climacteric fruits
Klasifikasi buah
• Fruits that can be picked mature green and ripened after harvest • Containing high amounts of starch that can be converted into sugars • The color and flavor develop further after harvest • Ripening rate can also be hastened • Rise in respiration when it starts to ripen which declines slightly before
Non-climacteric fruits
p. 135
Klasifikasi buah berdasarkan proses pemasakan Climacteric fruits
Klasifikasi buah Non-climacteric fruits
p. 135
• Fruits that have to be picked ripe • Have no starch to be converted into sugars • They have to be picked ready to eat as there is no further development of flavor after harvest • hardly no change in respiration after harvest • degreening process by ethylene to yellow orange
CO2 Production
Pola Perubahan Respirasi (Patterns of ripening)
Climacteric
Non-Climacteric
Times of harvest (days)
Pola Perubahan Etilen pada Buah Climacteric
Mechanism of ripening Enzyme inhibitor decrease
Ethylene Increased / Applied
Many Enzyme Increase in amount Or synthesized Increase Ethylene Production
Respiration Shoots up
Breakdown of Protein and Lipids
Enzymes gets more in contact with Substrates
Changes tissue permeability
Decreased in acids
Breakdown of Hemicellulose & starch
Conversi on of Protopec tin to Soluble pectins
Synthesis of Carotenoids & Other pigments
Sweetness Cell wall Cellulose Structure Loosens up
Separation of cell Along middle lamella
Softening
Breakdown of chlorophyll
Synthesis of volatiles
Color change Development of aroma
Breakdown of tannins
Loss of Astringency (contribute to Flavor)
Climacteric & Non-Climacteric Non-Climacteric • grape • pineapple • rambutan • strawberry • mandarin • oranges • longan • cashew • lemon • salak
Climacteric • banana • avocado • mango • papaya • watermelon • tomato • guava • jackfruit
Advantages of Accelerated Ripening 1. Mempermudah transportasi, karena buah yang matang hijau lebih stabil terhadap kerusakan mekanik dibanding buah masak 2. Menjamin terbentuknya warna seragam yang maksimum menyeluruh 3. Mengurangi susut pascapanen 4. Mempercepat pengembalian modal usaha 5. Menjaga stabilitas harga jual yang tinggi sepanjang tahun 6. Mempermudah proyeksi volume penjualan 7. Meningkatkan efisiensi penggunaan gudang penyimpanan
Justification for Degreening 1. Meningkatkan harga jual • Light green yellow • Green orange 2. Meningkatkan derajat penerimaan konsumen
General Technique for Accelerated Ripening & Degreening 1. Menambahkan ethylene dan / atau acetylene di ruang penyimpanan buah • Ethylene • Ethylene-releasing compound (2-chloroethyl phosphonic acids ethephon (ethrel) • Acethylene-releasing compound (calcium carbide) 2. Membuat buah menjadi stress untuk menghasilkan ethylene stress. • Luka (wound) • Suhu tinggi 3. Expose to bioethylene (from leaves or fruits)
Perbedaan dan Persamaan Teknik Accelerated Ripening & Degreening 1. Persamaan : • Menggunakan ethylene/acetylene 2. Perbedaan : • Waktu yang digunakan • Ripening shorter time (12 – 48 hours) • Degreening longer time (3 – 7 days) 3. Alasan : • Dalam buah climacteric yang terpenting adalah tahap memicu produksi ethylene secara autocatalytic • Pada jeruk, ethylene harus selalu ada di lingkungannya sampai kulit yang berwarna hijau menjadi kuning (degreening)
Requirement for Ripening A. Dari segi buah : • Buah harus matang (mature) • Buah tidak cacat / infected B. Dari segi Ruangan : • Kedap udara • Suhu rendah (avocado : 16-24 oC; banana : 1420 oC; mango : 21-24 oC; papaya : 18 – 21 oC; tomat 15 oC) • Dinding berisolasi baik terhadap perubahan suhu • Memiliki ventilasi dan sirkulasi udara yang baik • Memiliki pengendalian humidity yang baik • Memiliki pengaturan gas ethylene yang baik • Memiliki pintu darurat
Effect of CO2 on Ripening immature stage
mature stage (matang)
ripening stage (masak) Enzyme O2
Enzyme
Enzyme
O2
O2
C2H4
Ripening initiated
Enzyme Binding site for Ethylene developed
O2
CO2
Ripening inhibited
Effect of Karbit on Ripening (2.000 oC) CaO(s) + C(s) Ca-oksida Kokas (arang C)
CaC2(s) + 2H20(l) Ca-Carbide
CaC2(s) + H20(l) Ca-Carbide
CaC2(l) + CO(g) Ca-Carbide
Ca(OH)2(aq) + C2H2(g) Acetylene (etuna)
CaO(aq) + C2H2(g) Ca-oxide Acetylene (etuna)
Amount of Carbide for Ripening Fruits Fruits
Amount
Mango
• 1 g/kg fruits
Banana (in general)
• 1 g / 12 air space for 24 -36 hours • 60 g/208 L container for 24 – 48 h
Saba banana
• 5 – 20 g/230 L container for 24 h
Bungulan banana
• 10 – 60 g/230 L container for 24 h
Chico
• 3 g / 60 g in basket for 12 – 18 h
Classification of fruits based on ethylene production Level
Very Low
Low Moderate High Very High
Ethylene production rate range at 20°C (68°F) (ml C2H4/kg-hr)*
Fruits
< 0.1
Artichoke, asparagus, cauliflower, cherry, citrus fruits, grape, jujube, strawberry, pomegranate, leafy vegetables, root vegetables, potato, most cut flowers
0,1 – 1,0
The non-climateric fruits : Blackberry, blueberry, casaba melon, cranberry, cucumber, eggplant, okra, olive, pepper (sweet and chili), persimmon, pineapple, pumpkin, raspberry, tamarillo, watermelon
1,0 – 10,0
Tomato, avocado, honeydew melon Banana, fig, guava, melon, lychee, mango, plantain,
10,0 – 100,0
Papaya, avocado, chico, banana, fig, guava, honeydew melon, lychee, mango, plantain, tomato Apple, apricot, avocado, cantaloupe, feijoa, peach, pear, kiwifruit (ripe), nectarine
> 100,0
Passion fruit (Cherimoya, mammee apple, passion fruit, sapote)
Factors affected on ethylene production 1. Maturity at harvest; 2. Physical injuries; 3. Disease; 4. High or low temperature; and 5. Water stress
Factors affected on ethylene reduction 1. Reducing the storage temperature; 2. Reducing O2 levels to less than 8%; 3. Treating with the inhibitors AVG, AOA or cobalt chloride; or 4. Genetic engineering (using antisense technology).
Blocking of ethylene action
1. Treating with silver thiosulphate (commonly used in flowers); 2. Hypobaric storage - keeping the commodity under vacuum; 3. Elevating CO2 to more than 2%; or 4. Genetic engineering (blocking the ethylene receptor).
Treatment with Ethylene Gas 1. Cost and availability • Mahal bagi industry kecil • Impor dari Singapore, Thailand and Malaysia 2. Concentration • Treshold level in fruit : 0,2 – 1,0 ppm • Applied at the lowest possible level, and the shortest possible time just to trigger the autocatalytic ethylene concentration • Degreening : 100 – 1.000 ppm 3. Danger • Explosive at 30.000 ppm (3 %) 4. Methods of application • Intermittent method (every 6-8 hours) • Continuous ventilation
Treatment with Ethephon (Ethrel) 1. Cost and availability • Relative murah dibanding ethylene 2. Concentration • Commercially 4 lbs/gal 480 g/L • pH 1-4 (stable). pH > 4 ethylene liberated • Concentration : 2.500 – 5.000 ppm
Color adding 1. Definition • Application of a dye to pale colored oranges to improve color in addition to greening 2. Requirement • Only mature oranges • The dye is safe for health. FDA Citrus Red No. 2. allowable residue : 2 ppm 3. Condition • 4 minuts 49 oC. • No injured fruits should be treated • The water : low in sulfur and iron, pH slightly alkaline • Equipment and water should be clean • 1 galon of dye + 300 gal of water • Grade and degreening before color adding • Rinse after color adding
Fisiologi dan Teknologi Pasca Panen (TPP 2612)
PENYIMPANAN SUHU RENDAH
Dr. Ir. Djagal W. Marseno, M.Agr
1. Penyimpanan Suhu Rendah 2. Penyimpanan Suhu Optimum 3. Pengaruh Suhu dan Waktu Penyimpanan terhadap Mutu Produk
Precooling (pre-refrigeration)
Cooling (Refrigeration)
• rapid cooling (48 hours or less) of a commodity soon after harvest to a desired storage temperature • cooling prior to refrigerated storage or transport
Benefit from Precooling 1. The time needed to attained the temperature of the refrigerated space is lesser 2. Minimize refrigeration load 3. Allows ripe fruits to be transported or stored 4. Permits havier loading of refrigerated transport vehicle
HEAT AND ENERGY solid Temperature : - 5 oC
State : ice Type of heat involved :
liquid 0 oC
0 oC
5 oC
ice
liquid
liquid
sensible heat
sensible heat Latent heat of fusion
gas 100 oC 100 oC
150 oC
vapor
vapor
liquid sensible heat
sensible heat Latent heat of vaporization
• Latent heat : the heat required to transform water from ice to water and from water to vapor without any change in temperature • Latent heat of fusion : heat required to transform water from ice to liquid water • Latent heat of vaporization : heat required to transform water from liquid water to vapor • Sensible heat : heat needed to raise the temperature without any change in state
Some terms 1. Evaporation takes place at a lower temperature when the pressure is low. In other words, boiling point is lowered at lowered pressure 2. Vapor moves from high pressure area to a low pressure area 3. When a surface is colder than the air, then the air condenses on the surface.
Methods of Precooling 1. Room cooling 2. Forced air cooling or Pressure cooling 3. Hydrocooling 4. Wet air cooling 5. Vacuum cooling 6. Hydrovacuum cooling 7. Contact ice
Methods and commodities Precooling method
Commodities
Room cooling
All commodities
Hydrocooling
Commodities that are not harmed by prolonged contact with water : leafy vegetables, asparagus, sweet corn, celery, topped carrot
Vacuum cooling
Best for products with a higher surface area to weight or volume ratio : celery, parsley, letuce, other leafy vegetables
Package icing
Commodities that needed temperatures close to 0 oC: lettuce and other leafy vegetables, carrot, cauliflower, broccoli, asparagus, young cob corn
Determining the rate of cooling 1. Half cooling time : the length of time it takes to reduce the temperature difference between the commodity and the water or air coolant by half 2. It is used to estimate cooling time 3. Practical cooling time usually 3 – 8 half cooling time. 4. Half cooling time is 3 hours practical cooling time is 9 hours 5. Example : T of commodity : 30 oC, T in room cooler 4 oC half cooling time = 30 – {(304)/2} = 17 oC.
Factors determining the rate of precooling 1. Accessibility of the commodity to the cooling medium 2. Temperature difference between the product and the cooling medium 3. Velocity of movement of the cooling medium 4. Rate of heat transfer from product to cooling medium. • Depend on shape and size (surface to volume/mass ratio) • Thermal properties spesific heat and thermal conductivity. • •
Spesific heat : the amount of heat (BTU) to raise the temperature of l lb of commodity 1 oF Thermal conductivity : ability of the substance to transfer heat
Determining the rate of cooling 1. Half cooling time : the length of time it takes to reduce the temperature difference between the commodity and the water or air coolant by half 2. It is used to estimate cooling time 3. Practical cooling time usually 3 – 8 half cooling time. 4. Half cooling time is 3 hours practical cooling time is 9 hours 5. Example : T of commodity : 30 oC, T in room cooler 4 oC half cooling time = 30 – {(304)/2} = 17 oC.
Applicability of precooling in developing countries 1. Distance. • Short and long distance • Type of equipment 2. Altitude : precoolers are more useful in lowlands than in highlands 3. Precooling is practical only with high value, perishable products
REFRIGERATED STORAGE AND TRANSPORT
REFRIGERATED STORAGE AND TRANSPORT 1. Definition of Refrigeration • Proses pemindahan panas dari suatu ruang atau bahan untuk menurunkan suhunya dan menjaganya pada tingkat suhu yang diinginkan 2. Objective of Refrigeration • Untuk memindahkan panas dari product dengan cepat agar (1) dapat menurunkan metabolisme ke tingkat minimum sehingga dapat menunda kerusakan dan kebusukan; (2) memungkinkan untuk menjual dan menggunakan produk pada hari berikutnya • Memperluas jangkauan pasar, menghindari melimpahnya produk dipasar, membatasi susut / kehilangan
Persyaratan Ruang Pendingin 1. Kapasitas pendingin harus cukup • Jumlah panas yang dikeluarkan oleh sistem pendingin dalam waktu tertentu harus memadai 2. Sirkulasi udara harus cukup 3. Dinding penyekat harus sesuai • Dapat membatasi pertukaran panas antara bagian dalam ruang pendingin dan lingkungan luar
Pertimbangan penggunaan pendinginan 1. Keuntungan produk • Harga jual produk (mahal) 2. Lokasi ruang pendingin • Dekat dengan pusat produksi atau pasar
Sebab-sebab yang dapat memperpendek umur simpan 1. Serangan mikrobia 2. Berkembangnya ketidakteraturan prosesproses fisiologis 3. Hilangnya kemampuan untuk masak secara normal setelah panen 4. Kehilangan air karena : • Immaturity, • delayed storage, • placing very hot fruit in the storage, • hot spot in the store, • low humidities, • slow cooling, • and excessive air circultion
Determining When to Terminate Storage Length of storage varies depending on : • Kind and quality of product • Variety • Preharvest history • Condition in the store
Greening of Potatoes • Formation of solanine (bitter and potentially toxic compound) • 1 – 5 mm from surface • Depend on how long the lights are turn on during storage
Physiological Disorders during Low Temperature Storage 1. Greening of potatoes 2. Chilling injury 3. Ammonia injury
Physiological Disorders during Low Temperature Storage 1. Greening of potatoes 2. Chilling injury 3. Ammonia injury
Greening of Potatoes • Formation of solanine (bitter and potentially toxic compound) • 1 – 5 mm from surface • Depend on how long the lights are turn on during storage
Chilling Injury Terbentuknya bintik-bintik hitam pada permukaan bahan yang didinginkan pada suhu dibawah suhu yang diperlukan selama waktu tertentu
a. Symptoms : • Gejala timbul setelah komoditi disimpan pada suhu dibawah suhu yang diperlukannya untuk periode tertentu lalu dikeluarkan dari ruang dingin • Terutama terjadi pada komoditi tropis • Gejala umum (common symptoms) • Bintik hitam dipermukaan bahan • Perubahan warna internal bahan • Gagal untuk masak, masak tidak merata • Meningkatkan kerentanaan terhadap penyakit • Timbulnya rasa manis pada kentang • Off-flavor
CHILLING INJURY & FREEZING INJURY Chilling T : 5 – 12 oC
Suhu terendah aman bagi bahan (suhu kritis)
Simptom (tanda) bahan
Freezing T : - 0 oC
MEKANISME CHILLING INJURY (CI)
Suhu
Lipid bilayer Fluidity / tekstur • Enzim + substrat • Asam-asam organik • Tumbuh mikroorganisme
Simptom CI: • Bintik coklat • Tekstur lunak • Pembusukan
Mechanism of Chilling Injury
Chilling temperature
pitting
Formation of Toxic compound
Membrane permeability changes
Disruption of chemical reactions
Respiratory changes
Reduced energy level
Water loss
Disruption of cyclosis
Failure to ripen
Death of cells
Water soaking
Discolorization
Suscept ability to decay
Simptom Chilling Injury Bahan segar
Suhu terendah aman rata-rata (oC)
Alpukat
5 – 12
Pisang Ketimun Terong Lemon
12 7 7 10
Lime Mangga Melon Pepaya Nanas Tomat
7 5 – 12 7 – 10 7 6 – 10 7 - 12
Commodity and cultivar • Bintik-bintik berlubang, pencoklatan pulp dan jaringan vaskulter • Bercak-bercak coklat pada kulit • Warna gelap, banyak bagian berair • Busuk permukaan • Bintik-bintik pada flavedo pewarnaan membrane, dan bercak merah • Bintik-bintik • Kulit jelek, pencoklatan pada areal tertentu • Bintik-bintik, busuk permukaan • Jaringan coklat atau hitam • Bintik-bintik, busuk Alternaria
Chilling Injury b. Overcoming Chilling Injury : • Suhu ketika precooling • Penyimpanan dalam CAS, MAS atau hypobaric storage (low O2 and high CO2 banana : 3 - 4% O2 dan 0 - 5% CO2) • Penyimpanan dalam RH tinggi • Ca treatment (CaCl2 1 - 7,5%) c. Keuntungan mengatasi Chilling Injury : • Pemasakan buah dapat dikendalikan • Penyakit yang diakibatkan jamur dapat ditekan (misal Rhizopus) • Penyakit yang diakibatkan insekta selama karantina dapat dihambat
Ammonia Injury a. Penyebab : • Kebocoran ammonia dalam ruang penyimpanan ( 0,8% selama satu jam telah menyebabkan kerusakan pisang dan onion) b. Symptoms : • Pada tingkat ringan : terbentuknya warna coklat sampai hitam kehijauan pada permukaan bahan • Pada tingkat lanjut : terjadinya perubahan warna dan pelunakan jaringan bahan bagian dalam unmarketable c. Pencegahan : • Memberikan aerasi ruang yang baik • Treatment dengan sulfur dioxide < 1% (pada grape)
Post Refrigeration Storage a. Symptom : kondensasi uap air pada permukaan bahan b. Penyebab : • terjadi jika komoditi dingin ditaruh pada suhu ruang dengan humidity tinggi • Suhu dimana terjadi kondensasi uap air disebut dewpoint. Udara jenuh dengan uap air c. Pencegahan : • Bahan dingin ditaruh pada ruang yang memiliki suhu dibawah dewpoint udara. Contoh : Suhu ruang diluar cold storage 25 oC, RH 80%. Suhu komoditi harus > 21,5 oC. Jika sama atau kurang akan terjadi kondensasi. • Keluarkan komoditi pada tengah malam atau dini hari • Sirkulasikan udara kering hangat (fan / blower)
Dewpoint temperature Tempe rature of air (oC)
Relative Humidity of Environment (%) 50
55
60
65
70
75
80
85
90
95
20
9.0
10.5
12.0
13.5
14.5
15.5
16.5
17.5
18.3
19.2
21
10.2
11.8
13.0
14.5
15.5
16.5
17.5
18.3
19.5
20.2
22
11.0
12.2
14.0
15.3
16.5
17.5
18.3
19.5
20.5
21.2
23
12.0
14.0
15.0
16.2
17.3
18.3
19.5
20.5
21.5
22.2
24
13.0
14.5
16.0
17.0
18.3
19.5
20.5
21.5
22.2
23.2
25
14.0
15.5
17.0
18.0
19.2
20.5
21.5
22.3
23.2
24.0
26
15.0
16.5
17.7
19.0
20.3
21.5
22.3
23.3
24.2
25.3
27
16.0
17.3
18.5
20.0
21.2
22.3
23.3
24.5
25.3
26.2
28
16.8
18.0
20.0
21.0
22.0
23.3
24.5
25.3
26.5
27.3
29
17.7
19.2
20.6
21.8
23.0
24.5
25.5
26.5
27.3
28.3
30
18.5
20.3
21.5
23.0
24.0
25.3
26.5
27.5
28.3
29.2
31
19.5
21.0
22.4
23.8
25.0
26.2
27.2
28.3
29.2
30.0
32
20.3
22.0
23.3
24.6
26.0
27.2
28.3
29.3
30.3
31.0
33
21.3
22.8
24.3
25.6
27.0
28.2
29.3
30.3
31.0
32.0
34
22.3
23.5
25.3
26.5
28.0
29.0
30.3
31.2
32.2
33.0
35
23.0
24.6
25.1
27.5
28.8
30.0
31.3
32.1
33.2
34.0
Supplements to Refrigeration 1. Irradiation • sinar gamma, sinar x, elektron • Dosis : 3 s/d 75 Kgy (kilogray) • Benefit : • Enzyme inactivation delayed ripening • Controls fruit fly • Minimize deterioration • Inhibit sprouting, prevents rotting of potatoes, garlic, onions.
Supplements to Refrigeration 2. Chemical treatments • Cytokinins : retard chlorophyll degradation, maintain high protein level, delaying yellowing • Gibberelins : lower respiratory rate, delayed color change, retardation of ripening • Auxins – β – nathoxyacetic acid : reduced weight loss, retain ascorbic acid lower deterioration • Calsium : (by infiltration) delayed ripening • Succinamic acid 2-2 dimethyl hydrazide : delayed yellowing and discolorization • Ethylene oxide : (kadar 0,75%) retarded ripening of tomatoes (endogeneous antagonist of ethylene)
Supplements to Refrigeration 3. Modified Atmosphere Storage / Packaging : • Penyimpanan komoditi dalam ruang/kemasan yang memiliki komposisi gas berbeda dengan udara normal • Komposisi O2 and CO2 dikendalikan • O2 : 21 % 5 % • CO2 : 0.03 % 3 – 5 % • respiration in an enclosed system 4. Low pressure (Hypobaric) storage / packaging : • The lower the pressure the lower O2 the lower ethylene production • Normal pressure : 1013 mb to 101.3 mb 02 lowered from 21 to 2.1 %, ethylene production reduced to 1/10
Banana
Apple • core or flesh browning, fermented flavour, spongy texture, susceptibility and symptoms vary with cultivar • Chilling injury < 2oC
Tomato
• • • • •
rubbery texture watery flesh irregular ripening seed browning surface pitting
• Chilling injury
< 10oC
Mango • greyish skin discolouration, pitting, uneven ripening, poor flavour, increased susceptibility to Alternaria rot • Chilling injury < 12oC
Papaya •
pitting, blotchy coloration, uneven ripening, skin scald, hard core (hard areas in the flesh around the vascular bundles), water soaking of tissues, and increased susceptibility to decay.
•
Chilling injury < 7oC
Guava The symptoms of chilling injury in guava: • Brown color in guava peel • Dark spot in fruit surface
Fisiologi dan Teknologi Pasca Panen (TPP 2612)
PENYIMPANAN ATMOSFIR TERKENDALI (Controlled Atmosphere Storage)
Dr. Ir. Djagal W. Marseno, M.Agr
CONTROLLED ATMOSPHERE STORAGE (CAS) NORMAL STORAGE
Normal atmosfir : O2 : 21 % CO2 : 0.03 % N2 : 78%
Controlled Atmosphere Storage
CAS: O2 CO2 N2
Komoditi Living tissues: • Respiration • ethylene production
:1-5% : 0,5 - 5 % :
Komoditi
Respirasi Makromolekul organik : • Karbohidrat • Protein • Lemak
Oksigen Suhu, waktu
Mikromolekul organik :
• CO2 • H2O • Energi
Respiration is defined as the process by which stored organic materials (carbohydrates, proteins, fats) are broken down into simple end products with a release of energy. Oxygen is used in this process and carbon dioxide is liberated. C6H12O6 glucose oksidasi
+
6O2 oxygen reduksi
6CO2 + carbon dioxyde
6H2O + water
686 kcal energy Required for essential processes within the cell
DAMPAK O2 RENDAH DALAM JARINGAN BUAH & SAYURAN
• IB : Internal Breakdown • ACC oksidase
• Udara terkendali dapat mempengaruhi respirasi pada 3 tingkat, respirasi aerobik, anaerobik dan kombinasi dari keduanya • Respirasi aerobik berlangsung bila persediaan O2 nya normal dan menghasilkan pembebasan CO2 dan air • Respirasi anaerobik : pernafasan yang berlangsung tanpa O2 sama sekali yang menghasilkan CO2 dan etil alkohol melalui fermentasi • Bila O2 sedikit kedua proses berlangsung dan bergantung pada konsentrasi relatif O2
Effect of CO2 on Ripening immature stage
mature stage (matang)
ripening stage (masak) Enzyme O2
Enzyme
Enzyme
O2
O2
C2H4
Ripening initiated
Enzyme Binding site for Ethylene developed
O2
CO2
Ripening inhibited
Kandungan CO2 dalam sel yang tinggi mengarah ke perubahan-perubahan fisiologi sebagai berikut: 1. Menurunan reaksi-reaksi sintesis pematangan (protein, zat warna) 2. Menghambat beberapa kegiatan enzimatik 3. Menurunkan produksi senyawa aromatik 4. Mengganggu metabolisme asam organik terutama penimbunan asam suksinat 5. Memperlambat pemecahan zat-zat pektin 6. Menghambat sintesis klorofil dan penghilangan warna hijau, terutama setelah pemanenan dini 7. Mengubah perbandingan berbagai gula
CONTROLLED ATMOSPHERE STORAGE (CAS) Controlled Atmosphere Storage
Advantages of Gas Storage : •
•
CAS O2 CO2 N2
:5% :3-5% :
•
•
Komoditi
Secara umum dapat memperpanjang umur simpan dibandingkan penyimpanan biasa maupun penyimpanan dingin saja tanpa kombinasi CA Buah-buah yang sedikit lewat masak dapat disimpan lama tanpa mengurangi umur simpan Mengurangi sensitivitas buah terhadap ethylene maupun chilling injury pada suhu dibawah suhu optimum delayed ripening No problem of insects and rodents, mold growth
Disadvantages : • •
Expensive Need technical knowledge to run
CONTROLLED ATMOSPHERE STORAGE (CAS) Controlled Atmosphere Storage
Persyaratan Ruang untuk CAS : •
CAS O2 CO2 N2
• •
:5% :3-5% :
• •
Komoditi
• •
Sufficient gas tightness. Pasokan O2 harus dibawah kebutuhan untuk respirasi Insulation against heat loss Accurate control of the desired gas concentration. Too low O2 anaerobic respiration; too high CO2 injure fruits Good air circulation Small access door for emergency escape, sampling and inspection Memiliki vent valve Memiliki peralatan lengkap (thermometer, gas meter, light)
CONTROLLED ATMOSPHERE STORAGE (CAS) Controlled Atmosphere Storage
Persyaratan Ruang untuk CAS : •
CAS O2 CO2 N2
• •
:5% :3-5% :
• •
Komoditi
• •
Sufficient gas tightness. Pasokan O2 harus dibawah kebutuhan untuk respirasi Insulation against heat loss Accurate control of the desired gas concentration. Too low O2 anaerobic respiration; too high CO2 injure fruits Good air circulation Small access door for emergency escape, sampling and inspection Memiliki vent valve Memiliki peralatan lengkap (thermometer, gas meter, light)
CONTROLLED ATMOSPHERE STORAGE (CAS)
Controlled Atmosphere Storage
CAS: O2 CO2 N2
:5% :3-5% :
Komoditi
Methods of controlling the atmosphere : • Biarkan buah melakukan respirasi untuk menghasilkan CO2 dan menurunkan O2. Ketika CO2 telah mencapai konsentrasi yang diinginkan, kondisi ini dijaga konstan. • Ketika O2 turun, inlet dibuka untuk memasukkan udara segar • Proses pemasukkan udara segar (3-4 kali/jam) memerlukan pengalaman yang cukup
MODIFIED ATMOSPHERE PACKAGING (MAP)
Environment : •T • RH •t
Packaging : • type • permeability
CO2
O2 O2
Komoditi
CO2
Respiratory rate konstan
CONTROLLED ATMOSPHERE STORAGE (CAS) for Banana
CA = O2 (2%); CO2 (7%); T (12,5 oC) 6 weeks
T (16 oC) 4 – 5 days Ripen
CA = O2 (2%); CO2 (5%); T (12,5 oC) 5 weeks
T (16 oC) 4 – 5 days Ripen
Limits of O2 for Some Commodities Table 1. O2 limits below which injury can occur for selected horticultural crops held at typical storage temperatures.
O2 (%) < 0.5 1.0
1.5 2.0
2.5 3.0 4.0 5.0 10.0 14.0
Commodities Chopped greenleaf, redleaf, Romaine and iceberg lettuce, spinach, sliced pear, broccoli, mushroom Broccoli florets, chopped butterhead lettuce, sliced apple, Brussels sprouts, cantaloupe, cucumber, crisphead lettuce, onion bulbs, apricot, avocado, banana, cherimoya, atemoya, sweet cherry, cranberry, grape, kiwifruit, litchi, nectarine, peach, plum, rambutan, sweetsop Most apples, most pears Shredded and cut carrots, artichoke, cabbage, cauliflower, celery, bell and chili pepper, sweet corn, tomato, blackberry, durian, fig, mango, olive, papaya, pineapple, pomegranate, raspberry, strawberry Shredded cabbage, blueberry Cubed or sliced cantaloupe, low permeability apples and pears, grapefruit, persimmon Sliced mushrooms Green snap beans, lemon, lime, orange Asparagus Orange sections
Data are from Beaudry (2000), Gorny (1997), Kader (1997a), Kupferman (1997), Richardson and Kupferman (1997), and Saltveit (1997). Those commodities in italics are considered having very good to excellent potential to respond to low O2.
Limits of CO2 for Some Commodities Table 2. CO2 partial pressures above which injury will occur for selected horticultural crops. CO2 (kPa) 2 3 5
7 8 10
15 20 25 30
Commodity Lettuce (crisphead), pear Artichoke, tomato Apple (most cultivars), apricot, cauliflower, cucumber, grape, nashi, olive, orange, peach (clingstone), potato, pepper (bell) Banana, bean (green snap), kiwi fruit Papaya Asparagus, Brussels sprouts, cabbage, celery, grapefruit, lemon, lime, mango, nectarine, peach (freestone), persimmon, pineapple, sweet corn Avocado, broccoli, lychee, plum, pomegranate, sweetsop Cantaloupe (muskmelon), durian, mushroom, rambutan Blackberry, blueberry, fig, raspberry, strawberry Cherimoya
Modified from Herner (1987), Kader (1997a), and Saltveit (1997).
