JURNAL lSSN 2088- 6497
Agrotekno
Volume 16
Nomor 2
Agustus 2011
N.L. Ari Yusasrini Am bar Rukmini Ina Pergiati Kadek Dwi Yuliani I Ketut Suter Badrut Taman
9
JURNAL
Agrotekno
Majalah llmiah Teknologi Pertanian
Volume 16, Nomor 2, Agustus 20 II ISSN : 2088-6497
DAFTAR lSI
Regenerast Minyak Goreng Bekas dengan Menggunakan Adsorben Dari Am pas dan Daun Tebu
Penggunaan Pewama AI ami dari Ekstrak Buah Naga Merah dan Umbt Btt Pada Pembuatan Kue Ku
Yohanes Setiyo
Sumiyati 16 Optimast Ststim Pengomposan Sampah Organik Secara Open Windrow
Sri Mulyani Lutfi Suhendra 22
Ari Prihantini Gede Arda B. Rahardjo 27 Nursigit Bintoro
Formulasi Minuman Sinom dan Sinergisme Aktivitas Antioksidannya
Respiration Rate and Respiratory Quotient of Harvested ../' Oyster Mushrooms at Different Storage Temperatures
Rudiati Evi Masithoh 34 Segmentasi Ganda Pengolahan Citra untuk Menentukan Nanda Mayang Kusuma Luas Browning pada Pisang
A.A. lstri Sri Wiadnyani 39 Oksidasi Pati Kasava dengan H202 dan Asidifikasi dengan Asam Laktat untuk Meningkatkan Pengembangan pada Baking
I W. Amata Lutfi Suhendra 48 Bam bang A. H.
Pengaruh Cahaya dan Panas Terhadap Kerusakan Aktivitas Antioksidan Bubuk Simplesia Rim pang Jahe
Pclindung ProfDr.lr. GP. Ganda Putra, MP
Pcmimpin Rcdaksi Dr. Sumiyat1, S.TP., MP
Pcnelaah Prof Dr. lr. I Ketut Suter, M.S.
Prof Dr. lng. Made Merta, DAA ProfDr.lr. Made Sug1tha, M.Sc Prof Dr. lr. M. Supartha Utama, MS
Prof Dr. lr. Bam bang A H., MP Prof Dr. lr. I Ketut Satriawan, MT Prof lr. I Nyoman Semadi Antara, MP., Ph.D.
lr. I Made Anom Sutrisna W, M.App.Sc, Ph.D Dr. lr. Ni Made Wartini, MP Dr. lr. Wayan Widia, MSIE.
Dr. Ir. PK. Diah Kencana, MS.
lr. 18. Wayan Gunam, MP, Ph.D Dr. Ir. N. Kencana Putra, MP
Dr.lr. Yohanes Setiyo, MP.
lr. AAPA. Suryawan Wiranatha, M.Sc, Ph.D.
Penclaah Tamu Prof Dr. lr. Eriyatno, M.Sc.
Prof Bibek Ray, Ph.D.
Prof lr. Hari Purnomo, M.App.Sc., Ph.D.
Rcdaksi Pclaksana
Ketua · AA. Md Dewi Anggreni, S.TP.,MP.
Anggota: Ni Nyoman Sulastri, S.TP, M.Agr.
I Wayan Arnata, S.TP, M.Si.
I Wayan Rai Widarta, S.TP.,M.Si.
AA. lstri Sri Wiadnyani, S TP., M.Sc.
Produksi dan Distribusi I Nyoman Mahartajaya, S.Sos.
Ni Nyornan Ayu Rusmini, S.Sos.
lAM. Dwigandawati Pencrbit Fakultas Teknologi Pertanian
Universitas Udayana
iii -Agrotekno Vol16, Nomor 2, Agustus 2011
P
embaca yang terhorrnat, sejarah Jumal Agrotekno berawal dari tahun 1997 dengan nama Jumal Gitayana sampai dengan tahun 1999 dengan ISSN 0853-6414 Pada tahun 2000, berubah nama menjadi Jumal Agrotekno, namun masih dengan ISSN yang sama. Selanjutnya pada 20 Juni 2011, Agrotekno memperoleh ISSN baru.yaitu · 2088-6497
Pada edisi kedua d1 tahun 20 II ini Jurnal Agrotekno menyaJ ikan 8 artikel dengan beragam bahasan yang disarikan dari hasil-hasil penelitian dalam bidang pangan dan non-pangan.
Dari 8 artikel yang d1muat, satu tuhsan mengkaji Regenerasi Minyak Goreng Bekas, satu tuhsan tentang Penggunaan Pewarna Alami Dari Ekstrak Buah Naga Merah Dan Umbi Bit, dan satu artikel lainnya berisi kajian tentang Optimasi Sistim Pengomposan Sampah Organik Satu artikel menyajikan Formulas! Minuman Sinom Dan Sinergisme Aktivitas Antioksidannya. Disamping itu, ada satu artikel yang terkait dengan Respiration Rate And Respiratory Quotient Of Harvested Oyster Mushrooms, satu artikel Segmentasi Ganda Pengolahan Citra untuk Menentukan Luas Browning dan satu artikel tentang Oksidasi Pati Kasava Dengan H202 Dan Asidifikasi Dengan Asam Laktat Untuk Meningkatkan Pengernbangan Pada Baking, serta satu artikel tentang Pengaruh Cahaya Dan Panas Terhadap Kerusakan Aktivitas Antioksidan Bubuk Sirnplesia Rim pang Jahe.
Redaksi rnenyampaikan terima kasih kepada sernua pihak yang terlibat dalam penyiapan jumal ini, kepada dewan penelaah, terutama kepada penelaah tamu. Ucapan yang sama disampaikan kepada para kontributor atas surnbang--annya sehinggajumal ini dapat diterbitkan.
Selamat membaca.
Rcdaksi
AGROTEKNO 6 {2) ISSN : 2088-6497
RESPIRATION RATE AND RESPIRATORY QUOTIENT OF HARVESTED OYS- TER MUSHROOMS AT DIFFERENT STORAGE TEMPERATURES
Gede Arda', B. Rabardjo1 and Nursigit Bintoro1
1 Department Agricultural Engineering
Faculty of Agricultural Technology, Udayana University Bali, Indonesia
2Department of Food and Agricultural Engineering
Faculty of Agricultural Technology, University of Gadjah Mada, Yogyakarta, Indonesia
---ABSTRACT--- Temperature management on post- harvest handling of fruits and vegetables has an important role to preserve the product to prolong their sales appeal period or shelf life.
Besides, availability of gases around the prod- uct influences the product behavior also. The important aspects of the related-physiological behaviors are respiration rate and respiratory quotient. Those provide the initial informa- tion about the changes of gas composition in inner space of storage jar as well as the sign of the shift of aerobic to anaerobic respiration occurred. Based on that issue, the aim of this work is to study the physiological behaviors of Oyster mushroom on various temperature storage and gas concentration. The object of study was Oyster mushrooms (Pieurotus os- treatus) produced by the local farmers. Respi- ration rate was determined by closed or static system until gas composition shows 1-2% of 02 and 20-21% of C02 under 5"C, l5"C and ambient storage temperature.
The result showed that respiration rate of Oyster mushroom was influenced by stor- age temperature with activation energies of 2.33 kJ/mol and 2.08 kJ/mol for 02 consump- tion and C02 evolution respectively. Respi- ration rates resulted from this measurement were 55.45 ml02/kg.h, 135.97 ml02/kg.h, 318.97 ml02/kg.h and 61.59 miC02/kg h, 165.34 miC021kg h, 335.76 mlC02/kg h for 5"C, l5"C and ambient storage temperatures respectively. In this work also was found that
Oyster mushrooms were not C02 sensitive (tolerant of high C02 concentration). The value of respiratory quotients were not much different although the concentrations of C02 reach more than 15 %. Respiratory quotient of mushroom under 5"C, 15"C and ambient storage tempera- tures were 1.11, 1.22 and 1.05 respectively.
Keywords : Oyster mushroom. Pleurotus ostrea- tus. respiration rate. respiratory quotient. activa- tion energy.
INTRODUCTION
Some agricultural produces are perishable that characterized by their short shelf life. Physical, chemical or biological damages on product accelerate the deteriora- tion of products. The improper management of storage conditions, i.e., too warm or too cold for a certain product, is another factor that in creases physiological deterioration. The shelf life of certain products could be extended by applying the proper packaging system also.
Temperature and humidity were essential fac- tors for fresh products shelf-life-extension- efforts. Respiration rate which indicates many metabolic activities of the tissues as well as the rate of quality degradation of stored prod- ucts could be suppressed through lowering
Respiration rate Respiratory Quotient of Han-ested Oyster Mushrooms at Different Storage Temperatures
the storage temperature to slightly above the critical temperature of certain product (Saltveit.
2004 ). The second factor that has great influence on product quality is humidity. Weight loss can be controlled by reducing the gradient of water vapor pressure (WVP) between product's sur- face and surrounding atmosphere (Perkins et al, 2008). Losing 1-2 %of water of produce can reduce sales appeal of produce of fresh produce (Kader, 2002). Therefore, the packaging system that can maintain the oxygen and carbon dioxide at certain concentration as well as humidity is needed. The characteristics of packaging system have strong relationship with characteristics of packed product. It has been proved that every product has their own unique properties; there- fore, designing of packaging system should be based on those properties. The initial knowledge that is important on designing packaging system is respiration rate on different temperature stor- age. Respiration rate is main factor that changes the composition of atmosphere dynamically on jar's head space. The gases concentration inside jar's head space is always changing dynamically until the equilibrium condition is obtained. This equilibrium condition reached when the respi- ration rate, transfer of gas oxygen and carbon dioxide were equal. Oxygen that consumed by packed products was compensated by oxygen permeating from the surrounding atmosphere.
In the same way to oxygen, the carbon dioxide which diffuses to surrounding atmosphere is re- placed by diffusion from product's tissues. On one hand, oxygen must be available for respira- tion to avoid anaerobic respiration during stor- age. On the other hand, over supply of oxygen makes the packaging has no benefit for prolong- ing shelf life. The critical threshold of gas con- centration is considered to design the magnitude of gas transferofpackaging film (Beaudry et aL 1992).
The water vapor that produced from
28-Agrotekno Vol16, Nomor 2, Agustus 2011
respiration and transpiration continuously adds the water vapor contained in jar's head space.
Water vapor diffuses to ambient environment with a certain magnitude. Most of them con- dense on product's or packaging's surface when saturated water vapor pressure at certain tem- perature is exceeded. This liquid water encour- ages the microbial development and reduces the diffusivity of packaging film.
Mushroom is one of the vegetables that have short shelf life, only 3 days on ambi- ent temperature (Czapski and Szudyga, 2000).
Their dermal tissues have no cuticle to protect them from physical damages or microbial at- tack or water loss (Martine et al., 2000). High moisture content in their fruit body's makes mushrooms respire and transpire with high rate.
Mushroom need low temperature storage (0 - 2"C), low 02 concentration and relatively high C02 concentration as well as high humidity (90- 98%) (Thompson et al, 2002).
Oyster Mushroom (Pieurotus ostreatus) becomes commercial product that is highly de- manded nowadays in Yogyakarta. Local farmer and seller pack the mushroom with commercial plastic bag which was available on traditional market. It was needed physiological properties data of Oyster mushroom, that were still rare, to choice the right kind of bag plastic or to design the proper packaging system. Therefore, the aim of this work is to study the physiological behav- iors of Oyster mushroom on several variations of temperature storage and gas concentration.
THEORETICAL APPROACH Respiration
Respiration is the oxidative break- down of complex substrate normally present in plant cells -such as starch, sugars, and or- ganic acids- to simpler molecules such as C02 and H20. Concomitant with this catabolic
reac tion is the production of energy and inter- mediate molecules that are required to sustain the myriad of anabolic reactions essential for the maintenance of cellular organization and membrane integrity of living cells (Kader and Saltveit, 2003 ). Oxygen which is needed for oxi- dation must be available in the course of respi- ration process. Respiration on fresh produce lo- cated on free atmosphere can be considered that availability of oxygen is unlimited, therefore availability of oxygen does not inhibits the res- piration. Otherwise, limitation of oxygen availa- bility on surrounding atmosphere suppresses the rate of respiration (Kader and Saltveit, 2003).
Depletion of oxygen and accumulation of car- bon dioxide inhibit the reaction on internal tis- sue. Respiration is enzymatic reaction that has common characteristic such as depend on sub- strate concentration, pH, and temperature and of course the concentration of enzyme that cataly- ses the reaction (Metzler, 2002 ). Enzyme needs pH range 5.5 to 7.5 to perform optimum activity on reaction. Besides, enzyme needs optimum reaction temperature also (Kader and Saltveit, 2003 ). Enzyme can be inactivated if the reaction temperature very low otherwise enzyme will be denaturalized on too high reaction temperature (Belitz, Grosch, Schiberle, 2009). So, three fac- tors that influence the activity of enzyme are substrates concentration, pH and reaction tem- perature. Heat is released during respiration, 686 kcal or 2870 kJ heat is released per I mole of glucose. Besides, 0.8-1 fraction of heat released is used to heat the surrounding atmosphere or to increase temperature of product (Ooraikul and Stiles, 1991).
Respiratory quotient
Respiratory quotient is defined as ra- tio of production rate of C02 to consumption rate of 02. According to respiration equa- tion in which mole 02 consumed is equal to mole of C02 produced indicated by coeffi- cient of every species that involve in reaction.
Cede Arda. B. Rahardjo and Nursigit Bintoro
C6 Hl2 06+602-+6C02+6H20+heat (Oorai- kul and Stiles, 1991 ).
From the definition it can be concluded that the respiratory quotient is preferable to evaluate the respiration. Increasing on magnitude of respira- tory quotient indicates respiration is approach- ing to anaerobic respiration or production rate of C02 is higher than consumption rate of 02.
Kader(2002) suggested that respiratory quotient on aerobic respiration range between 0.8 to 1.3 and the exact value is depending on the intrinsic properties of product and the storage condition.
METHOD
Sample preparation
Oyster mushroom was obtained from UD. Agro Mandiri Yogyakarta located on Pa- kem Village. It took about 45 minutes travelled by motorcycle. Mushrooms were harvested ear- ly in the morning, it was about 5 o'clock, and then the harvested mushrooms were spread on the floor covered by paper to reduce the water which covers the mushroom's surface. Mush- rooms were weighted before packed into box.
Mushroom then transported to Operation Unit Laboratory of Agricultural Technology Faculty of Gadjah Mada University. The last step was storing the mushrooms at 5"C or 15"C for I hour to equilibrate the mushroom's temperature ac- cording to treatment temperature.
Three replications were prepared to in- vestigate the respiration rate on different storage temperatures. The plastic jars 9 liters were used on this work. Two holes were made on the lid of plastic jars to facilitate the measurement of gas concentration.
Respiration rate measurement
Mushrooms were weighted range from 300 to 500 grams according to storage tempera- ture and then were placed in 9 liters plastic jars.
Paraffin wax was used to cover the gap between the lid and the body of the jar as well as at the hole at its lid. The mass of mushroom used were
±500 grams, ± 400 grams and ±300 grams for SoC, I SoC and room temperature respectively.
llllllliiL'
Respiration rate Respiratory Quotient of Han-es ted Oyster Mushrooms at Different Storage Temperatures
Those masses differences were intentionally used for avoiding small gas concentration change on measurement-time-range in which was diffi- cult to measure due to lack of accuracy of in- struments. Gas compositions were measured by Cosmotector XP-314 type (Sensorex Oy, Fin- land) for Oxygen concentration and Cosmotec- tor XP-318 type (Sensorex Oy, Finland) for C02 concentration. The instruments have an accuracy of 0.1%. Gas composition measurements were taken every 4 hours, 3 hours and 2 hours for 5"C, 15"C and room temperature respectively, until 1-2% oxygen level was obtained.
RESULTS AND DISCUSSION
Respiration rate
Respiration rate measured in this work was not daily respiration development of har- vested mushrooms but respiration rate at dif- ferent gas composition. The gas composition change occurred when oxygen was consumed and carbon dioxide was produced by product.
The mushroom stored without interruption and measurements were periodically conducted dur- ing storage. Each data point in the figures below was taken to be initial gas composition for the next measurement.
Amount of measurement data indi- cated the rate of gas composition change in- side the jar's head space. Amount of meas- urement data time by period of measurement showed the spending time for the head space to obtain 1% oxygen or 20% carbon dioxide level. The lowest storage temperature, 5 OC, spent 52 hours to obtain those levels. This pe- riod was longer than period that mushrooms spent at 15"C with 18 hours and 14 hours at room temperature. Crossing point between 02 and C02 curves occur at near I 0% level.
30-Agrotekno Vol16, Nomor 2, Agustus 2011
This indicates that mushrooms spend equal time to obtain the half level of head space concentration and also indicates that the ratio between 02 consumption rate and C02 pro-
duction rate approaches I.
~~---~
-;:-20
~ ~ .~ 15
-e :lD
u 5
o-~~~-..~-.-~--,-~-,-~~
0 1 2 3 4 S S 7 8 9 WU Ull M n"data
Figure I. Gas concentration development at SOC (data are taken every 4 hours)
~ ~---~
20
i
g 1§~ E
ilO
5
0 ~
0 2 3 4 5 s 7
n111dilta
Figure 2. Gas concentration development at 15"C (data are taken every 3 hours)
Z~---~
~20
~
s15
~ Elll
g
8 5
0~~--~--r--T--~~r-~~
0 1 2 3 4 5 s 7 8
.... data
Figure 3. Gas concentration development at room temperature (data are taken every 2 hours)
Figure 1-3 show that rapid respiration oc- curs at initial storage of mushrooms. Abundant oxygen on head space and field heat that still re- main accelerate the respiration. Respiration con- tinuously decreases when oxygen is getting thin- ner and carbon dioxide getting thicker as well as product temperature getting colder. Oyster mush- room respires rapidly faster than 60 ml 02/hr.kg, therefore mushroom Oyster is grouped in vegeta- bles with very high respiration rate(Kader, 2002) Respiration and temperature
Data demonstrate that temperature had major influence on Oyster mushroom respiration rate. Air temperature is the most important vari- able because it tends to control flesh temperature of perishable commodities (Thompson, 2002).
Lowering temperature to ISOC and S"C could suppress the consumption rate of 02 76.4% and 95%, respectively. Slight different effect occurred to production rate of C02. Lowering temperature to I SOC and
s•c
suppressed the production rate of C02 50.7% and 81.7%, respectively. On the other hand, gas composition has minor effects on Oyster mushroom respiration i.e, at room tem- perature respiration rate decreases to 27. 9%. All of this value was calculated from the data taken at first measurement of gas concentration. First measurement was considered indicate the influ- ence of temperature alone. It was different to next measurement which was considered indicate the influence of temperature and gas concentration.This value is as great as respiration of broccoli.
Relative to held in the ambient air, the reduction in respiration rate is about 28% for broccoli heads in 2% 02 (Kader and Saltveit, 2003).
Gede Arda. B. Rahardjo and Nursigit Bintoro
Table !.Respiration rate on
s·c,
15"C and room temperature storage-
,'f .Jt co; R £R ,_
.!U .f.< I! E_:J E£ • UJ ilili ;b !_. \(OJ
...
Table. 2 Respiration rate at different 02 con- centration
Columns of Table.2 showed the influence of 02 concentration changes. But, combination of temperature and gas concentration changes gives the great influence on mushroom respi- ration.
Respiratory quotient (RQ)
Respiratory quotient could be define as the rate ratio of C02 production to 02 con- sumption; C02 and 02 could be measured in moles or volumes depending on the substrate being oxidized. RQ values for fresh commod- ities range from 0.7 to 1.3 for aerobic respi- ration. When carbohydrates are being aerobi- cally oxidized, the RQ is near l, while it is< l for lipids, and > I for organic acids. Very high RQ values usually indicate anaerobic respira- tion in those tissues that produce ethanol. In such tissues, a rapid change in the RQ could
be used as an indication of the shift
Respiration rate Respiratory Quotient of Harvested Oyster Mushrooms at Different Storage Temperatures
from aerobic to anaerobic respiration (Salt- veit, 2004). The value of the RQ presented in Table I. Although has the various value at different temperature, but the deviations is small. Those values were calculated from initial respiration where the surrounding at- mosphere was still rich in 02. Kader (2002) and Saltveit (2004) suggest that aerobically respiration on fresh produces stored at physi- ological temperature range from 0.7 - 1.3.
Therefore, those values indicate that respira- tion was aerobic. This conditions continuous- ly changes according to 02 changes, but was still in the aerobically respiration range (Ta- ble 3). Give more attentions on value on
soc
and IS"C, they show that Oyster mushrooms was not sensitive to 02 low level or C02 high level. Kader (2002) suggest that mushrooms are one of vegetables that respire highly but withstand to high level of C02. Evaluation on mushroom appearance that are stored at
soc
and packed with plastic jar for 3 days give the prove that they can preserve with low temper- ature and low 02 concentration. The exces- sive accumulation of C02 (> 12%) inside the package can cause physiological injuries to the produce, which in the case of mushrooms, results in severe browning (Nichols and Ham- mond, 1973; Lopez-Briones et al., 1992) is not proven in this case .. But authors suggest that this fact need to be investigated further, because this research is not intended to prove or to refuse that fact. Especially, the similar influences occur on different species and dif- ferent storage conditions.
Activation energy of respiration
Activation energy of respiration used to predict the respiration rate on other storage temperatures. Predictions of the respiration rate of mushroom on different storage tem- perature are conducted by taking the SOC as reference temperature. From figure below we
32-Agrotekno Voll6, Nomor 2, Agustus 2011
can see that the influence of temperature has linear pattern. The gradient of each linear equations come from linearization represents the activation energy and universal gas con- stant ratio (Ea/R).
Table 3. Respiratory quotient on different temperature and 02 composition*
1.19 0.61 1 l l
o.~J 0.4S 1.~
0.&7 J.3S 0.~-:
1..29 1.49
.,..,
0.59 1.25 0...,
O.S5 0.9<0
103 1.23 1.04 1.06 1.01 1.03
*The 02 concentrations refers to Table 2 Applying the Arrhenius' law, respiration rate of mushrooms along physiological tempera- ture can be counted.
In ff~
=
0.28(f.:-- i:. ) ...
(a)In
1W, =
0.25 ( ~. - ~' ) ... (b) Where subscript on parameter RR and T rep- resent value of respiration rate on storage temperature Tat condition I (reference) and storage temperature T will be found. Equa- tions (a) and (b) are the predictive equation for 02 consumption and C02 production rate, respectively. With the activation energy (Ea) are 2.33 kJ/mol and 2.08 kJ/mol for 02 consumption and C02 evolution respectively, prediction of respiration rate of Mushroom Oyster atsoc
to 300C is easy to count. This Arrhenius equation assists the engineer to de- sign of packaging system.CONCLUSIONS
The important physiological aspects of postharvest handling of fruits and vegetables are physiological behaviors including respiration rate and respiratory quotient. Oyster mushrooms show the significant influence of temperature on its respiration but less dependent on atmospheri- cally gas composition. Combination of low tem- perature and low oxygen give the great effects to mushroom respiration and less effect on respira- tory changes. Predictions of the respiration rate of mushrooms can be established satisfYingly by applying the Arrhenius equations.
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Kader, A.A and Michael E. Saltveit. Respi ration and Gas Exchange. In Postharvest Physiology and Pathology of Vegetables, 2nd edition. Marcel Dekker. Inc. New York.
Kader, A.A. 2002. Postharvest Technology of Horticultural Crops. Third Edition. Regent of University of California, Divison of Agri- culture and Natural Resources. Publication 3311 USA
Lopez-Briones, G., Varoquaux, P., C. Yves, B.
1., Bureau. G. and Pascal, B. 1992. Storage of common mushroom under controlled at- mospheres. Int. J. Food Sci.Tech
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Mikal E. Saltveit. 2004. Respiratory Metabo lism. In The Commercial Storage of Fruits, vegetables, florist and Nursery Stocks. http://
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Nichols, R. and Hammond, J.B.W 1973. Stor age of mushrooms in pre-packs: the effect of changes in carbon dioxide and oxygen on quality. J. Food Sci. Agric. 24: 1371-1381.
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