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Possibility to Reduce Drudgery and Time in Harvesting Individual Ripe Fruits of Jatropha curcas Linn by Whole Bunch Harvesting Silip, Jupikely James; Tambunan, Armansyah H.; Hambali, Erliza; Sutrisno, ,; Surahman, Memen
Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) Vol 38, No 2 (2010): Jurnal Agronomi Indonesia
Publisher : Bogor Agricultural University

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Abstract

<!-- /* Font Definitions */ @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-1610611985 1073750139 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin-top:0cm; margin-right:0cm; margin-bottom:10.0pt; margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman"; mso-ansi-language:IN; mso-no-proof:yes;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> A study was conducted to determine Jatropha fruits ripening uniformity on its tree and bunches characteristics. To get more information about its ripening off, the tree characteristics a respiration pattern was determined. The data were collected on fi  ve trees for each ten selected accessions (n=50) for fruit ripening uniformity on its trees study and fi  fteen bunches for each seven selected accessions (n=105) for fruits bunches ripening uniformity study at two jatropha pilot projects at Sabah state of Malaysia at the end of March 2009 when the trees were exactly one year old. This study confi  rmed that heterogeneous ripening occured in all jatropha accessions and within individual jatropha bunches. Respiration tests confi  rmed that jatropha is a climacteric fruit. The results showed an upsurge in CO2 production at the end of ripening and at the beginning of senescence. This study has  revealed indications of the possibility to harvest jatropha fruit in bunches rather than harvesting individual ripe fruit, which could potentially improve harvest effi ciency by reducing harvesting time and drudgery. Keywords: ripening, respiration rate, post-harvest, climacteric
Faktor Influencing the Vacuum Freezing Rate of Liquid Food Tambunan, Armansyah H.
Jurnal Keteknikan Pertanian Vol 14, No 3 (2000): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Many,freezing methods, mechanicul as well as cryogenic, have been in wide application in food industries. Each method has its own advantage, but in regard with the food quality, freezing rule can be accomplished by the method is one of the tnost important factors. Nowadays, many researchers are conducting experiment in order to enhance thefi.eezing rate. This paper deals with the advantage of vacuum freezing method in enhancing the freezing rate and its applicability for liquidfood.Experinrent was carried out for distilled water, milk, and fruit juice using multi-purpose vacuum equipment. As easily predicted, minimum pressure of the freezing chamber determine temperature of the product. Vuriation on the fruit juice concentration shows that faster freezing rate canbe achieved if the product is more dilute. The experiment also showed that freezing rute obtained by vacuumj-eeziirg was signijkantly faster than contact plate freezing method.
Study on Re-circulation Drying of Rough Rice Using Pneumatic Conveyor Prasetyo, Totok; Abdullah, Kamaruddin; Tambunan, Armansyah H.; Nelwan, Leopold; K.D, I Made
Forum Pasca Sarjana Vol 32, No 1 (2009): Forum Pascasarjana
Publisher : Forum Pasca Sarjana

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Abstract

Re-circulating rice dryers suitable for large amount of loading capacity.  It generally comprises of two parts, the tempering section and a drying section, and the grains are dried in an intermittent way until the final moisture content of the grains can be achieved.  Wet grains are initially dried for about 11 minutes within the drying section of the dryer.  The grains then are conveyed to the tempering section where it will be stored for about 40 to 50 minutes.  At every passes, about less than 2%(wb) of the moisture content can be removed from the grains. The number of passes required to accomplish a drying process in a recirculation dryer depends on the initial moisture content and the amount of rough rice to be dried.  The drying and tempering duration can be adjusted by means of a mechanical valve.  The purpose of this study was to examine the performance of re-circulating dryers equipped with pneumatic conveyor instead of bucket elevator to reduce electricity cost and heated using a proper blend between kerosene and jatropha oil.  Several experimental runs had been conducted under a constant drying temperature of 60oC and was controlled by adjusting the rate of fuel consumption.  The experimental results showed that the drying efficiency was in the range of 22.2% to 31.1%, the specific energy consumption was between 3.475-4.785 MJ/kg H2O evaporated, fuel consumption at 0.95 to 1.15 (liters/hr) and the drying rate was 0.9%/hr.  The entire drying operation using 465 kg of rough rice required 10 hours of drying time with 74.3% of head yield.  Mathematical model used in this study also had indicated close agreement with experimental data.   Key words: re-circulating dryer, pneumatic conveyor, drying performance, tempering period, bio-kerosene blend
Solar Drying System for Fish with Application of Trapezoidal Green House Effect Nababan, Binsar; Abdullah, Kamaruddin; Tambunan, Armansyah H.; Soepardjo, A Harsono
Forum Pasca Sarjana Vol 30, No 1 (2007): Forum Pascasarjana
Publisher : Forum Pasca Sarjana

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Abstract

Fish is a perishable product, and thereby needs a special treatment to prolong its shelf life. Traditionally, drying is a common treatment for the purpose, especially by using sun drying. This paper is devoted to the study of histiophoridae fish  drying using a truneated  trapezoidally shaped green house effect solar dryer  in order to maximize the  use of solar energy. The drying system used different size of racks and tray following the dimension of the structure so as to minimize empty space.  The dryer was   equipped with 25  watt DC blowers to remove  the moist air.  From two experimental runs, the results show that the system can properly dry the histiophoridae fish to its desired moisture content, which ranged from 30.08% (wb) to 32.80% (wb).  Utilization of the truneated  trapezoidally shaped green house effect solar dryer was found to be effective in enhancing the absorbtion of solar irradiation not only by the heat absorber but also by the producs on speated the vertically arranged racks. Solar PV modules were used to power inlet  exhaust fans as well as for temperature control. A PCM energy storage was also provided to provide heating  during night time.   Keywords: fish drying, trapezoidal shape green house, solar drying, PCM heat  storage, PV modul temperature control
The Influence of LRC Current from the Q-Meter to the Measured Value of Dielectric Properties Within Radio Frequency Range ., Harmen; Tambunan, Armansyah H.
Jurnal Keteknikan Pertanian Vol 17, No 1 (2003): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Various measurement method of dielectric properties has been studied by researches, one of wich is the Booton 160-A Q-meter operated within the radio frequency range. Determination of dielectric properties by the Q-meter is accomplised through the measurement of voltage (Q) and capacitance (C) of the LRC, which is naturally in the form of alternating current (AC). Measurement of the AC voltage by a voltmeter shows instability of the measured value, while using an osciloscope require an expensive apparatus. The problem seems can be solved by convertion of the LRC output from alternating to direct current. This paper is to study the influence of LRC output to the measured dielectric properties, by converting the output from alternating to direct current.
Design and Performance Test of Measuring Apparatus of Dielectric Properties Using Q-Meter Method Tambunan, Armansyah H.; Suyanto, Nugroho A.; Harmen, .
Jurnal Keteknikan Pertanian Vol 14, No 2 (2000): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Dielectric heating has received a lot of attention recently. Microwave heating, however, has the problem of noticeable hot and cold spots within a food. Radio frequency (RF) has the potential to overcome this problem because of its longer wavelength and greater penetration depth, which would lead to more uniform distribution of the electric field and thus a more uniform temperature distribution. The dielectric properties are the measure of a samples response to an electromagnetic field, which vary significantly with frequency, temperature, moisture, and salt content. The potential of a medium to respond to dielectric heating can be characterized by its dielectric properties, which can be strong functions of frequency and temperature. This experiment is aimed to design and test the performance of a measurement apparatus for the dielectric properties, using the Q-meter method.
Vacuum Freezing Characteristics of Passion Fruit Tambunan, Armansyah H.; Rohanah, Ainun; Purwanto, Y. Aris
Jurnal Keteknikan Pertanian Vol 17, No 1 (2003): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Pemilihan metode pembekuan merupakan salah satu aspek penting, khususnya dari sisi keteknikan. Pembandingan karakteristik pembekuan dan mutu produk yang dibekukan dengan berbagai metoda dapat digunakan untuk keperluan tersebut. Tujuan penelitian ini adalah untuk melakukan perbandingan karakteristik pembekuan antara metoda pembekuan vakum dan metoda pembekuan lempeng sentuh. Bahan yang dibekukan adalah pulp markisa. Parameter banding yang digunakan adalah profil dan sebaran suhu bahan, laju pembekuan, konsumsi energi dan parameter mutu seperti warna, kadar air, kandungan protein dan kandungan vitamin C.
Instrument Design and Measurement of Dielectric Properties Within Radio Frequency Range Harmen, .; Tambunan, Armansyah H.; Hartulistiyoso, Edy; Subrata, I Dewa Made
Jurnal Keteknikan Pertanian Vol 15, No 2 (2001): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Dielectric properties indicated the ability of a system to store, transmit anf reflect electromagnetic wave energy. Recently, the utilization of the properties in agriculture field tends tio increase. For example, dielectric drying of biological material is based on the products ability to absorb electromagnetic radiation and convert inyo heat. In addition, lower energy application of the property can be utilitized for non-destructive measurement of water content.For a more broed application, measurement of the property anf the influencing factors is indispensable.
Simulation Study on Freeze-drying Characteristics of Mashed Beef Tambunan, Armansyah H.; Solahudin, M.; Rahajeng, Estri
Jurnal Keteknikan Pertanian Vol 14, No 1 (2000): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Drying characteristic of a particular product is important in analyzing the appropriateness of the drying method for the product. This is especially important for freeze drying, which is known as the most expensive drying method, asideji-om its good drying quality. The objectives of this experiment are to develop a computer simulation program using a retreating drying-frontmodel for predicting freeze drying characteristics of mashed nteat, especially for the influence of sublimation temperature and thermal conductivity.
Study on Energy Consumption For Soybean-Sauce Production Pabrik Kecap Zebra Ciampea, Bogor Sonhaji, .; Tambunan, Armansyah H.
Jurnal Keteknikan Pertanian Vol 13, No 3 (1999): Buletin Keteknikan Pertanian
Publisher : PERTETA

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Abstract

Energy is an Important factor for the success of industrialitation. and energy consumption of an industry. especially the small and medium industry. should be optimized based on the energy efficiency system. The objective of this research is to analyse the energy consumption for soybean sauce production at Pabrik Kecap Zebra. Ciampea Bogor. and to evaluate the efficiency of stoves used at the industry.