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agriTECH
Published by Universitas Gadjah Mada
ISSN : 02160455     EISSN : 25273825     DOI : 10.22146/agritech
Core Subject : Agriculture,
Agriculture, Biological Sciences & Forestry
Agritech with registered number ISSN 0216-0455 (print) and ISSN 2527-3825 (online) is a scientific journal that publishes the results of research in the field of food and agricultural product technology, agricultural and bio-system engineering, and agroindustrial technology. This journal is published by Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta in colaboration with Indonesian Association of Food Technologies (PATPI).
Arjuna Subject : Ilmu Pertanian dan Biologi (Semua) - Ilmu Pertanian dan Biologi (Lain-Lain)
Articles 15 Documents
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Search results for , issue "Vol 32, No 3 (2012)" : 15 Documents clear
Pengaruh Suhu dan Lama Proses Sulfonasi dalam Proses Produksi Methyl Ester Sulfonic Acid (MESA) Menggunakan Single Tube Falling Film Reactor (STFR) Siti Mujdalipah; Erliza Hambali; Ani Suryani; Edi Zulchaidir
agriTECH Vol 32, No 3 (2012)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (320.642 KB) | DOI: 10.22146/agritech.9614

Abstract

Methyl Ester Sulfonic Acid (MESA) is an intermediate product of Methyl Etser Sulfonate (MES). MES has manyapplications for personal care products, washing and cleaning products, and Enhanced Oil Recovery (EOR). MESA production using SO3 in Single Tube Falling Film Reactor (STFR) is a common practice. This study was aimed to getthe best condition of methyl esters (ME) sulfonation process from palm olein using SO3 gas in STFR. The study wasdone in three stages which were production activities, analysis, and data processing. Research activities consisted ofproduction process of methyl esters from palm olein and studying of temperature and sulfonation time effects towardME sulfonation process using STFR. Analysis stage include analysis of physico chemical properties of palm olein,analysis of physico chemical properties of methyl esters, and analysis of physico chemical properties of MESA. Tostudy the effect of temperature and sulfonation time toward ME sulfonation process, temperatures of 70, 90, and 110.ABSTRAKMethyl Ester Sulfonic Acid (MESA) merupakan produk antara dari surfaktan Metil Ester Sulfonat (MES). MESmemiliki beragam aplikasi dalam produk personal care, pencuci dan pembersih, dan untuk Enhanced Oil Recovery(EOR). Proses produksi MESA menggunakan gas SO3 dalam Single Tube Falling Film Reactor (STFR) merupakanteknologi yang umum digunakan. Kajian ini bertujuan untuk mendapatkan kondisi proses sulfonasi metil ester oleinterbaik menggunakan gas SO3 dalam STFR. Kajian dilakukan dalam tiga tahap, yaitu tahap penelitian, tahap analisis,dan tahap pengolahan data. Tahap produksi MESA terdiri dari pembuatan metil ester (ME) dari olein minyak sawit dankajian pengaruh suhu dan lama proses sulfonasi. Tahap analisis meliputi analisis sifat Þ siko kimia olein minyak sawit,analisa sifat Þ siko kimia ME olein sawit, dan analisis sifat Þ siko kimia MESA olein sawit. Kajian pengaruh suhu danlama proses sulfonasi terhadap proses sulfonasi metil ester olein terdiri dari suhu 70, 90, dan 110 oC dan lama prosessulfonasi 30, 60, dan 90 menit. Analisis varian pada !=0,01 menunjukan bahwa lama proses sulfonasi berpengaruh nyataterhadap kadar bahan aktif. Analisis varian pada !=0,01 juga menunjukan bahwa lama proses sulfonasi berpengaruhnyata terhadap nilai pH, bilangan asam, bilangan iod, dan kemampuan MESA dalam menurunkan tegangan antarmuka(IFT, Interfacial Tension) antara air formasi dan minyak bumi. Proses sulfonasi terbaik dicapai pada suhu sulfonasi 90oCdan lama proses sulfonasi 90 menit. Kondisi proses sulfonasi terbaik dapat menghasilkan MESA dengan karakteristikkadar bahan aktif 31,44%, pH 2,66, bilangan asam 24,88 ml NaOH/g sampel, bilangan iod 11,95 mg I/g sampel, danmemiliki kemampuan menurunkan IFT antara air formasi dan minyak bumi dari 30 dyne/cm menjadi 3 dyne/cm.
Pemodelan Matematik Perubahan Parameter Mutu Selama Penyimpanan dan Sorpsi-Isotermi Kerupuk Goreng Pasir Siswantoro Siswantoro; Budi Rahardjo; Nursigit Bintoro; Pudji Hastuti
agriTECH Vol 32, No 3 (2012)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (438.933 KB) | DOI: 10.22146/agritech.9615

Abstract

Shelf life of food is a time limit to which consumers can still accept its product quality. Chip fries are food product that has a hygroscopic property so that easy to absorb water vapor from environment. Hygroscopic property owned by chip is interesting phenomenon to be evaluated especially related to the change of quality product parameter during storage. At this research, samples were stored at room environment (T = 28 oC, RH = 80 %). The purpose of this research is to develop mathematical model of changing quality product parameter covering moisture content, stress, and strain during storage, and to get sorption-isotherm curve from chip fries. Research was done in laboratory by using research materials such as river sand, ferric sand, chip, and saturated salt solution. Diameter of river sand were 0.25 - 2.00 mm, and ferric sand were 0.10 - 0.40 mm. Frying process was conducted at temperature of 180 – 220 oC, and used a cylindrical fryer set at 5 – 36 rpm. Equipments used in this research consisted of stress-strain measuring instrument (universal of testing machine), oven, analytical balance, frying machine, tachometer, desiccators, hygrometer, thermocouple, data logger, interface, and personal computer. Result show that, the changing of product parameter during the storage reduced quality of chip especially related to the level of crispiness. This was caused by the value of water contain, stress, and strain which increased during storage. The error of prediction values and standard deviation of the developed model was less than 10% indicating that the mathematical model developed in this study was good.ABSTRAKUmur simpan suatu produk makanan adalah suatu batas waktu kualitas produk yang masih diterima oleh konsumen.Kerupuk goreng adalah produk yang bersifat higroskopis sehingga mudah menyerap uap air dari lingkungan. Sifathigroskopis yang dimiliki kerupuk merupakan fenomena menarik untuk diteliti, khususnya yang berhubungan denganperubahan parameter mutu produk selama penyimpanan. Pada penelitian ini penyimpanan dilakukan pada udaralingkungan (T = 28 oC, RH 80 %). Tujuan dari penelitian ini adalah untuk mengembangkan model matematika tentangperubahan parameter produk meliputi kadar air, tegangan, regangan selama penyimpanan, dan mendapatkan kurvasorpsi-isotermi dari kerupuk goreng pasir. Penelitian dilakukan dengan eksperimen laboratorium menggunakan bahanpasir kali, pasir besi, kerupuk mentah, dan larutan garam jenuh. Kisaran diameter pasir kali yang digunakan adalah0,25 – 2,00 mm, dan pasir besi adalah 0,10 – 0,40 mm. Penggorengan dilakukan pada suhu 180 – 220 oC, denganputaran slinder 5 – 36 rpm. Alat yang digunakan terdiri dari alat untuk mengukur tegangan dan regangan (universaltesting machine), oven, timbangan analitik, mesin penggoreng dengan pasir, tachometer, desicator, hygrometer,thermokopel, data logger, interface, dan komputer. Dari hasil penelitian diperoleh bahwa, perubahan parameter mutuproduk selama penyimpanan akan menurunkan mutu kerupuk khususnya yang berkaitan dengan tingkat kerenyahan,karena kadar air, tegangan, dan regangangan selama penyimpanan mengalami kenaikan. Kesalahan nilai prediksi dandeviasi standard pada penggunaan model matematik untuk perubahan parameter mutu kerupuk lebih kecil dari 10%.Hasil ini mengindikasikan bahwa model matematik yang dikembangkan mempunyai nilai prediksi dengan tingkatketelitian cukup baik.
Potensi Bakteri Asam Laktat yang Diisolasi Dari Bekasam sebagai Penghasil Angiotensin Converting Enzyme Inhibitor pada Fermentasi “Bekasam-Like” Product Prima Retno Wikandari; Suparmo Suparmo; Yustinus Marsono; Endang Sutriswati Rahayu
agriTECH Vol 32, No 3 (2012)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (344.789 KB) | DOI: 10.22146/agritech.9616

Abstract

Bekasam, an traditional fermented fi sh is perceived to have antihypertensive activity, which was estimated to bethe activity of ACE inhibitory peptides, the product of proteolytic degradation of fi sh protein during the bekasamfermentation. Lactic acid bacteria was possibly to give a role on proteolytic degradation to produce ACE inhibitorpeptides in bekasam fermentation. Six strains of the selected strains of proteolytic lactid acid bacteria from bekasam,namely Lactobacillus plantarum B1765, L. plantarum T2565, L. plantarum N2352, L. plantarum B1465, Lactobacilluspentosus B2555, and Pediococcus pentosaseus B1661, were assessed for growth characteristics. The amount of peptidesas result of proteolitic degradation, and the inhibitory activities of ACE inhibitor which is released in fermentationof “bekasam-like” product. All selected strains grew well, exhibited proteolytic activity which was showed by theincreasing of peptides. The extent of proteolysis varied among strains and appeared to be time dependant. The highestpeptides (8.55 ± 0.05 mg/g sample) was found on L. plantarum B1765 and the smallest one (4.45±0.10 mg/g sample)on P. pentosaceus B1661. L. plantarum B1765 exhibited the highest ACE inhibitor activity (68.17±1.32%), followed by L. plantarum T2565 (62.54±2.11%), L. plantarum N2352 (61.56±1.32%), L. plantarum B1465 (59.85±1.58%), and L. pentosus B2555 (56.61±4.28%), whereas P. pentosaceus B1661 (18.66±3.91%) showed the smallest one.ABSTRAKBekasam adalah salah satu produk ikan fermentasi tradisional. Produk ini diduga mempunyai aktivitas antihipertensiyang disebabkan oleh aktivitas peptida Angiotensin Converting Enzyme (ACE) inhibitor yang dihasilkan dari degradasiproteolitik selama proses fermentasi bekasam. Bakteri asam laktat diduga berperan dalam degradasi proteolitikmenghasilkan peptida ACE inhibitor pada fermentasi bekasam. Sebanyak 6 strain bakteri asam laktat terpilih yangdiisolasi dari bekasam yaitu Lactobacillus plantarum B1765, L. plantarum T2565, L. plantarum N2352, L. plantarumB1465, Lactobacillus pentosus B2555, Pediococcus pentosaseus B1661 telah dikaji pertumbuhan, jumlah peptidayang terbentuk dari hasil degradasi proteolitik dan presentase penghambatannya terhadap aktivitas ACE selamafermentasi “bekasam-like” product. Semua strain dapat tumbuh dengan baik dan menunjukkan peningkatan jumlahpeptida dan peningkatan aktivitas penghambatan selama proses fermentasi yang bervariasi antar strain. Jumlah peptidatertinggi pada akhir proses fermentasi (8,55 ± 0,05 mg/g) dihasilkan L. plantarum B1765 dan terkecil (4,45±0,10mg/g) dihasilkan oleh P. pentosaceus B1661. L. plantarum B1765 juga menghasilkan aktivitas penghambatantertinggi (68,17±1,32%), diikuti oleh L. plantarum T2565 (62,54±2,11%), L. plantarum N2352 (61,56±1,32%), L.plantarum B1465 (59,85±1,58%), L. pentosus B2555 (56,61±4,28%), aktivitas penghambatan terkecil dihasilkan olehP. pentosaceus B1661 (18,66±3,91%).
Formulasi dan Stabilitas Mikroemulsi O/W sebagai Pembawa Fucoxanthin Lutfi Suhendra; Sri Rahardjo; Pudji Hastuti; Chusnul Hidayat
agriTECH Vol 32, No 3 (2012)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (231.714 KB) | DOI: 10.22146/agritech.9617

Abstract

The objective of this study was to obtain a clear and stable oil-in-water (o/w) microemulsion containing fucoxanthinwhich is intended for aqueous food system application. Virgin coconut oil (VCO) was used as the oil phase andcombination of Tween 80, Tween 20 and Span 80 were selected as nonionic surfactant having high, medium, and lowHLB (Hydrophilic-Lipophilic Balance) values, respectively. The o/w microemulsions were formulated to have the Þ nalHLB values of 13.5, 14.0, and 14.5. For each HLB value, three different microemulsion formulas were determined. Allof the formulated microemulsions were then subjected to oven heating at 105 oC for 5 hour, centrifugation at 4500 rpmfor 30 min, incubation at different pH (3.5, 4.5, and 6.5), water dilution, and photooxidation to evaluate its stability.The most stable microemulsion was then selected and used to deliver fucoxanthin as a hydrophobic antioxidant inaqueous system. Photo-oxidation was performed by exposing the microemulsions under ß uorescent light at 4,000 luxfor up to 4 hours at room temperature. Peroxide values were measured every hour using ferric thiocyanate method.Stable o/w microemulsions were obtained when its HLB value was 14.5, the ratio of oil:surfactants was 3:17, andthe ratio of (oil + surfactants) : water was 35 : 65. The ratio of Tween 80 : Tween 20 : Span 80 was 92.0 : 2.5: 5.5. Fucoxanthin microemulsion was remained stable at pH range from 3.5 to 6.5 even after heating treatment,centrifugation, and water dilution. However, there were increased peroxide values of these microemulsions after being subjected to photooxidation. The presence of fucoxanthin (over 12 ppm) in the microemulsion could not effectively inhibit photooxidation of the o/w microemulsion.ABSTRAKTujuan penelitian ini adalah untuk memperoleh mikroemulsi minyak dalam air (o/w) yang mengandung fucoxanthinyang stabil dan jernih untuk diaplikasikan dalam sistem makanan aqueous. Virgin coconut oil (VCO) digunakansebagai fase minyak dan kombinasi Tween 80, Tween 20 dan Span 80 sebagai surfaktan non ionik yang masingmasingmempunyai nilai HLB (Hydrophilic-Lipophilic Balance) tinggi, medium dan rendah. Formulasi mikroemulsio/w ditentukan nilai HLB akhir masing-masing 13,5; 14, dan 14,5. Masing-masing nilai HLB tersebut ditentukan tigaformula yang berbeda. Semua formulasi mikroemulsi kemudian dipanaskan dalam oven pada suhu 105 oC selama 5jam, disentrifugasi pada kecepatan 4500 rpm selama 30 menit, diinkubasi pada pH yang berbeda (3,5; 4,5 dan 6,5),diencerkan dengan akuades dan stabilitas diuji secara fotooksidasi. Mikroemulsi paling stabil selanjutnya dipilih dandigunakan untuk pembawa fucoxanthin sebagai antioksidan hidrofobik dalam sistem aqueous. Fotooksidasi ditentukandengan menempatkan mikroemulasi di bawah sinar ß ouresensi 4000 lux selama 4 jam pada suhu ruang. Angkaperoksida diukur setiap jam menggunakan metode feri thiosianat. Mikroemulsi o/w yang stabil diperoleh pada HLB14,5 dengan rasio minyak : surfaktan = 3 : 17 dan rasio minyak + surfaktan : air = 35 : 65. Rasio Tween 80 : Tween 20: Span 80 adalah 92.0 : 2.5 : 5.5. Mikroemulsi fucoxanthin yang diperoleh stabil pada pH 3,5 sampai 6,5 dan bahkansetelah perlakuan pemanasan, sentrifugasi dan pengenceran. Namun angka peroksida meningkat selama fotooksidasi.Fucoxanthin dalam mikroemulasi lebih dari 12 ppm tidak efektif untuk menghambat fotooksidasi dalam mikroemulsio/w. 
Aktivitas Antioksidan Berbagai Fraksi dan Ekstrak Metanolik Daun Beluntas (Pluchea indica Less) Paini Sri Widyati; Hanny Wijaya; Peni Harjosworo; Dondin Sajuthi
agriTECH Vol 32, No 3 (2012)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (215.981 KB) | DOI: 10.22146/agritech.9618

Abstract

This study has been done to investigate the antioxidant activity of various fractions and methanolic extract of beluntasleaves by using several test system, such as DPPH, superoxide and hydroxyl radical-scavenging activities, hydrogenperoxide scavenging activity, ferric reducing power, iron and haemoglobin chelating capacities and b-carotene–linoleicbleaching assay. The results showed that methanolic extract of beluntas leaves (EMB) and its fractions (ethyl acetatefraction (FEA), water fraction (FA) and n-butanol fraction (FNB)) had scavenging activity of DPPH radical. EMBwhich had highest phenolic content and the strongest ferric reducing power, exhibited b-carotene–linoleic bleachinginhibition and the highest superoxide scavenging activity, while FEA showed antioxidant activity based on superoxideradical-scavenging activity, iron and haemoglobin chelating capacities and ferric reducing power.ABSTRAKPenelitian ini dilakukan untuk mengetahui aktivitas antioksidan berbagai fraksi dan ekstrak metanolik daun beluntasdengan berbagai sistem uji, seperti aktivitas menangkap radikal DPPH, superoksida, hidroksil dan hidrogen peroksida,mereduksi ion besi, mengkelat ion besi dan hemoglobin (Hb) dan menghambat pemucatan asam linoleat-b-karoten.Hasil menunjukkan bahwa ekstrak metanolik daun beluntas (EMB) dan fraksi-fraksinya (etil asetat (FEA), air (FA)dan n-butanol (FNB)) berpotensi menangkap radikal bebas DPPH. EMB mempunyai kadar fenolik total dan kekuatanreduksi tertinggi lebih berpotensi menangkap radikal superoksida, mereduksi ion besi dan menghambat pemucatanasam linoleat-b-karoten, sedangkan fraksi etil asetat (FEA) mempunyai aktivitas antioksidan berdasarkan kemampuanmenangkap radikal superoksida, mereduksi ion besi, mengkelat ion besi dan hemoglobin.

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