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PENGARUH DERAJAT DEASETILASI KHITOSAN DARI KULIT UDANG TERHADAP APLIKASINYA SEBAGAI PENGAWET MAKANAN Rokhati, Nur
REAKTOR Volume 10, Nomor 2, Desember 2006
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (151.483 KB) | DOI: 10.14710/reaktor.10.2.54-58

Abstract

Industri pengolahan udang banyak menimbulkan hasil samping berupa limbah kulit udang yang belum dimanfaatkan secara optimal, yaitu hanya dijadikan tepung dan campuran makanan ternak. Hal itu kurang memiliki nilai ekonomis dibandingkan dengan mengolahnya menjadi khitin dan khitosan. Khitosan banyak digunakan di berbagai industri. Salah satu penerapan khitosan yang penting dan dibutuhkan dewasa ini adalah sebagai pengawet bahan makanan pengganti formalin. Kualitas khitosan sering dinyatakan dengan besarnya nilai derajad deasetilasi. Penelitian ini bertujuan untuk menentukan kondisi operasi optimum proses deasetilasi khitin serta mempelajari pengaruh derajat deasetilasi terhadap khitosan sebagai bahan pengawet makanan. Proses deproteinisasi dengan larutan NaOH (3.5 % w/v) selama 2 jam pada suhu 65 oC dan proses demineralisasi dalam larutan HCl (1N) selama 30 menit pada suhu kamar. Proses deasetilasi dilakukan dengan memanaskan khitin dengan larutan NaOH (20%, 30%, 40%, 50%, 60%, 70%, 80% w/v) pada suhu (50 oC, 60 oC, 70 oC, 80 oC, 90 oC, 100 oC, 110 oC) selama (1, 2, 3, 4, 5, 6, 7 jam). Parameter respon adalah derajat deasetilasi khitosan. Produk khitosan diaplikasikan untuk pengawet tahu dan analisa mikroba dilakukan dengan menggunakan metode TPC untuk mengetahui pengaruh derajat deasetilasi terhadap kemampuannya mengawetkan makanan. Hasil penelitian menunjukkan bahwa kondisi optimum proses deasetilasi khitin  menjadi khitosan adalah pada konsentrasi NaOH 50% dan suhu 100oC selama 1 jam yang memberikan derajat deasetilasi sebesar 71,2%.. Total bakteri pada perendaman tahu selama 3 hari dalam larutan asam asetat ditambah chitosan 6,8.104, dalam larutan asam asetat saja 9,9. 105, dan dalam blangko 8,6. 107, sehingga bisa disimpulkan bahwa khitosan dapat menghambat pertumbuhan bakteri. Namun meningkatnya derajad deasetilasi tidak begitu berpengaruh terhadap penurunan jumlah bakteri.
PEMBUATAN RESIN PHENOL FORMALDEHID TERHADAP APLIKASINYA SEBAGAI VERNIS Rokhati, Nur; Prasetyaningrum, Aji
REAKTOR Volume 12, Nomor 1, Juni 2008
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (144.577 KB) | DOI: 10.14710/reaktor.12.1.42-47

Abstract

Phenol formaldehid termasuk kelompok resin sintetis yang dihasilkan dari reaksi polimerisasi antara phenol dengan formaldehid. Ada dua jenis resin phenol formaldehid yaitu : novolak yang bersifat termoplast dan resol yang bersifat termoset. Phenol formaldehid dapat diaplikasikan sebagai vernis karena dapat membentuk lapisan film yang kering.Penelitian dilakukan dengan mereaksikan phenol dan formaldehid dengan pH dan perbandingan mol bervariasi. Jenis novolak dibuat pada suasana asam dengan penambahan HCl, suhu 900C, dan waktu reaksi 5 jam, sedangkan jenis resol dibuat pada suasana basa dengan penambahan NaOH, suhu 800C dan waktu reaksi 3 jam. Hasil resin phenol formaldehid diaplikasikan sebagai vernis pada kayu jati. Hasil penelitian menunjukkan bahwa dengan bertambahnya pH dan perbandingan reaktan, waktu kering semakin lama. Kondisi optimum jenis novolak diperoleh pada pH 2,5 dan perbandingan reaktan 1 : 0,8, sedangkan untuk jenis resol dicapai pada pH 10 dan perbandingan mol reaktan 1 : 2. Aplikasi jenis novolak sebagai vernis kayu menghasilkan warna yang lebih cerah (tingkat gloss tinggi) dibanding dengan jenis resol
PENGARUH COATING ALGINATE-CHITOSAN TERHADAP PERTUMBUHAN MIKROBA PADA BUAH MELON KUPASAN Cahyana, Heru; Christwardana, Marcelinus; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

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Abstract

Lack of peeling fruit processing now cause the rapid spoilage the fruit. Therefore, most of the industry slows microbial growth by using a coating on the fruit. In this study making edible films made from alginate and chitosan. Edible film also applied to peeling melon and tested the microbial growth during 3 days. The result showed melon which coating with chitosan film is very good because this film can hold up during 2 days with growth of microbe to 21,6 x 105 CFU/gr.
PENGARUH KONSENTRASI KITOSAN TERHADAP PROSES FLOKULASI PADA PEMANENAN MIKROALGA Warsita Aji, Rangga; Gusniawati, Wulan Sari; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

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Abstract

The common method used for harvesting microalgae is filtration. But, it has disadvantages such as particle size of microalgae are generally small causing the harvesting process uneffecient. It can be measure using chitosan as bioflocculant. The first procedure of research is making a stock solution of chitosan was prepared by dissolving chitosan flakes in 1% (v/v) acetic acid until the flakes was totally dissolved, then  it is introduced  into 500 ml of microalgae culture (Spirulina sp). The flocculation process is experimental designed by the variation of the concentration of chitosan (5 mg/L ; 10 mg/L ; 15 mg/L ; 40 mg/L ; 70 mg/L ; 100 mg/L) at pH 8 and slow mixing speed 40 rpm.  The result shows that increasing concentration of chitosan causes increasing flocculation efficiency but at the concentration that is too high, it will make flocculation efficiency decrease.
PENGARUH KONSENTRASI SERTA PENAMBAHAN GLISEROL TERHADAP KARAKTERISTIK FILM ALGINAT DAN KITOSAN Anward, Giovanni; Hidayat, Yusuf; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 3, Tahun 2013
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

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Abstract

Bioethanol used as fuel should have purity greater than 99.5%, but the conventional distillation produces only 95% purity. One way to increase the purity of ethanol is pervaporation method using selective membrane. The aim of this research is to prepare and characterize alginate and chitosan films. To determine the optimum concentration of alginate and chitosan films, both of these films were characterized. The results showed that the optimum alginate film obtained at 3% of concentration with the addition of 20% glycerol, while the optimum chitosan film obtained at 3% of concentration without the addition of glycerol. Alginate film has the highest permeability and swelling degree, while chitosan film has the lowest value. Alginate and chitosan films have the highest swelling degree in water, then 95% alcohol and the lowest is in PA alcohol.
PEMANFAATAN MINYAK GORENG BEKAS DAN ABU KULIT BUAH KAPUK RANDU (SODA QIE) SEBAGAI BAHAN PEMBUATAN SABUN MANDI ORGANIK BERBASIS TEKNOLOGI RAMAH LINGKUNGAN Ningrum, Naliawati Prastiya; Indra Kusuma, Muhamad Alfin; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 2, Tahun 2013
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

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Abstract

Capok Randu (Ceiba petandra (L)) Gaerin van Indica (D.C) are most everseen in Indonesia mainly as horticulture in Central Java, with the total areas of95.107,17 ha. Manufacture of capok randu’s ash leather called Soda Qie and itcontains 78%W of potassium. In the other hand, consumption of frying oil inIndonesia is very high and it increases annually, up to 500.000 tons/year. Ex fryingoil produced still contains plenty of free fatty acid and it can be used as raw materialin preparation of soap with soda qie as a source of alkaly by saponification reaction.This experiment aimed to find the optimum operation condition in soap preparationand the its reaction kinetic. This experiment is designed using RSM method (ResponseSurface Methodology) and software Statistica 6. Parameters in this research are exfrying oil volume of 100 ml, soda qie solution concentration of 300 g / 1000 ml, andsaponification reaction time of 60 minutes. Independent variables are the reaction temperature of 30, 60, 90 oC, ratio of soda qie volume : ex frying oil volume 3:1 ; 4:1; 5:1 ml. Optimation is conducted at saponification reaction time variables of 30, 60,90, 120 minutes. Observed responses are amount of Free Fatty Acid (FFA), and freealkali of the product. The optimum operation condition are gained at temperatur of90oC, reactant ratio of 3:1. In the soap product, the number of FFA are 0,80%, andthe number of free alkali are 0,08%, this is fulfill the SII.0005-72. The rate constantgained were 0,068 menit-1.
PENGARUH COATING ALGINATE-CHITOSAN TERHADAP PERTUMBUHAN MIKROBA PADA BUAH MELON KUPASAN Cahyana, Heru; Christwardana, Marcelinus; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Lack of peeling fruit processing now cause the rapid spoilage the fruit. Therefore, most of the industry slows microbial growth by using a coating on the fruit. In this study making edible films made from alginate and chitosan. Edible film also applied to peeling melon and tested the microbial growth during 3 days. The result showed melon which coating with chitosan film is very good because this film can hold up during 2 days with growth of microbe to 21,6 x 105 CFU/gr.
HIDROLISIS KITOSAN MENGGUNAKAN KATALIS ASAM KLORIDA (HCl) Adhiatama, Irsan; Zainudin, Muhamad; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

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Abstract

The molecular weight is an important factor in the application of chitosan. High molecular weight will restrict the use of chitosan. This research uses a chemical process with acid hydrolysis. Hydrolysis is de-polymerization to lower molecular weight that occur because of the termination of glycoside bond by reaction with water (H2O). De-polymerization of chitosan is different from other polysaccharide compounds, because its have a difficult decomposed β-bond and a cationic amine groups. Therefore, it required operating conditions and type of catalyst to produce chitosan in accordance with specifications. The purpose of this research is to obtain optimum conditions of chitosan hydrolysis process and determine the type of acid catalyst is best to produce chitosan with low molecular weight (LMWCs). Results showed that temperature, catalyst concentration, and type of catalyst greatly affect on the depolymerization of chitosan. Depolymerization effect increases with increasing temperature and catalyst concentration, characterized by reduced viscosity and molecular weight of chitosan. To produce chitosan with a molecular weight between 50-100 kDa, optimum conditions : temperature of 70 0C, hydrolysis time 120 minutes, and the concentration of Hidrochloric Acid (HCl )was 0.6 to 0.8 N.
DEPOLIMERISASI KITOSAN DENGAN HIDROLISA ENZIMATIK MENGGUNAKAN ENZIM α-AMILASE P.L., Hanik Handayani; R., Paramarta Siwi; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 4, Tahun 2013
Publisher : JURNAL TEKNOLOGI KIMIA DAN INDUSTRI

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Abstract

Chitosan is a polymer derivative of chitin that has many benefits in food and medical. Since chitosan has a large molecular weight, it has constraints to its application. To overcome the disadvantage, it needs hydrolysis of chitosan in order to obtained a lower molecular weight. In this research the hydrolysis of chitosan will  be operated by enzymatic process uses thermophilic enzyme α-amylase. The experiment begins by making a chitosan solution 1% w/v in an acetic acid solution 1% v/v. The chitosan solution is hydrolyzed using the enzyme α-amylase with varied pH, operating temperature, time, and ratio of the enzyme:substrate to obtain the optimum. The response comprehends Dextrose Equivalent (DE), viscosity, and the average of molecular weight. The results showed that the optimum operating conditions for chitosan hydrolysis using α-amylase enzyme is at pH 5, temperature 90 °C, 2 hours operating time, and ratio of enzyme:substrate 1:2500 (0,1 ml). For variable pH, temperature, time, and enzyme addition, DE rises meanwhile variables are increased, then it dropped significantly after the optimum level. The hydrolysis can reduce molecular weight of chitosan from 1680-1750 kDa to 144,18 kDa thus it is included to MMWCs.
KARAKTERISASI FILM KOMPOSIT ALGINAT DAN KITOSAN Rokhati, Nur; Pramudono, Bambang; Widiasa, Nyoman; Susanto, Heru
REAKTOR Volume 14, Nomor 2, Oktober 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (517.1 KB) | DOI: 10.14710/reaktor.14.2.158-164

Abstract

CHARACTERIZATION OF ALGINATE AND CHITOSAN COMPOSITE FILM. Due to the specific characteristics of (thin) films, the use of polymer films in various aplications has singnificantly increased. Alginate and chitosan are natural polymers, which have potential as a raw material for the manufacture of composite films. This paper presents the preparation and characterization of alginate, chitosan and chitosan-alginate composite films. The film characterization included permeability test, degree of swelling, mechanical property, morphology (by SEM), and surface chemistry (by FTIR). The results showed that alginate films have a higher permeability ​​and degree of swelling (DS) than chitosan films. Both permeability and DS decreased with increasing concentration for both alginate and chitosan films. DS experiments showed that the films have the highest DS in water followed by ethanol 95% and ethanol >99.9%, respectively. The mechanical strength of chitosan films was larger than alginate films. Alginate-chitosan composite films prepared by layer by layer method showed better characteristics than the composite films prepared by blending of alginate and chitosan solutions. Meningkatnya aplikasi film polimer di berbagai industri tidak terlepas dari keunggulan yang dimiliki. Alginat dan kitosan merupakan polimer alam yang mempunyai potensi sebagai bahan dasar pembuatan film komposit. Pada penelitian ini dilakukan pembuatan dan karakterisasi film komposit berbasis alginat dan kitosan. Karakterisasi film yang dilakukan meliputi uji: permeabilitas, derajat swelling, mekanik, morfologi (dengan SEM), dan struktur kimia permukaan (dengan FTIR). Hasil penelitian menunjukkan bahwa film alginat mempunyai nilai permeabilitas maupun derajat swelling yang lebih tinggi dibanding dengan film kitosan. Baik pada kitosan maupun alginat memberikan fenomena bahwa semakin besar konsentrasi larutan maka semakin kecil nilai permeabilitas maupun derajat swelling, dengan derajat swelling terhadap air adalah yang  paling besar kemudian diikuti oleh ethanol teknis (± 95%) dan yang terkecil adalah ethanol PA (> 99,9%). Kekuatan mekanik film kitosan lebih besar dibanding dengan film alginat. Film komposit alginat-kitosan yang dibuat dengan metode layer by layer memberikan karakteristik yang lebih baik dibanding dengan film komposit yang dibuat dengan pencampuran larutan alginat dan larutan kitosan.