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Optimasi Pengambilan Antosianin dari Kulit Buah Naga Merah (Hylocereus polyrhizus) Sebagai Pewarna Alami pada Makanan Harjanti, Ratna Sri
CHEMICA: Jurnal Teknik Kimia Vol 3, No 2 (2016): Desember 2016
Publisher : Universitas Ahmad Dahlan

The addition of synthetic colors in foods in an attempt to attract the attention of consumers, not a ban, but if the dye used is a dye that is unusual for the food, it is harmful to health. One source of natural pigments that can be used is the red dragon fruit skin. These skins contain anthocyanins potential as a dye.Â Â Â Â Â Â Â Â Â Â Â Â In this reasearch, the observed red dragon fruit skin moisture content and size of the powder. It also conducted a stirring speed variation during the extraction process. While variable temperature, time, and solvent refers to the optimum conditions of research that has been done. Analysis of the results was conducted to determine pH, anthocyanin concentration and yield results.Â Â Â Â Â Â Â Â Â Â Â Â Based on the results obtained, the smaller the water content contained in the skin, giving absorbance values are higher. This shows that extractable anthocyanins levels are also higher. The lowest levels of the skin can be achieved in this study was 6%. The smaller the grain size, the higher the anthocyanin content. The smallest grain size achieved was 100 mesh. The highest mixing speed in this study was 300 rpm, the higher the stirring speed, the higher the anthocyanin content fetched.Â Â Â Â Â Â Â Â Â Â Â Â Organoleptic tests were conducted to study the effect of anthocyanins on the quality of the food shows that the addition of anthocyanins provide the appropriate color and do not significantly affect flavor and aroma. So it can be used as a natural dye for food.

Pupuk Organik dari Limbah Pabrik Gula Madukismo dengan Starter Mikrobia Pengurai Untuk Menambah Kandungan N, P, K Harjanti, Ratna Sri
CHEMICA: Jurnal Teknik Kimia Vol 4, No 1 (2017): Juni 2017
Publisher : Universitas Ahmad Dahlan

AbstrakÂ Blotong is sugar mill waste slude in the form of dark, often dumped, causing pollution and odor. Blotong produce about 3,8 % of cane milled by a sugar factory unit. While vinasse is waste water generated from the process of making alcohol. In the process of making one liter of alcohol will produce as much as 13 liters of vinasse. Vinasse contain many elements K, while blotong contains a lot of elements of N, P, dan Ca. This allows for composting blotong with the addition of vinasse to produce organis fertilizer. Blotong and vinasse may be seen in the PG Madukismo.Organic fertilizer through composting mixture of blotong and vinasse using microbial starter EM-4 and X-Compost can be done easily in the home environment. To determine the optimum process conditions to produce organic fertilizer, need to be varied ratio of blotong and vinasse. Composting reaction carried out for thirty days with observed in temperature and pH. Further analysis of N, P, K and C/N ratio.Based on the results obtained, the use of starter microbes X compost more prospective than using starter microbes EM-4. The compost produced by the starter microbes X-compost contains N, P, K which is much higher than the compost produced by the starter micobes EM-4. As for the addition of vinasse, will give optimum results in the addition of vinasse 25% of the weigth of blotong.Â Keywords: blotong, vinasse, compost, microbe

Biodiesel dari Limbah Pabrik Gula dan Minyak Jarak Pagar (Jatropha curcas) dengan Katalisator Zeolit Alam Klinoptilolite Harjanti, Ratna Sri; Rahmanta, Anugrah Perdana
CHEMICA: Jurnal Teknik Kimia Vol 2, No 2 (2015): Desember 2015
Publisher : Universitas Ahmad Dahlan

The fuel price increase with the increase of the number of transportation due to the increasing numbers of the population. Indonesia with more than 200 million people in need of transportation fuels in the form of gasoline and diesel in large quantities. Currently the main source of transportation fuels derived from petroleum. Premium production in Indonesia is about 62 million barrels and production of about 87 million barrels of diesel fuel. The product does not include the use for other needs, such as lubricating oil, kerosene, avgas, as well as other materials. This is particularly worrying given the oil reserves are dwindling. One of the alternative energy for transportation fuels is biodiesel as a substitute for diesel fuel.The castor oil has potential to be used as biodiesel. Fusel oil is a sugar mill waste containing alcohol. The reaction between castor oil and fusel oil with natural zeolite catalyst klinoptilolite be referred to as alcoholysis reactions that produce esters. Castor oil and fusel oil mixed with zeolite powder klinoptilolite that previously had been heated in a separate place until it reached its boiling temperature. Three neck flask fitted with a thermometer, hoses trailer makers, heater, and the agitator on 100 rpm with 100 oC of temperature. Snapshot taken at intervals of 30 minutes each. Conversion reaction calculated by analyzing the levels of glycerol bottom layer by means asetin. Alcoholysis fusel oil and castor oil with natural zeolite catalyst klinoptilolite produce esters that are approaching the properties of diesel oil with a calorific value of 19 119 Btu/lb. Optimum conversion of 57 % was obtained in alcohol - oil ratio of 9.29 mgek/mgek and the addition of a catalyst as much as 2.56% of the weight of oil.

Pemanfaatan Zeolit Alam Klinoptilolite Sebagai Katalisator dalam Alkoholisis Minyak Jarak Ratna Sri Harjanti
Jurnal Rekayasa Proses Vol 2, No 1 (2008)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Penggunaan katalisator padat pada proses alkoholisis diharapkan dapat meningkatkan kemurnian ester karena katalis padat lebih mudah dipisahkan dari pada katalis cair. Salah satu jenis katalisator padat adalah zeolit alam klinoptilolite. Dengan pertimbangan kemudahan dalam pemisahan sisa katalis dari ester yang terbentuk, maka di lakukan penelitian tentang alkoholisis minyak jarak dengan katalisator zeolit klinoptilolite dalam autoklaf. Minyak jarak, etanol, dan serbuk zeolit klinoptilolite dimasukkan ke dalam autoklaf yang dilengkapi dengan manometer, termometer, kran pengambil cuplikan, dan pemanas, kemudian autoklaf diputar. Cuplikan diambil pada setiap selang waktu 10 menit. Konversi reaksi dicari dengan menganalisa kadar gliserol lapisan bawah dengan cara asetin. Reaksi dilakukan pada suhu 120°C dan pada kecepatan putaran autoklaf 110 rpm dengan variasi prosentase katalisator dan perbandingan ekivalen etanol-minyak. Pembentukan ester diawali dengan pengaktifan etanol oleh zeolit membentuk senyawa alkoxide. Alkoxide inilah yang akan menyerang gugus karbonil pada trigiserid minyak jarak, sehingga terbentuk ester. Zeolit klinoptilolite dapat digunakan sebagai katalisator reaksi alkoholisis dengan kondisi proses yang relatif baik dijumpai pada prosentase katalisator 2,56% dan perbandingan ekivalen etanol-minyak 12,55 mgek/mgek. Pada keadaan ini konversi gliserid mencapai 73%. Kata kunci: alkoholisis, klinoptilolite, minyak jarak, zeolit The use of solid catalyst in alcoholysis can increase the purity of ester because the separation process of solid catalyst is simpler than that of liquid catalyst. Prior to the ester formation, the ethanol was activated by the zeolite, forming alkoxide molecules. These molecules can attack the carbonyl functional group at the triglyceride in Jatropha oil and form ester. Jatropha oil, ethanol, and clinoptilolite zeolite powder were added into an autoclave equipped with manometer, thermometer, sampling valve, and heater. The autoclave was then powered up and rotated, and sampling was performed at time interval of 10 minutes. The reaction was performed at a temperature of 120°C and an autoclave rotation speed 110 rpm, with varied catalyst percentage and ethanol-oil equivalent ratio. The conversion was determined by analyzing the glycerol concentration of the lower layer with acetyl method. This study confirms that clinoptilolite type zeolite is effective catalyst for alcoholysis of jatropha oil. When the ethanol-oil ratio was 12.55 mgek/mgek, the catalyst percentage was 2.56% weight, the glyceride conversion reached 73%. Key words: alcoholysis, clinoptilolite, Jatropha oil, zeolite

Pemungutan Kurkumin dari Kunyit (Curcuma domestica val.) dan Pemakaiannya Sebagai Indikator Analisis Volumetri Ratna Sri Harjanti
Jurnal Rekayasa Proses Vol 2, No 2 (2008)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Analisa volumetri merupakan salah satu metode analisa kwantitatif, yang sangat penting penggunaannya dalam menentukan konsentrasi zat yang ada dalam larutan. Keberhasilan analisa volumetri ini sangat ditentukan oleh adanya indikator yang tepat sehingga mampu menunjukkan titik akhir titrasi yang tepat. Kurkumin, zat warna yang terkandung dalam umbi tanaman kunyit (Curcuma domestica val.) ternyata mampu berfungsi sebagai indikator karena terjadinya perubahan warna dari kuning muda coklat menjadi coklat pada pH sekitar 4,5 – 9,9. Untuk mengambil kurkumin dari umbinya, dilakukan dengan cara ekstraksi. Hasil ekstraksi disebut oleoresin. Dalam hal ekstraksi oleoresin, peranan pelarut, lama ekstraksi, suhu ekstraksi, dan kehalusan partikel sangat penting. Pada pengambilan zat warna kurkumin, kunyit yang sudah dihaluskan dikenakan proses ekstraksi dengan variasi suhu operasi, lama ekstraksi, dan kehalusan serbuk kunyit. Solven yang digunakan adalah etanol. Hasil ekstraksi kemudian didistilasi dan ditimbang . Kurkumin yang diperoleh pada kondisi optimum diuji kadarnya menggunakan TLC Scanner. Pemanfaatan kurkumin sebagai indikator dalam analisa volumetri dilakukan dengan cara titrasi menggunakan beberapa sampel asam basa dan membandingkannya dengan titrasi menggunakan indikator pp dan mo. Hasil penelitian menunjukkan bahwa kondisi optimum pengambilan kurkumin adalah pada suhu 70°C, ukuran partikel kunyit 100 mesh selama 120 menit menggunakan pelarut alcohol. Kurkumin yang dihasilkan memiliki kadar 5,158 mg/mL. Kurkumin yang akan digunakan sebagai indikator titik akhir pada analisa volumetri harus diencerkan terlebih dahulu menjadi 5% volume sebanyak 4 tetes. Kata kunci: indikator, kurkumin, titrasi, ekstraksi Volumetric analysis is one of quantitative analysis methods; a very important method used in determining the concentration of substances in solution. The success of this analysis was determined by the existence of an appropriate indicator that can show the exact end-point of titration. Curcumin, a natural dye contained in the plant root of turmeric (Curcuma domestica val.) was able to function as an indicator for the color change from light yellow brown to brown at pH around 4.5 to 9.9. Curcumin is extracted from the tuber which result is called oleoresin extraction. In the case of extraction of oleoresin, the role of solvent, extraction duration, temperature, and the fineness of particles is very important. In the present work curcumin pigment was extracted from turmeric paste in ethanol as solvent at varying operating conditions; i.e temperature, duration of extraction, and particle size of turmeric powder. The extract was further distilled and weighed. The curcumin obtained at optimum conditions was then determined using a TLC Scanner. The use of curcumin as an indicator in volumetric analysis was done by mean of titration using a few acid-basic samples. The results were compared with results from titrations using phenolphthalein (pp) and methyl-orange (mo) as indicators. The results showed that the optimum condition of curcumin extraction were at a temperature of 70°C for 120 minutes with a turmeric particle size of 100 mesh. The curcumin produced had a relatively high concentration of 5.158 mg/mL. In order to use it as an indicator for the end-point of volumetric analysis, the curcumin should be diluted to obtain 5% solution and use as much as 4 drops of the solution for the titration. Key words: indicator, curcumin, titration, extraction

Kinetika Reaksi Heterogen Etanolisis Minyak Jarak Kepyar (Ricinus communis) dengan Katalisator Zeolit Klinoptilolit Ratna Sri Harjanti; Sarto
Jurnal Rekayasa Proses Vol 3, No 1 (2009)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Minyak jarak kepyar mempunyai potensi untuk dijadikan biodiesel melalui proses alkoholisis katalitik. Zeolit alam klinoptilolit berpotensi digunakan sebagai katalisator dalam alkoholisis tersebut. Pada penelitian ini, alkoholisis minyak jarak dilakukan pada suhu tinggi dengan katalisator zeolit alam klinoptilolit dalam sebuah reaktor autoklaf yang dilengkapi dengan manometer, termometer, kran pengambil cuplikan, dan pemanas. Data percobaan menunjukkan bahwa pada kisaran waktu tertentu, peningkatan suhu dan putaran autoklaf mengakibatkan peningkatan konversi gliserid. Hasil analisis kinetika reaksi menunjukkan bahwa reaksi kimia pada permukaan katalisator merupakan langkah yang mengendalikan kecepatan reaksi keseluruhan. Kondisi proses yang relatif optimum terjadi pada waktu 60 menit, suhu 120°C dan kecepatan putaran autoklaf 110 rpm dengan perbandingan alkohol-minyak 12,56 mgek/mgek dan prosentase katalisator 2,56 %. Pada keadaan ini konversi gliserid mencapai 0,73 bagian. Ester dari minyak jarak yang diperoleh memiliki viskositas 8,0 cst, titik tuang -16,6°F, titik nyala 215°F, warna ASTM 1, dan nilai kalor 19.119 Btu/lb. Kata kunci: alkoholisis, klinoptilolit, minyak jarak, zeolit Castor oil of Ricinus communis has potential as a raw material for biodiesel synthesis through catalytic alcoholysis process. Clinoptilolite type natural zeolite is one of solid catalysts that can be used in the alcoholysis process. In the present work, the alcoholysis was carried out in an autoclave reactor equipped with manometer, thermometer, sampling valve, and heating element. The reaction occurred at elevated temperatures with the use of clinoptilolite as a solid catalyst. The experimental data indicated that in a certain reaction time range, an increase in temperature and autoclave rotation speed lead to the increase of reaction conversion. Calculation results showed that the overall reaction rate was controlled by chemical reaction at the catalyst surface. The optimum condition of the alcoholysis process was obtained at reaction time of 60 minutes, temperature of 120C and autoclave rotation of 110 rpm with the use of alcohol-oil ratio of 12.56 mgek / mgek and 2.56% (w/w) catalyst. At the optimum condition, the conversion could reach as high as 0.73. The obtaining esters had a viscosity of 8.0 cst, -16.6°F pour point, 215°F flash point, ASTM color of 1, and heating value of 19,119 Btu/lb. Keywords: alcoholysis, clinoptilolite, castor oil, zeolite

Kitosan dari Limbah Udang sebagai Bahan Pengawet Ayam Goreng Ratna Sri Harjanti
Jurnal Rekayasa Proses Vol 8, No 1 (2014)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Industri pengolahan udang banyak menimbulkan hasil samping berupa limbah kulit udang yang belum dimanfaatkan secara optimal. Hal ini menyebabkan limbah kulit udang kurang memiliki nilai ekonomis dibanding dengan mengolahnya menjadi kitin dan kitosan. Kitosan banyak digunakan di berbagai industri antara lain sebagai bahan pengawet pengganti formalin. Bahan pengawet merupakan bahan tambahan makanan yang dibutuhkan untuk mencegah aktivitas mikroorganisme agar kualitas makanan senantiasa terjaga sesuai dengan harapan konsumen. Kemampuan kitosan dalam menekan pertumbuhan bakteri disebabkan kitosan memiliki polikation bermuatan positif yang mampu menghambat pertumbuhan bakteri dan kapang. Dalam penelitian ini akan dilakukan pembuatan kitosan dengan variasi konsentrasi NaOH, sehingga akan diperoleh variasi rendemen dan derajad deasetilasi. Kulit limbah udang mengalami proses deproteinasi dengan larutan NaOH (3,5% b/v) selama dua jam pada suhu 65°C dan proses demineralisasi dalam larutan HCl 1 N (1 gram sampel : 15 mL larutan HCl) selama satu jam pada suhu kamar. Proses deasetilasi dilakukan dengan memanaskan kitin dalam larutan NaOH (30%, 40%, 50%, dan 60% b/v) selama 4 jam pada suhu 100°C. Selanjutnya dilakukan pengamatan pengaruh derajad deasetilasi terhadap kemampuan kitosan sebagai bahan pengawet. Pengamatan ini dilakukan dengan mengaplikasikan kitosan dalam pengawetan daging ayam. Dipilih daging ayam karena sekarang ini banyak sekali dibuat ayam goreng yang dijual dalam gerobak-gerobak di pinggir jalan yang menggunakan bahan kimia berbahaya sebagai pengawetnya. Kitosan yang berasal dari limbah kulit udang dapat digunakan sebagai bahan pengawet daging ayam, tanpa mengubah rasa dan aroma khas daging ayam. Waktu perendaman terbaik adalah 45 menit pada kitosan 2%. Sedangkan aplikasi kitosan sebagai bahan pengawet diperoleh kondisi terbaik pada derajad deasetilasi 70,34%. Kata kunci: kitosan, limbah udang, pengawet makanan, ayam goreng Shrimp industries have to deal with shell solid waste. On the other hand, this shell solid waste can be utilized to produce citin and citosan. One of the beneficiations of citosan is for food preservation. This ability is based on the existence of poly cation with positive charge that is responsible for the inhibition of bacteria growth. In this study, NaOH was varied to produce citosan from shrimp shell resulting rendemen and deasetilation degree. Deproteination of the shrimp shell was done using NaOH (3,5% b/v) for 2 hours, at temperature of 65°C, while demineralization was conducted using HCl 1 N (1 gram of sample: 15 mL of HCl) for 1 hour at room temperature. Deasetilation was done by heating citin in NaOH with concentration of 30%, 40%, 50%, and 60% b/v for 4 hours at temperature of 100°C. Further, observation on the ability of resulted citosan as food preservation was conducted. Chicken meat was choosen as sample to represent the abundance restaurants selling these product. It has been found that citosan from shrimp shell solid waste can be utilized as food preservation agent for chicken meat without changing the taste and texture of the meat. The optimum condition is 45 minutes with citosan concentration of 2% with deasetilation degree of 70,34%. Keywords: citosan, shrimp shell solid waste, food preservation, fried chicken.

Optimasi Pengambilan Antosianin dari Kulit Buah Naga Merah (Hylocereus polyrhizus) Sebagai Pewarna Alami pada Makanan Ratna Sri Harjanti
CHEMICA: Jurnal Teknik Kimia Vol 3, No 2 (2016): Desember 2016
Publisher : Universitas Ahmad Dahlan

The addition of synthetic colors in foods in an attempt to attract the attention of consumers, not a ban, but if the dye used is a dye that is unusual for the food, it is harmful to health. One source of natural pigments that can be used is the red dragon fruit skin. These skins contain anthocyanins potential as a dye.Â Â Â Â Â Â Â Â Â Â Â Â In this reasearch, the observed red dragon fruit skin moisture content and size of the powder. It also conducted a stirring speed variation during the extraction process. While variable temperature, time, and solvent refers to the optimum conditions of research that has been done. Analysis of the results was conducted to determine pH, anthocyanin concentration and yield results.Â Â Â Â Â Â Â Â Â Â Â Â Based on the results obtained, the smaller the water content contained in the skin, giving absorbance values are higher. This shows that extractable anthocyanins levels are also higher. The lowest levels of the skin can be achieved in this study was 6%. The smaller the grain size, the higher the anthocyanin content. The smallest grain size achieved was 100 mesh. The highest mixing speed in this study was 300 rpm, the higher the stirring speed, the higher the anthocyanin content fetched.Â Â Â Â Â Â Â Â Â Â Â Â Organoleptic tests were conducted to study the effect of anthocyanins on the quality of the food shows that the addition of anthocyanins provide the appropriate color and do not significantly affect flavor and aroma. So it can be used as a natural dye for food.

Pupuk Organik dari Limbah Pabrik Gula Madukismo dengan Starter Mikrobia Pengurai Untuk Menambah Kandungan N, P, K Ratna Sri Harjanti
CHEMICA: Jurnal Teknik Kimia Vol 4, No 1 (2017): Juni 2017
Publisher : Universitas Ahmad Dahlan

AbstrakÂ Blotong is sugar mill waste slude in the form of dark, often dumped, causing pollution and odor. Blotong produce about 3,8 % of cane milled by a sugar factory unit. While vinasse is waste water generated from the process of making alcohol. In the process of making one liter of alcohol will produce as much as 13 liters of vinasse. Vinasse contain many elements K, while blotong contains a lot of elements of N, P, dan Ca. This allows for composting blotong with the addition of vinasse to produce organis fertilizer. Blotong and vinasse may be seen in the PG Madukismo.Organic fertilizer through composting mixture of blotong and vinasse using microbial starter EM-4 and X-Compost can be done easily in the home environment. To determine the optimum process conditions to produce organic fertilizer, need to be varied ratio of blotong and vinasse. Composting reaction carried out for thirty days with observed in temperature and pH. Further analysis of N, P, K and C/N ratio.Based on the results obtained, the use of starter microbes X compost more prospective than using starter microbes EM-4. The compost produced by the starter microbes X-compost contains N, P, K which is much higher than the compost produced by the starter micobes EM-4. As for the addition of vinasse, will give optimum results in the addition of vinasse 25% of the weigth of blotong.Â Keywords: blotong, vinasse, compost, microbe

Biodiesel dari Limbah Pabrik Gula dan Minyak Jarak Pagar (Jatropha curcas) dengan Katalisator Zeolit Alam Klinoptilolite Ratna Sri Harjanti; Anugrah Perdana Rahmanta
CHEMICA: Jurnal Teknik Kimia Vol 2, No 2 (2015): Desember 2015
Publisher : Universitas Ahmad Dahlan

The fuel price increase with the increase of the number of transportation due to the increasing numbers of the population. Indonesia with more than 200 million people in need of transportation fuels in the form of gasoline and diesel in large quantities. Currently the main source of transportation fuels derived from petroleum. Premium production in Indonesia is about 62 million barrels and production of about 87 million barrels of diesel fuel. The product does not include the use for other needs, such as lubricating oil, kerosene, avgas, as well as other materials. This is particularly worrying given the oil reserves are dwindling. One of the alternative energy for transportation fuels is biodiesel as a substitute for diesel fuel.The castor oil has potential to be used as biodiesel. Fusel oil is a sugar mill waste containing alcohol. The reaction between castor oil and fusel oil with natural zeolite catalyst klinoptilolite be referred to as alcoholysis reactions that produce esters. Castor oil and fusel oil mixed with zeolite powder klinoptilolite that previously had been heated in a separate place until it reached its boiling temperature. Three neck flask fitted with a thermometer, hoses trailer makers, heater, and the agitator on 100 rpm with 100 oC of temperature. Snapshot taken at intervals of 30 minutes each. Conversion reaction calculated by analyzing the levels of glycerol bottom layer by means asetin. Alcoholysis fusel oil and castor oil with natural zeolite catalyst klinoptilolite produce esters that are approaching the properties of diesel oil with a calorific value of 19 119 Btu/lb. Optimum conversion of 57 % was obtained in alcohol - oil ratio of 9.29 mgek/mgek and the addition of a catalyst as much as 2.56% of the weight of oil.

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