Seminar Nasional Teknik Kimia Kejuangan
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Pengaruh Penambahan Zat Anti-browning Alami pada Kentang
Get PDFBrowning reactions often occur in the processing of potatoes, browning can change the taste or texture of food, so it can lead to lower the value of food quality. Browning can be caused by enzymatic or non-enzymatic reactions. Enzymatic browning occurs because the substrate containing the phenol group reacts with the polyphenol oxidase enzyme to form a brown colored pigment.To inhibit the browning reaction can be done with the addition of acid or the addition of firmness agent. In this study used salt kitchen, lemon juice, and citric acid to inhibit browning in potatoes. The addition of antibrowning agent was done on various variations of 0,5%, 1,0%, and 1,5% (w/v). Antibrowning activity test was analyzed by measuring the color intensity of the solution using spectrophotometer. The results will be analyzed using ANOVA with design expert software. Experimental results obtained that NaCl, lemon juice, and citric acid can inhibit the occurrence of browning in potatoes by producing a lower absorbance when added antibrowning substances. Analysis of variance (ANOVA) showed significant results on the effect of different antibrowning substances, while the effect of variation in levels did not give significant results. The best result is the addition of citric acid with a level of 1,5% (w/v) with inhibition of 76,34%
Evaluasi Kinerja Gasifier Up-draft Dengan Umpan Limbah Biomassa Kayu Mahoni Dari Industri Mebel
Get PDFWood waste from furniture industries was gasified using up-draft gasifier type. The type of wood was used is mahogany. Operation of the gasifier is batch model with wood waste concumption per batch is 4 kg, 7 kg and 9 kg. Equivalent ratio of air used is 24,73%, 14,13% and 10,99%. The mahogany have properties of ultimate analysis is 13,8%-wt moisture content, 65,8%-wt volatile matter, 48,7%-wt fixed carbon and 2,24%-ash. Temperature profile of gasifier observed during operation as a time function. The gasifier also integrated with scrubber buble column and water as a solvent to minimize tar in the producer gas. The scrubber buble column was used has efficiency removal is 57,41%.
Sintesa Superabsorben dari Natrium Alginat dengan Metode Grafting-Crosslinking dengan dan Tanpa Komposit
Get PDFIndonesia is the second largest algae producer in the world. Nevertheless, the algae is just dried and exported or extracted to become carrageenan, sodium alginate, or agar. According to its chemical composition, the algae has a potency to be developed such as biodiesel, pharmaceutical products, etc. The goal of this research is to develop superabsorbent based on sodium alginate. Superabsorbent is a hydrophilic material which can absorb and retain large amount of water. Commercial superabsorbent is mostly synthesized from chemical substances which are less eco-friendly. The synthesis of superabsorbent was done by reacting 5% sodium alginate solution with acrylic acid and/or acrylamide at the certain ratio: 1:0; 1:3; 1:1; 3:1; and 0:1, using ammonium persulfate as initiator. To crosslink and strengthen the macromolecules was used N.N’-methylenebisacrylamide as crosslinker, and bentonite as composite. Water absorbency capacity was measured in pH 3, 7, and 11 solution.The highest water absorbency was obtained at 5%-w/w sodium alginate; 0,02 mol/L initiator; 1:1 ratio of acrylic acid and acrylamide; 0,007 mol/L crosslinker, and without composite in pH 7 solution
Pengaruh Berbagai Proses Dehidrasi Pada Pengeringan Daun Stevia Rebaudiana
Get PDFStevia sugar is derived from the Stevia leaf extraction process, which is a natural sweetener, low-calorie and easily digestible. Stevia leaves are sweet because they contain the main glycosides Stevioside and Rebaudioside A. Stevia has many benefits, especially for health. The Stevia leaves\u27 dehydration process will affect Stevia sugar gain in subsequent processing. The objective of this research was to find out the best dehydration method of fresh Stevia leaf that can produce dried leaves with the lowest moisture content, similar content to the original composition, and no color changing to brown or black. Leaf dehydration methods used in this research are sun drying, shade drying, drying with oven incubator, and use of food dehydrator. The result shows that the temperature, drying airflow rate, dryer airflow pattern, and relative humidity were influence the drying process. The best results were given by the dehydration process by using food dehydrator at 40.56 ° C for 4 hours, with moisture content of 5.71%, Stevioside content of 12.37%, and dried leaves that remain green
Kajian Proses Pengolahan Limbah Bambu Apus (Gigantochloa Apus) dengan Menggunakan Metode Hydrothermal Liquefaction
Get PDFBamboo has received huge attention because it grows fast and has fine mechanical properties. Hydrothermal liquefaction (HTL) is one of the methods devoted to the degradation of cellulose, hemicellulose,lignin and other components contained in bamboo. This Method applies thermal disintegration of biomass in high-pressure hot water. HTL involves direct liquefaction of biomass, in the presence of water acts as reactant as well as catalyst to convert biomass into bio-oil. Employing hydrothermal liquefaction processing of biomass provide sustainable production of bioproducts that reduce some environmental problem caused by the accumulation of organic waste .In this research bamboo was treated in autoclave reactor with capacity 250 ml. The temperature of the reaction was 240oC at initial pressure was 1,0 MPa, and with the residence time about 30 minutes. Water to biomass ratio was at 2:20. GC-MS analysis results showed that several potential compounds were obtained such as dimethylformamide ( for production of acrylic fiber and plastic), furfural and furan (for production of pestiside or biofuel), phenol and some organics acid (for wood preservatives)
Synthesis of Soluble Carboxymethyl Chitosan from Low Molecular Weight of Chitosan
Get PDFCarboxymethyl chitosan was obtained under heterogeneous conditions as a product of the reaction of chitosan and monochloroacetic acid in the presence of sodium hydroxide. In the previous experiment, showed that the solubility of carboxymethyl chitosan increased with the decreased of molecular weight of chitosan. However, the solubility of carboxymethyl chitosan in water and acid solvent were still necessary to be maximized. In this experiment aims to determine the effect of condition process such as NaOH concentration, mass ratio chitosan to monochloroacetic acid, and time eterification towards degree of substitution (DS) and the solubility of carboxymethyl chitosan. Some variables that were used to synthesize carboxymethyl chitosan were concentrations of sodium hydroxide (20-50 %w/v), etherification times (1-4 hr), and mass ratio chitosan to monochloro acetic (1:1, 2:1 and 1:2 (v/v). Characterization performed on the synthesized carboxymethyl chitosan including FTIR, degree of substitution (DS), and solubility properties. The solubility of carboxymethyl chitosan increased almost linearly with increasing concentration and etherification times. The maximum DS value being obtained for carboxymethyl chitosan sample synthesized in 50% (w/v) sodium hydroxide with 4-hour reaction and temperature at 60oC, that is 1.79 and solubility of carboxymethyl chitosan were 86.3%; 95.2%; 92.3% in water, 1% of HCl and 1% of CHCOOH respectively
Total Reducing Sugar Production from Cassava Starch Degradation by Hydrothermal Process and Sonication Treatment
Get PDFStarch is one of the most abundant carbohydrates from in cassava tubers. Cassava is very a promising feedstock for reducing sugar and oligosaccharides production in food and pharmaceutical industries. Nowadays, hydrothermal process is one of a promising process for degradation of starch into reducing sugars. In this research, sonication pre-treatment is given to increase the resulting product. The effect of reaction time in hydrothermal process in reducing sugar production was studied. Cassava starch suspensions in aquadest (1:20 (w/v)) were treated with sonication process at frequency of 20 kHz with amplitude 50% and heating at 40oC for 15 min. After sonication process, sonication product was processed in hydrothermal process at 100°C and 200 Bar in various hydrothermal time (15-120 min). The solid products were analyzed using Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). And liquid products were analyzed by DNS method. The results from SEM showed that can be destruction of the starch granule and XRD showed that changes the crystallographic pattern of the starch granule. And concentration of total reducing sugar is increased with increasing hydrothermal time
Synthesis and Characterization of Superabsorbent Polymer (SAP) based on Starch and Acrylic Acid
Get PDFSuperabsorbent polymer (SAP) is hydrophilic polymer networks that can absorb high amount of water and eco-friendly. SAP was synthesized by graft copolymerization of acrylic acid on to the backbone of starch using N,N-methylenebisacrylamide (MBA) as a crosslinker and potassium persulfate (KPS) as a free radical initiator. This material was synthesized in nitrogen atmosphere at 70oC for two hours using of acylic acid (after 40% neutralization with NaOH). The influence of amount crosslinker agent to water absorbency was investigated. The polymer product was characterized by Fourier Transform Infrared Spectroscopy (FTIR). Based on the result show that superabsorbent polymer had an optimum crosslinker value of 1,5% wt acrylic acid with water absorbency obtained were 241.11 g/g dan 279 ml/ml
Kecepatan Pelepasan Urea dari Controlled Release Fertilizer (CRF): Pengaruh Rasio Carboxymethylcellulose (CMC) – Karagenan
Get PDFBeads of carboxymethylcellulose (CMC)-carrageenan for controlled release fertillizer matrix (CRF) are prepared based on different blend with CMC:carragenan weight ratio of 1:0, 1:0.5, and 1:1. CMC-carrageenan beads gel was chemically modified using glutaraldehyde solution (4%) as the crosslinker and applied to control the urea release rate. This research proposed mathematical model describing the mass transfer rate of urea release and determined the effect of ratio CMC-carrageenan blend on the parameters of urea release rate from the beads gel in water. The beads gel were crosslinked by beads gel immersion method and thermal curing at 110oC for 25 minutes. Urea was loaded in the beads gel. The rate release of urea from crosslinked beads gel in water was determined by measuring the concentration of urea in various time of immersion. Result showed that the mathematical model arranged could be describe the mass transfer rate of urea release. The release rate of urea was decreased with the increasing of carrageenan amount in ratio blend. The range constant mass transfer rate was around 0.0444/minute until 0.0528/minute, while the range equillibrium constant was around 0.000524 until 0.000897 gram of solid/mL. The optimum weight ratio CMC:carrageenan of 1:1 might be potential for urea controlled release
Pengawetan Alami Kayu Ketapang (Terminalia catappa) Menggunakan Ekstrak Daun Sambiloto (Andrographis paniculata) sebagai Bahan baku untuk Produk Interior
Get PDFWood has been widely used as raw material for making products needed by human, such as building, furniture, interior and exterior products. Indonesia has more than 4000 species of woods, but 80% of the woods are categorized as low-durability class, so for these types of wood require preservation to extend its life service. Since chemical preservation methods are not environmentally friendly, a natural method was used in this study. Research on preservation of Ketapang wood (Terminalia catappa) using Sambiloto (Andrographis paniculata) leaf extract for the manufacture of home interior products has been carried out. Ketapang wood was preserved by hot bath at temperature of ± 80oC using Sambiloto leaf extract with variation of concentration of 10%, 12.5% and 16.67% for immersion time of 1 hour, 2 hours and 3 hours. The retention value of each variation was calculated and compared with the preservative value for the interior product of SNI 03.5010-1.1999 (≥ 8 kg/m3). The result of the study has been in accordance with SNI, which is 9,6 kg/m3, obtained at the concentration of preservative 12.5% for 3 hours immersion time