Experimental and Modeling Studies of the Reaction Kinetics of Alkaline-Catalyzed used Frying Oil Glycerolysis using Isopropyl Alcohol as a Reaction Solvent

An alkaline catalyzed glycerolysis of used frying oil using sodium hydroxide and isopropyl alcohol as solvent was investigated. A reaction kinetic model considering glycerol-triglyceride solubility and a second order kinetic mechanism was also developed. The effect of variations in glycerol to used frying oil molar ratio (RGO = 2:1 to 4:1) and temperature (60 to 80ºC) on the rate of reaction were investigated, while the isopropyl alcohol to used frying oil ratio (2:1 v/w) and the concentration of catalyst (3 wt% based on used frying oil) were held constant. Results showed that both RGO and temperature affected the glycerolysis reaction kinetic, with the effect of RGO was found to be superior. The proposed model showed its good agreement with the experimental data. Glycerolysis at RGO = 3:1 and 80ºC in 90 min was found to be a relatively good condition, where 91.03% of tryglceride was converted into MG

Sorption Mechanism of Lead Ions From Aqueous Solution By Imperata Cylindrica Dried Leaf Particle: Effect of Temperatures

This study was conducted to investigate the sorption mechanism of Pb2+ ions from aqueous solution onto Imperata cylindrica (IC) dried leaf particles. The effect of temperatures (30, 35 and 40oC) was scrutinised from a batch adsorption system using a synthetic liquid waste containing Pb2+ ions. Adsorption of lead ions mechanism was investigated by intraparticle diffusion model. The results showed that higher adsorption rate occurred at higher temperature, and obeyed the pseudo second order adsorption model. The overall rate of lead uptake was found to be controlled by external mass transfer at the beginning of adsorption, then gradually changes to intraparticle diffusion controlled at a later stage. The intraparticle diffusion constant increased with increasing temperature. The values of effective diffusion coefficient (Di) increased at higher temperatures, which were 5.5466 × 10−9, 6.8215 × 10−9, and 7.3726 × 10−9 m2/s at 30, 35, and 40 ◦C, respectivel

Dissolution Rates of Mangosteen (Garcinia mangostana L.) Pericarps Extract Granules in Synthetic Human Gastrointestinal Fluid

Mangosteen (Garcinia mangostana L.) pericarps contain prenylated xanthone derivates, which exhibit some pharmacological activities, such as antiinflammatory, antihistamine, antibacterial, antivirus, antifungal, antioxidant, and antiulcerogenic. The purpose of this research was to study the dissolution rates of mangosteen pericarp extract granules in synthetic human gastrointestinal fluid at various pH and temperatures, which include experimental and modeling works. The granules were prepared by wet granulation of methanol extracts of mangosteen pericarps with addition of 25% w/v Arabic gum and 5% w/v maltodextrin. Dissolution rate study was performed by dissolving 0.5 g granules in 500 mL of 0.02M phosphate buffer solution with constant agitation at various pH (5.5, 6, 6.5, 7 and 7.5) and temperatures (30, 37 and 40oC) for two hours. Every 20 minutes, a liquid sample was withdrawn from the system for xanthone analysis. The results showed that mangosteen pericarps granules dissolution rates increased with pH under acidic condition. At pH 7.5 (basic condition), the dissolution rate was faster than that at pH 7. As expected, the dissolution rates were higher at higher temperatures. The semi empirical Korsmeyer-Peppas model showed its superiority over other models to predict the mangosteen pericarps granules dissolution rates. However, the mass transfer model proposed in this work also agreed well with the experimental data with error percentages closely similar to that of Korsmeyer-Peppas model

Removal of Cyanides from Gadung (Dioscorea hispida Dennst.) Tuber Chips using Leaching and Steaming Techniques

Gadung (Dioscorea hispida Dennst.) has been considered as one of staple foods in Indonesia. However, its high cyanides content has limited its utilisation for commercial food production. This work is aimed to investigate the removal of cyanides content from gadung tuber chips through two consecutive treatments, i.e. leaching and steaming and to propose mathematics model for the leaching process. The results showed that processing water flow rate and leaching time affected the efficiency of cyanides removal in the leaching process. The proposed mathematical model was able to represent the removal of cyanides through leaching process very well. The cyanides content removal was also found to be affected by steaming time. Best processing condition was at leaching using 5.00 10-5 m3.s-1 for 3,600 s, followed by steaming for 3,600 s to obtain cyanides content of 29.9 mgkg-1. While the yielded gadung tuber chips are considered as safe for consumption, further research on physicochemical characteristic of the gadung tuber flour is necessary for its utilisation consideration

Penurunan Sianida dalam Umbi Gadung dengan Proses Leaching yang Bekerja Batch

Yam is a tuber plant usually grown in tropical area. The starch contained is potential to be developed as food material like flour as a substitute for wheat in bread making. Although yam tubers were found to have high amount protein and amino acid, they also contained some antinutritional components like cyanogen substances, which can be toxic for human. Cyanogens substances were reduced by batch leaching process which used water as a leaching agent. Yam tuber was sliced into small chips and placed inside the leaching column. Later, 3 L per minute water was flown to the heap of yam chips. The changes of cyanogens content in the tuber chips were analyzed and, presented as HCN equivalent in mg per kg fresh sample every 0.5 hour. After the process, the cyanide content in the yam tuber decreased to an average of 24 ppm at solvent-to-solid ratio from 15 to 40 l/kg and leaching time 2.5 hours

Preparation, Proximate Composition and Culinary Properties of Yellow Alkaline Noodles from Wheat and Raw/Pregelatinized Gadung (Dioscorea Hispida Dennst) Composite Flours

The steady increase of wheat flour price and noodle consumptions has driven researchers to find substitutes for wheat flour in the noodle making process. In this work, yellow alkaline noodles were prepared from composite flours comprising wheat and raw/pregelatinized gadung (Dioscorea hispida Dennst) flours. The purpose of this work was to investigate the effect of composite flour compositions on the cooking properties (cooking yield, cooking loss and swelling index) of yellow alkaline noodle. In addition, the sensory test and nutrition content of the yellow alkaline noodle were also evaluated for further recommendation. The experimental results showed that a good quality yellow alkaline noodle can be prepared from composite flour containing 20% w/w raw gadung flour. The cooking yield, cooking loss and swelling index of this noodle were 10.32 g, 1.20 and 2.30, respectively. Another good quality yellow alkaline noodle can be made from composite flour containing 40% w/w pregelatinized gadung flour. This noodle had cooking yield 8.93 g, cooking loss 1.20, and swelling index of 1.88. The sensory evaluation suggested that although the color, aroma and firmness of the noodles were significantly different (p ≤ 0.05) from wheat flour noodle, but their flavor remained closely similar. The nutrition content of the noodles also satisfied the Indonesian National Standard for noodle. Therefore, it can be concluded that wheat and raw/pregelatinized gadung composite flours can be used to manufacture yellow alkaline noodle with good quality and suitable for functional food

PRODUCTION OF ETHANOL BY FED-BATCH FERMENTATION

The production of ethanol, from glucose in batch and fed batch culture, was investigated. In the fed batch culture, the glucose feeding was added into the culture at 16th hour of fermentation. The effects of different glucose concentration feeding rates on ethanol fermentation were investigated for fed batch culture. The 2gL-1hr-1 glucose concentration feeding rate was found to give higher ethanol yield (2.47 g ethanol g glucose-1), with respect to substrate consumed as compared to 8 gL-1hr-1 (0.23 g ethanol g glucose-1) and 4 gL-1hr-1 (0.20 g ethanol g glucose-1). The ethanol yield with respect to substrate consumed obtained in batch culture was 0.81 g ethanol g glucose-1. The fed batch culture at 2 gL-1hr-1 glucose concentration feeding rate was proven to be a better fermentation system than the batch culture. The specific growth rate, specific glucose consumption rate and specific ethanol production rate for the fed batch fermentation, at 2 gL-1hr-1 glucose concentration feeding rate, were 0.065 hr-1, 1.20 hr-1 and 0.0009 hr-1, respectively

Preparation of Wine from Jackfruit (Artocarpus heterophyllus lam)Juice Using Baker yeast: Effect of Yeast and Initial Sugar Concentrations

The overproduction of jackfruit (Artocarpus heterophyllus Lam) during harvest season and its short shelf-life have caused serious losses for farmers. Fortunately, high sugar content of the fruit pulp makes the juice a potential substrate for wine production. This work was purposed to investigate the effect of yeast and initial sugar concentrations on jackfruit juice wine fermentation. Clarified jackfruit juice of 14 % w/w sugar concentration was fermented using 0.5 to 2.0 % w/v Baker’s yeast (Saccharomyces cerevisiae) under anaerobic condition at 30°C for 14 days. Samples were collected daily for ethanol and sugar contents analysis. The profile of sugar and ethanol concentration as function of fermentation time, showed that higher yeast inoculums rate and initial sugar concentrations inhibited growth of yeasts. The fermentation of original jackfruit juice of 14 % w/w sugar concentration using 0.5% w/v yeast for 9 days was the best to produce a good quality wine with 12.13% v/v of ethanol and specific jackfruit aroma

Solubility of Corosolic Acid in Supercritical Carbon Dioxide and Its Representation Using Density-Based Correlations

The solid solubilities of 2R,3β-dihydroxyurs-12-en-28-oic acid (corosolic acid) in supercritical carbon dioxide (SCCO2) have been measured using a dynamic method at (308.15, 313.15, 323.15, and 333.15) K over a pressure range of (8 to 30) MPa. Prior to solubility measurements, the accuracy of the experimental apparatus was examined by measuring solubilities of squalene in SC-CO2 and comparing them with literature. The corosolic acid solubilities ranged from a corosolic acid mole fraction of 3.28 3 10-11 at 333.15 K and 8 MPa to 7.43 3 10-2 at 333.15 K and 30 MPa. The del Valle and Aguilera andMendez-Santiago and Teja (density-based) models were used to correlate the experimental data. The calculated solubilities showed good agreement with the experimental data in the temperature and pressure ranges studied

EFFECT OF SOLVENT FLOW RATE ON THE SUPERCRITICAL CARBON DIOXIDE EXTRACTION OF ANDROGRAPHOLIDE FROM ANDROGRAPHIS PANICULATA

Malaysia is one of the major medicinal plants (Andrographis paniculata) producers in the world. Extraction of bioactive component (andrographolide) from ground dried leaves of this plant using supercritical carbon dioxide has been studied. The effect of solvent flow rates ranging from 7.95 × 10-6 to 6.36 × 10-5 kg/s on the extraction efficiency has been investigated. The extraction yield increased with the increase of solvent flow rate from 7.95 × 10-6 to 3.18 × 10-5 kg/s. However further increase of solvent flow rate reduced the extraction yield. Therefore, an optimum solvent flow rate at 3.18 × 10-5 kg/s was obtained for the system under study. The extraction process was found to be controlled by intraparticle diffusion of the andrographolide in the starting leaves particles