Production, Characterization and Glycerine Analysis of Soybean Oil and Its Biodiesel

Aims: To examine the viability of Soybean Oil as a feedstock for Biodiesel production by carrying out its characterization and examining its thermodynamic properties to see if they are within ASTM limits. Study Design: Place and Duration of Study-The production was conducted in the Department of Mechanical Engineering of the University while the characterization of the Biodiesel was conducted at the Postgraduate Research Laboratory. Samples of Glycine ma (L.) merril were obtained from a local market in the Akure town of Ondo State, Nigeria in October of 2014. Methodology: Oil Extraction-The oil was extracted using soxhlet extractor, but before extraction the soybeans were crushed in a blender to increase the area exposed to the petroleum ether solvent. The extraction flask was dried in an oven at 105°C and the weight was measured after cooling. 2.5 g of soybean was poured into the flask and leached for 5 hours after which extraction flask was removed from the mantle heater after all the petroleum ether was removed with rotary evaporator and the oil was oven dried at 105°C for one hour to remove any water present. The flask was finally cooled to room temperature in a desiccators and the weight of the flask and dried oil was again measured. Transesterification and Glycerine Analysis Process: 50 mg of the extracted oil was esterified 5 times at 95°C with 3.5 ml of the 0.5 M KOH of dried methanol. The mixture was neutralized using 0.7M HCL. 3 ml of 14% boron triflouride in methanol was added and the mixture was heated for 5 minutes at 90°C to achieve completed methylation process. The fatty acid methyl esters were thrice extracted from the mixture with redistilled methanol. The content was concentrated to 1mL for gas chromatography analysis and 1 µL was injected into the port of the Gas Chromatograph analyzer. Results: most of the pertinent parameters for the determination of validity were found to be within ASTM limits, namely: Flash Point (135°c / 130°c min); Kinematic Viscosity (4.80 / between 1.9 - 6); Cetane number (55 / 47 min); Copper Strip Corrosion (1 / 3 max); %Carbon Residue (0.12 / 0.050); %Sulphated Ash (0.044 / 0.020). Conclusion: Given the obviously good numbers associated with the study relative to ASTM standards, Soybean is a viable source of Biodiesel. However, further study could explore the use of Soybean chaff and other waste matter obtainable from it rather than the entire crop.

Separation and estimation of diacetyl and acetoin in milk

SummaryTwo methods are described for the separation of diacetyl and acetoin in milk by steam distillation. In the first method, acetoin is measured in the residue remaining in the extraction flask after steam distillation while diacetyl is measured in the first 10 ml of distillate which contains 35% of the acetoin and 100% of the diacetyl. Increases in the volume of residue taken for analysis decreased colour development by acetoin. In the second and preferred method, diacetyl is measured in the first 10 ml of distillate and acetoin in the second 10 ml of distillate which contains about 24% of the added acetoin. Diacetyl in both methods is measured by a modification of the method of Prill & Hammer (Walsh & Cogan, 1974) and acetoin by the Westerfeld (1945) procedure.

Collaborative Study of Microbiological Assay of Oxytetracycline in Feeds

A collaborative study was made of a modification of the official AOAC method for the determination of oxytetracycline in feeds. This cylinder plate method uses Bacillus cereus var. mycoides, ATCC No. 11778, as the test organism. The modification consists of using a 20 g instead of a 10 g sample, of using an extraction flask instead of a mortar and pestle or a blender, and of filtering the assay solution. The average recovery of oxytetracycline by 12 collaborators was 92.4% with an average coefficient of variation of 13.5%. Assay precision, determined by computing standard deviations on the differences between pairs of similar materials, was estimated to be 7.4% at 10 g/ton and 5.9% at 25 g/ton. The method is recommended for adoption as official, first action.

Analytical Methodology of Oxytetracycline in Feed

Two experiments were conducted to evaluate modifications of the AOAC method for determining oxytetracycline (OTC) in feed and 4 methods of preparing compensating curves for this modified method. The modifications involved use of a 20 g sample, extraction in extraction flask, and filtration of the assay solution. Compensating curves were prepared from blank feed extracts and extracts of test blends in which OTC was inactivated by either boiling in sodium hypochlorite, passing through adsorption columns, or refluxing 18 hours. At levels of 25 g OTC/ton and higher, the modified AOAC method gave 100% recovery with a coefficient of variation of 8.1%. At 10 g/ton, 92% was recovered with a coefficient of variation of 11.0%. Compensating curves showed 58—91% recovery at 10 g OTC/ton with an average coefficient of variation of 21.8%. The method will be submitted to collaborative study.