In order to obtain the optimal extraction conditions of anthocyanin in purple eggplant peel, purple eggplant peel was used as experimental material, the single factor test conditions were screened through determinating the content of anthocyanin in the crude extraction solution. The optimum range of the concentration of ethanol, the ratio of liquid and material ratio, the time of extraction, and the temperature of extraction were determined. Then the quadratic regression orthogonal rotation combination design was used to optimize the extraction process of anthocyanin. Four factors and regression model of content of anthocyanin were obtained. The results showed that the factors affecting the extraction efficiency of anthocyanins were as follows: the concentration of ethanol > the temperature of extraction > the ratio of liquid and material ratio > the time of extraction. Finally, the optimum extraction conditions of anthocyanin extracted from purple eggplant peel were obtained as follows: the concentration of ethanol was 78.6%, the ratio of liquid and material ratio was 60:1 (mL g-1), the temperature of extraction was 20 ℃, the time of extraction was 150 min, and the content of anthocyanin was up to 4.2399 (mg g-1). The crude extracting solution of anthocyanin was clear and stable, and the color of stable extracting solution was dark red. The validation experiment was carried out at the optimized conditions, and the preferable results were obtained, which showed that the optimization of extraction technology of anthocyanin in purple eggplant peel by this method was reliable, and which had practical guiding significance.
Original Research Article
Dec. 20, 2019
Proximate Analysis and Quantification of Polycyclic Aromatic Hydrocarbons in Some Smoked and Roasted Food Items
Omodara Niyi Basil, Fehintola Ezekiel Oluwaseun, Ojo Babatunde Moses
Page Numbers : 127-131
DOI : 10.36348/sijcms.2019.v02i08.001
Analysis for the presence and concentration of sixteen Polycyclic Aromatic Hydrocarbons (PAHs) were carried out in roasted plantain, roasted meat and smoked fish in Ondo, Ondo State Nigeria. The proximate analysis was carried out using the method of AOAC. A representative portion of about 5 g of sample was taken from the homogenized sample and extracted with ultrasonicator using three solvent systems: methanol, methanol: dichloromethane (1:1v/v) and dichloromethane. The aromatic fraction was subsequently analyzed with Gas Chromatography (GC/FID). The results showed that the percentage fat content ranges from 4.32 % roasted plantain to 19.27 % roasted meat, protein content ranges from 6.07 % roasted plantain to 44.86 % smoked fish, the moisture contents ranges from 19.39 % smoked fish to 58.31 % roasted plantain while the carbohydrate ranges from 8.89 % roasted meat to 22.09 % roasted plantain. From the result of GC/FID analysis, sixteen PAHs found in the samples ranged from 0.99 – 0.10 μg/kg, 0.01 – 0.73 µg/kg and 0.00 – 0.72 µg/kg for roasted plantain, roasted meat and smoked fish respectively. The sum of all PAHs concentration found in the samples was 6.16 µg/kg for roasted plantain, 6.22 µg/kg for roasted meat and 4.97 µg/kg. The ratios of phenathrene to anthracene ranged from 1.21 in fish to 3.66 in meat, which suggest that the PAHs are from pyrogenic source. Similarly, the ratios of Flouranthene to Pyrene which ranged from 1.01 in plantain to 3.76 in fish also suggest pyrogenic source due to combustion and the benzo (a) anthracene to chrysene ranged from 0.03 in meat to 0.51 in plantain which equally suggested pyrogenic source. Thus, the relatively high concentration of PAHs in the roasted plantain and meat may be attributed to the smoking process.