Faculty of Engineering, Department of Food Engineering, Akdeniz University, Antalya 07058, Turkey.
Bioresour Technol. 2010 Jul;101(14):5290-6. doi: 10.1016/j.biortech.2010.01.146. Epub 2010 Mar 1.
Carob has been widely grown in the Mediterranean region for a long time. It has been regarded as only a forest tree and has been neglected for other economical benefits. However, in recent years, this fruit has gained attention for several applications. As petroleum has become depleted, renewable energy production has started to gain attention all over the world; including the production of ethanol from underutilized agricultural products such as carob. In this project, the optimum extraction conditions were determined for the carob fruit by using the response surface design method. The obtained extract was utilized for production of ethanol by using suspended Saccharomyces cerevisiae fermentation. The effect of various fermentation parameters such as pH, media content and inoculum size were evaluated for ethanol fermentation in carob extract. Also, in order to determine economically appropriate nitrogen sources, four different nitrogen sources were evaluated. The optimum extraction condition for carob extract was determined to be 80 degrees C, 2h in 1:4 dilution rate (fruit: water ratio) according to the result of response surface analysis (115.3g/L). When the fermentation with pH at 5.5 was applied, the final ethanol concentration and production rates were 42.6g/L and 3.37 g/L/h, respectively, which were higher than using an uncontrolled pH. Among inoculum sizes of 1%, 3%, and 5%, 3% was determined as the best inoculum size. The maximum production rate and final ethanol concentration were 3.48 g/L/h and 44.51%, respectively, with an alternative nitrogen source of meat-bone meal. Overall, this study suggested that carob extract can be utilized for production of ethanol in order to meet the demands of renewable energy.
角豆在很长一段时间里在地中海地区被广泛种植。它一直被认为只是一种森林树木，其他经济利益被忽视了。然而，近年来，这种水果因其多种应用而受到关注。随着石油的枯竭，可再生能源的生产开始在全世界引起关注；包括利用未充分利用的农产品（如角豆）生产乙醇。在这个项目中，通过响应面设计方法确定了角豆果实的最佳提取条件。通过使用悬浮酿酒酵母发酵，利用获得的提取物生产乙醇。评估了各种发酵参数（如 pH 值、培养基含量和接种物大小）对角豆提取物中乙醇发酵的影响。此外，为了确定经济上合适的氮源，评估了四种不同的氮源。根据响应面分析的结果（115.3g/L），角豆提取物的最佳提取条件确定为 80°C、2h、稀释率为 1:4（果实与水的比例）。当应用 pH 值为 5.5 的发酵时，最终乙醇浓度和生产速率分别为 42.6g/L 和 3.37 g/L/h，高于使用未控制 pH 值的情况。在 1%、3%和 5%的接种物大小中，3%被确定为最佳接种物大小。使用肉骨粉作为替代氮源时，最大生产速率和最终乙醇浓度分别为 3.48 g/L/h 和 44.51%。总的来说，这项研究表明，角豆提取物可以用于生产乙醇，以满足可再生能源的需求。
