The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic appl...The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39<sup>a</sup> for the initial crude oil to 128.53<sup>d</sup> for the oil treated with 3% activated carbon versus 187.59<sup>a</sup> for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99<sup>b</sup>). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67<sup>b</sup> against 79.04<sup>a</sup> for the oil filtered with 3% activated carbon, 86.33<sup>a</sup> for the crude oil and 86.46<sup>a</sup> for the oil filtered on cloths. Finally, the oil sample treated with 5% activated carbon had the clearest clarity than the other samples with a clarity (L) equal to 97.98<sup>c</sup> against 95.63<sup>d</sup> for the oil treated with 3% carbon and 94.99<sup>b</sup> for the oil filtered on filter cloths. According to the results obtained, the experimental device made it possible to obtain a clearer baobab oil with a low brown index, thus improving the sensory quality of the oil.展开更多
以实验室自酿草莓酒为试材,研究皂土、聚乙烯吡咯烷酮(polyvinylpyrrolidone,PVPP)、壳聚糖、蛋清粉及明胶5种不同澄清剂对酒样澄清效果、理化指标、挥发性成分及感官品质的影响。结果表明,澄清处理后草莓酒的透光率均显著提高(P<0.0...以实验室自酿草莓酒为试材,研究皂土、聚乙烯吡咯烷酮(polyvinylpyrrolidone,PVPP)、壳聚糖、蛋清粉及明胶5种不同澄清剂对酒样澄清效果、理化指标、挥发性成分及感官品质的影响。结果表明,澄清处理后草莓酒的透光率均显著提高(P<0.05),提高了8.37%~25.53%;各酒样的酒精体积分数、总酸含量、pH值等基础理化指标变化较小,但总酚(10.26%~27.75%)、总黄酮(6.43%~18.88%)及花色苷含量(9.51%~43.04%)均显著降低。采用顶空固相微萃取结合气相色谱-质谱(headspace solid-phase micro-extraction and gas chromatography-mass spectrometry,HS-SPME-GC-MS)技术检测其挥发性成分,共检测出69种挥发性香气化合物,包括42种酯类、16种醇类、5种酸类、8种萜烯类和6种醛酮及其他类物质,经下胶澄清处理后酒样中挥发性物质的种类和含量(11.51%~35.57%)均有所下降,其中0.2 g/L壳聚糖处理组对挥发性香气物质的影响较小;感官评价表明,0.2 g/L壳聚糖能更好地降低酒中的苦、涩味,与原酒颜色接近,香气更加平衡协调,感官品质高。综合评定0.2 g/L壳聚糖为草莓酒的最佳澄清方案,研究结果可为草莓酒的澄清生产提供数据支撑和技术参考。展开更多
文摘The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39<sup>a</sup> for the initial crude oil to 128.53<sup>d</sup> for the oil treated with 3% activated carbon versus 187.59<sup>a</sup> for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99<sup>b</sup>). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67<sup>b</sup> against 79.04<sup>a</sup> for the oil filtered with 3% activated carbon, 86.33<sup>a</sup> for the crude oil and 86.46<sup>a</sup> for the oil filtered on cloths. Finally, the oil sample treated with 5% activated carbon had the clearest clarity than the other samples with a clarity (L) equal to 97.98<sup>c</sup> against 95.63<sup>d</sup> for the oil treated with 3% carbon and 94.99<sup>b</sup> for the oil filtered on filter cloths. According to the results obtained, the experimental device made it possible to obtain a clearer baobab oil with a low brown index, thus improving the sensory quality of the oil.
文摘以实验室自酿草莓酒为试材,研究皂土、聚乙烯吡咯烷酮(polyvinylpyrrolidone,PVPP)、壳聚糖、蛋清粉及明胶5种不同澄清剂对酒样澄清效果、理化指标、挥发性成分及感官品质的影响。结果表明,澄清处理后草莓酒的透光率均显著提高(P<0.05),提高了8.37%~25.53%;各酒样的酒精体积分数、总酸含量、pH值等基础理化指标变化较小,但总酚(10.26%~27.75%)、总黄酮(6.43%~18.88%)及花色苷含量(9.51%~43.04%)均显著降低。采用顶空固相微萃取结合气相色谱-质谱(headspace solid-phase micro-extraction and gas chromatography-mass spectrometry,HS-SPME-GC-MS)技术检测其挥发性成分,共检测出69种挥发性香气化合物,包括42种酯类、16种醇类、5种酸类、8种萜烯类和6种醛酮及其他类物质,经下胶澄清处理后酒样中挥发性物质的种类和含量(11.51%~35.57%)均有所下降,其中0.2 g/L壳聚糖处理组对挥发性香气物质的影响较小;感官评价表明,0.2 g/L壳聚糖能更好地降低酒中的苦、涩味,与原酒颜色接近,香气更加平衡协调,感官品质高。综合评定0.2 g/L壳聚糖为草莓酒的最佳澄清方案,研究结果可为草莓酒的澄清生产提供数据支撑和技术参考。