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Victor E. Balderas-Hernández José T. Ornelas-Salas Ana P. Barba de la Rosa 《Journal of environmental science and health. Part. B》2020,55(2):148-154
AbstractThe presence of diethyl-phthalate (DEP), dibutyl-phthalate (DBP), butylbenzyl-phthalate (BBP), diethylhexyl-phthalate (DEHP) and diisononyl-phthalate (DINP) was determined in 295 tequila samples. They were grouped by age of maturation (white, aged, extra aged or ultra aged) and year of production (between 2013 and 2018). Gas Chromatography coupled with Mass Spectrometry was used for identification and quantification. The results showed that 65 samples (22% of the total) were phthalate free. DEP (0.13-0.27?mg/kg), BBP (0.05–2.91?mg/kg) and DINP (1.64–3.43?mg/kg) were detected in 11 (3.73%), 37 (12.54%) and 5 (1.69%) samples, respectively. But, these concentrations did not exceed the maximum permitted limits (MPL) of phthalates for alcoholic beverages. DBP (0.01–2.20?mg/kg) and DEHP (0.03–4.64?mg/kg) were detected in 96 (32.54%) and 224 (75.93%) samples, from them only 10 (3.39%) and 15 (5.08%) samples, respectively, exceeded the MPL for alcoholic beverages and they were few tequilas produced in the year 2014 or before. DEHP was the most frequent phthalate found in tequila and observed DEHP concentrations were 2-times higher in ultra aged tequilas compared to those in white tequilas. We concluded that all tequilas produced in 2015 and after, satisfied the international standards for these compounds. 相似文献
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精酒废醪液静置冷却后直接回用于酒精生产,按回用40m^3/d计,可减少COD排放约4000kg/d,并能取得一定的社会效益和经济效益。 相似文献
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农作物秸秆结构复杂,酸化效果可能与传统糖类物料不一致。为方便考察纤维素类物料厌氧酸化效果,文章选取成分相对单一的滤纸为原料,考察了酶活浓度、反应时间、酵母菌接种量(F/M)等因素对纤维素经纤维素酶和酵母菌联合作用后的乙醇、乙酸产量的影响,及对厌氧发酵过程的影响分析。结果表明,当纤维素酶单独作用时,酶活浓度120 U/g、温度50℃、pH值4.8、水解24 h时可获得最大葡萄糖产率:73.7 mg/g(转化率为24.9%);纤维素酶和酵母菌分步糖化发酵(separate hydrolysis and fermentation,SHF)工艺中,F/M值为2:1、反应96 h可得最大乙醇产率:119.3 mg/g(转化率为42%);纤维素酶和酵母菌同步糖化发酵(simultaneous saccharification andfermentation,SSF)工艺中,F/M值为1:2、反应120 h得到最大乙醇产率:396.0 mg/g(转化率为58.2%)。F/M值为2:1、反应120 h时,SSF工艺比SHF工艺的乙醇产量提高了34.91%。 相似文献
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Shawky M. Dagher Ziad K. Hawi Nasri S. Kawar 《Journal of environmental science and health. Part. B》2013,48(5):849-858
Abstract Wine and Arak, the national alcoholic drink in Lebanon, were prepared from grape juice fortified with fenitrothion to a concentration of 20ppm. Samples of the 11 fractions produced by the fermentation and distillation steps were analyzed for fenitrothion residues using gas chromatography (GC) and enzyme‐linked immunosorbent assay (ELISA). Results of residue analyses showed that the two techniques were highly correlated (r = 0.978) and indicated that fenitrothion was stable during the fermentation steps but not during distillation. The clarified wine 35 days later contained about 85% (15.3 ppm) of the fenitrothion concentration found in the juice as determined by GC analysis. Arak was prepared by a two‐steps distillation of the clarified wine. The alcohol distillate and undistilled fraction from the first distillation contained 2.5 ppm and 5.8 ppm of fenitrothion, respectively. No fenitrothion residues were detected by both techniques in the four fractions collected from the second distillation step. 相似文献
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Nasri S. Kawar Shawky M. Dagher 《Journal of environmental science and health. Part. B》2013,48(3):199-210
Abstract Arak, the national alcoholic drink in Lebanon, was prepared from grapes to which either DDT or parathion had been added. Samples of the nine fractions produced from the fermentation and distillation steps were analyzed for DDT and parathion and their respective metabolites. DDT degraded to DDD during the fermentation step resulting in a sharp decrease in DDT level. The two distillation steps contributed to a further decrease in the DDT level so that the final product contained less than 2% of the amount found in the fresh grape juice. Although the concentration of DDD increased sharply during fermentation, it also decreased to a negligible level during the subsequent distillation procedure. Parathion was more stable than DDT during the fermentation and first distillation steps. However, the second distillation process caused a share decline in its level and the Arak contained only about 6% of the residues present in the fresh juice, paranitrophenol being the only metabolite detected. 相似文献
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Nasri S. Kawar Yutaka Iwata Margarete E. Düsch Francis A. Gunther 《Journal of environmental science and health. Part. B》2013,48(5):505-513
Abstract Dialifor and methidathion were added to diluted “Zinfandel”; grape concentrate at 25 ppm and dimethoate at 1.0 and 25 ppm prior to fermentation with Saccharomyces cerevisiae. The finished wine 56 days later contained 10% (2.5 ppm) of the dialifor, 46% (12 ppm) of the methidathion and 85% (21 and 0.98 ppm) of the dimethoate added to the grape must. Residues in wine stored at 24°C dissipated by hydrolysis; half‐lives in wine were 7 days for dialifor and methidathion and 30 days for dimethoate. Residues were unchanged in wine in frozen storage for one year. Analysis of seven commercial wines for dimethoate indicated less than 0.03 ppm dimethoate was present; identity could not be confirmed by thin‐layer chromatography at this level. 相似文献