RESUMEN
In order to solve environmental problems resulting from ammonia released into the atmosphere, the emission of ammonia contamination from monosodium glutamate (MSG) production was quantitatively observed, and the relationships with relevant influencing factors (ammonium-N, nitrate/nitrite-N and pH) were statistically analyzed. The results indicated that the release of gaseous ammonia from MSG production including the treatment and discharge of wastewater was highly dependent on the technical processes utilised. The flux of ammonia released from the fermentation workshop was highest, up to 8.98 x 10(5) mg m(-3) min(-1), and the flux from the sugar-refining workshop was lowest, only 85.1 mg m(-3) min(-1). The release of gaseous ammonia during the whole MSG production was significantly proportional to the concentration of ammonium-N in the discharged solution, and exponentially proportional to the concentrations of nitrate-nitrogen and nitrite-nitrogen in the discharged solution. Although there was no linear relationship between the flux of ammonia released during the whole MSG production and pH values in the discharged solution, pH was significantly related to the flux of ammonia released during the treatment and discharge of wastewater.
Asunto(s)
Contaminantes Atmosféricos/análisis , Amoníaco/análisis , Industria Química , Residuos Industriales/análisis , Glutamato de Sodio/síntesis química , Contaminantes Atmosféricos/química , Contaminación del Aire/prevención & control , Amoníaco/química , China , Monitoreo del Ambiente , Concentración de Iones de Hidrógeno , Nitratos/química , Nitritos/química , Glutamato de Sodio/químicaRESUMEN
In 1907 Kikunae Ikeda, a professor at the Tokyo Imperial University, began his research to identify the umami component in kelp. Within a year, he had succeeded in isolating, purifying, and identifying the principal component of umami and quickly obtained a production patent. In 1909 Saburosuke Suzuki, an entrepreneur, and Ikeda began the industrial production of monosodium l-glutamate (MSG). The first industrial production process was an extraction method in which vegetable proteins were treated with hydrochloric acid to disrupt peptide bonds. l-Glutamic acid hydrochloride was then isolated from this material and purified as MSG. Initial production of MSG was limited because of the technical drawbacks of this method. Better methods did not emerge until the 1950s. One of these was direct chemical synthesis, which was used from 1962 to 1973. In this procedure, acrylonitrile was the starting material, and optical resolution of dl-glutamic acid was achieved by preferential crystallization. In 1956 a direct fermentation method to produce glutamate was introduced. The advantages of the fermentation method (eg, reduction of production costs and environmental load) were large enough to cause all glutamate manufacturers to shift to fermentation. Today, total world production of MSG by fermentation is estimated to be 2 million tons/y (2 billion kg/y). However, future production growth will likely require further innovation.
Asunto(s)
Aromatizantes/historia , Glutamatos/historia , Glutamato de Sodio/historia , Bacterias/metabolismo , Fermentación , Aromatizantes/síntesis química , Aromatizantes/aislamiento & purificación , Industria de Alimentos/historia , Glutamatos/síntesis química , Glutamatos/aislamiento & purificación , Historia del Siglo XX , Historia del Siglo XXI , Extractos Vegetales/síntesis química , Extractos Vegetales/historia , Extractos Vegetales/aislamiento & purificación , Glutamato de Sodio/síntesis química , Glutamato de Sodio/aislamiento & purificación , TokioRESUMEN
Fluxes of ammonia contamination from production of monosodium glutamate (MSG) were quantitatively observed and relationships with some important influencing factors were statistically analyzed. The study indicates that there is a big difference in the release of ammonia at each step of MSG production including sewage treatment, depending on technical processes. The flux of ammonia released in the process of fermentation was highest, up to 880 mg x (L x min)(-1), and that in the process of refining sugar was lowest, only 0.07 mg x (L x min)(-1). Fluxes of NH3 emission during the whole process of MSG production are significantly related with the concentration of ammonium-nitrogen (NH4+ -N) in discharged solution linearly, and with concentrations of nitrate-nitrogen (NO3- -N) including nitrite-nitrogen (NO2- -N) in discharged solution exponentially. Although there is no linear relationship between fluxes of NH3 emission during the whole process of MSG production and pH values in discharged solution, it is significantly related with fluxes of NH3 emission during the process of sewage treatment.