Flow injection determination of readily assimilable nitrogen compounds during vinification
نویسندگان
چکیده
منابع مشابه
Flow injection determination of readily assimilable nitrogen compounds during vinification.
A flow injection method for the determination of readily assimilable nitrogen (r.a.n.), i.e. ammonium and aminated nitrogen, is reported. The difference in pH of the sample in the presence and absence of formaldehyde, which blocks the amino function, provides the value of r.a.n. by monitoring the changes in absorbance of bromothymol blue at 616 nm. The detection and quantification limits are 10...
متن کاملA flow-injection system coupled to a micro-guard cartridge for monitoring a vinification process.
The present paper describes a flow-injection system coupled to a Micro-Guard cartridge and a miniaturized optical CCD detection system used to monitor the sugars (glucose/fructose) and ethanol content during alcoholic fermentation. The carrier stream (mobile phase) is composed of an aqueous sulfuric acid solution. The flow parameters were studied in order to obtain a good resolution and a wide ...
متن کاملImpact of assimilable nitrogen availability in glucose uptake kinetics in Saccharomyces cerevisiae during alcoholic fermentation
BACKGROUND The expression and activity of the different Saccharomyces cerevisiae hexose uptake systems (Hxt) and the kinetics of glucose uptake are considered essential to industrial alcoholic fermentation performance. However, the dynamics of glucose uptake kinetics during the different stages of fermentation, depending on glucose and nitrogen availability, is very poorly characterized. The ob...
متن کاملDetermination of ethanol using flow injection enthalpimetry.
A flow injection enthalpimetric method for the determination of ethanol in fuel-grade ethanol, based on the heat of dilution of ethanol, is described. The accuracy and precision were 0.05% of ethanol; interferences by several substances are discussed. A similar procedure was also applied to the determination of ethanol in wines and spirits after distillation, yielding a precision of 0.0%0.1% of...
متن کاملReadily accessible chiral at nitrogen cage structures.
The reaction of glycine-N-methyl amide with paraformaldehyde in the presence of ytterbium triflate (1 mol%) leads to a novel cage structure 6 which is chiral at nitrogen. Single crystal X-ray analysis and DFT calculations suggest this cage structure is rigid and adopts a single low energy conformation. Use of single enantiomer α-amino amides results in two diastereomeric tertiary amines that di...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Analyst
سال: 2002
ISSN: 0003-2654,1364-5528
DOI: 10.1039/b110686b