Yeast Assimilable Nitrogen (organic and inorganic nitrogen)
Yeast Assimilable Nitrogen (YAN) is a fundamental parameter to manage correctly the alcoholic fermentation. It is constituted by two components: the inorganic nitrogen present in must as ammonium ion (NH4+) and organic nitrogen constituted by α -amino nitrogen of amino acids.
Inorganic nitrogen (ammonium) is determined with the enzymatic way whereas organic nitrogen is determined with the o-phthalaldehyde method.
Method
Sample treatment
If necessary, the sample shall be degassed using the specific ultrasonic bath (code 222062). In case of tests performed on must, the sample shall be centrifuged (code 222061) or filtered (code 300210).
Principle of the test
Organic nitrogen test
The α-amino nitrogen reacts, in presence of N-acetyl-L-cysteine, with the o-phthalaldehyde to form an isoindolic derivative. The difference in absorbance, measured at 366 nm (end-point) is correlated with the amount of organic nitrogen expressed as mg/L of N.
...
Inorganic nitrogen test
The ammonium reacts by enzimatic path-way with NADH and α-ketoglutarate to give NAD+ and glutamate. The decrease in absorbance of the solution of NADH, measured at 366 nm (end-point), is proportional to the amount of ammonium nitrogen in the sample.
...
Calibration curve
The calibration curve of CDR CiderLab for the analysis of Yeast Assimilable Nitrogen Organic in must, obtained using reference methods, confirms the excellent linearity of the system over the whole testing range.
...
The calibration curve of CDR CiderLab for the analysis of Yeast Assimilable Nitrogen Inorganic in must, obtained using reference methods, confirms the excellent linearity of the system over the whole testing range.
...
Reagent test Kits
Please note: Organic (*301430, *301435) and Inorganic Nitrogen (*301440, *301445) kits must be used together.
Measuring range
| Analyses | Measuring range | Resolution | Repeatability |
|---|
The Analyzers for process and quality control in cider production
CDR CiderLab
Complete analysis panel, supplied already configured
Up to 16 determinations simultaneously
Possibility of carrying out analyses of the same sample
Integrated printer
Full connections (LAN - USB - Bluetooth barcode/QR code reader)
CDR CiderLab Jr
Partial analysis panel, customisable configuration
Up to 3 determinations simultaneously
Wireless connection to external printer
USB connections