YAN is measured in two steps using the Thermo Fisher Gallery discrete analyser, as total nitrogen cannot be quantified by measuring only ammonia. The first step involves measurement of alpha amino nitrogen. It does not detect secondary acids such as hydroxy proline or proline (which is not utilised by yeast), nor does it detect ammonia. The second step determines the amount of ammonia present. The two measurements together enable YAN to be calculated.
Samples must be submitted for this analysis in plastic containers and frozen prior to despatch. Samples that have commenced fermentation will not give accurate results.
For further information on yeast assimilable nitrogen, please refer to this article (Weeks and Henschke 1999) and this webpage.
Prices per analysis | |||
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Analysis | Per Sample (excluding GST) | Volume required | Target response time |
YAN (Yeast assimilable nitrogen including alpha amino nitrogen and ammonia) | $36.75 | 10 mL of juice | 24 hrs after receipt of samples |
Other relevant price combinations see Grape and colour analysis for more information:
Prices per analysis | |||
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Analysis | Per Sample (excluding GST) | Volume required | Target response time |
Basic Vintage Panel (Brix or Baumé / pH/ Titratable acidity) | $25.20 | 200 grams of berries or 50 mL of juice | 24 hrs after receipt of samples |
White/Red Grape Vintage Panel (Brix or Baumé / pH/ Titratable acidity /YAN) | $57.75 |
For more information, please contact AWRI Commercial Services on (08) 8313 6600 or commercialservices@awri.com.au