The YAN calculator is a quick and easy way to determine type, amount, and schedule of nutrient additions for your must, and was developed by Willem Wyngaards.
The calculator uses the starting Brix of your must, type of yeast planned, and existing YAN in your must, to calculate additional nutrients needed in order to maintain a healthy fermentation. If you do not know the YAN (yeast available nitrogen) of your juice then you will need to make a conservative guess. Read the article adding nitrogen to fermentations for more information on YAN in winemaking.
The calculator is an Excel file in xlsx format (Excel 2010 and later).
Download: Wyngaard Must Calculations
*October 2022 version has nutrient additions based on the latest nutrient requirements from the Scott Labs.
*October 2021 version – Amended nutrient distribution table and also adjusted the yield factors so that it is based on the total grape weight and not de-stemmed weight.
* August 2015 version — Additional calculators added for chaptalization (adding sugar to increase starting Brix) and amelioration (adding water to reduce Brix). Also includes estimators of volume of crush (reds) or juice (whites) when the product arrives in 6 gallon pails based on freeboard.
* April 2015 version— The yeast dropdown menu (which got dropped somehow) is back as it is required for YAN calculations dependent on yeast type.
* Sept 2016 version— New more expanded calculator from Willem. Has multiple pages for other aspects of winemaking.
* Sept 2016 version— Expanded version (above) was replaced with single page version as the expanded version was supplied by Willem by mistake.
* Sept 2019 version— New expanded calculator version supplied by Willem incorporating latest Scott Labs nutrient factors.
* August 2021 version – This version has been edited top to bottom with new calculators. Comments have been edited with new warnings and Fermaid O now adds 160 mgN/L. Yeast nutrient match the Scot Lab Handbook 2021 recommendations.