However, one simple formula that I have tested and seems to be a reasonable formula is the one given at the website of the UK yeast producer DCL at <a href="http://www.dclyeast.co.uk/www.dclyeast.co.uk/DCL_Main/main_tech/tech_dried.html,">http://www.dclyeast.co.uk/www.dclyeast.co.uk/DCL_Main/main_tech/tech_dried.html,</a> specifically, The quantity needed is mainly determined by the recipe and process used and on local climatic conditions.