Some additional info re just adding DAP alone and also sheads some light on why SNA ratios being used by award winning meadmakers are changing over the last 5 years.
DAP is a simple and non-organic source of nitrogen and it does not offer any additional nutrition. DAP shouldn't be thought of as any more than a supplement as a small part of a complete nutrient scheme when dealin with low nitrogen musts. It will makeyeast grow and reproduce more cells, but it does not really feed them.
"I've made this analogy before, but if you consider Fermaid-K to be a complete and balanced meal with high levels of vitamins, minerals and
natural sugars, then DAP would be like a glass of soda, offering quick energy but no nutritional value.
Fermentations that are sluggish and producing H2S due to a lack of nutrients will not benefit from a DAP addition. In fact, adding DAP will increase the number of starving cells and cause a population explosion in a nutrient void gradient. Fermaid K, which does contain a small amount of DAP is a balanced and complete nutrient and as such, there is little reason to dose with DAP as well."
quoted from Paul Bakulic (Got Mead partner and forum administrator - a true expert on meads according to Curt Stock)
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