nb0s wrote:BCarter wrote:DAP will boost nitrogen better than TPW will. That's a chemical fact, or wineries around would be adding tomato paste left, right and centre. This is due to the ease of DAP to be assimilated by yeast cells, as opposed to relying on enzymes to break down nitrogen present in the tomato paste into more inorganic forms. ... Tomato paste however has the addition of micronutrients which will also aid in the positive growth of yeast and hence, fermentation.
Your post is quite correct. However there is a world of difference between the distilling world and the wine world. I mean who wants to drink a pink wine? :D This is a distillers forum and a TPW is always going to be distilled. Best practice might suggest the addition of DAP mid ferment but the KISS principle asks. "Is it really necessary?" TPWs that aim for only 10-11% ABV leave the yeast in such good shape and numbers that successive ferments may be done on the lees of these low ABV washes without the addition of more yeast.
Like I said, DAP is incredibly useful for distilling to avoid volatile H2S and acetaldehyde which greatly decreases the quality of distillation. It is completely necessary to avoid these aromas that occur due to a struggling ferment, no matter what the end alcohol is.
Unless, you don't really care about the quality of the distillation, in which case, go right ahead. If you arent bothered about nuances in congeners left over in the distillation, then hey, anyway you can get the ferment dry, do it.
The question of the yeast being in shape at the end of a ferment is not the question. Lees is lees...you will almost always be able to ferment from lees without much trouble. There are millions of active cells/ml in lees. Only issue will be the mutagenic nature of yeast through consecutive ferments.
This is a little off topic, sorry, but if you want a reproducible result, for distillation that requires congeners to be passed through (not the case for TPWs), you'll need the correct spread of volatiles present in the fermented wash. For this, you'll need a consistent strain of yeast that has low mutagenic properties. This is due to the whole process of fermentation involving 1000s of generations of yeast cells dividing/budding.
Sorry to be particular on details, I'm just sharing my knowledge of fermentation. I'd love to see people producing commercial quality products in their own homes...I'm just sharing the considerations that us commercial boys have...20,000 to 50,000L of product I deal with goes to distillation, I need to make sure I'm doing the best I can to ensure a good end product with minimal amelioration.