fruit in secondary questions

[Huba Huba]

I fermented 3 gallons of a traditional, OG 1.092, FG 1.004, ABV 11.5% and used RC212. I mixed 8 lbs of strawberries and 2 lbs of bananas, and enough honey to make SG 1.088, this amounted to over 1 gallon volume, I also added K meta and pectinase (12+ hours apart). 36 hours later I then racked 2 gallons of the trad onto this mixture. So I have diluted my ABV to about 7%. After 36 hours it is barely bubbling and I would like my ending ABV to be over 10%. This is the first time I have added this much fruit into the secondary.
I realize perhaps I should have made the traditional to a higher alcohol content to compensate for the dilution, but evidently not that smart. When I realized what I had (failed) to do I added the honey to the fruit to hopefully ferment back close to my original ABV.
Should I add nutrients or oxygen or just wait and see what happens? Do you count on renewed fermentation after adding fruit to the secondary, should you rack and add fruit before it reaches FG? Do you plan on the dilution and ferment to a higher ABV to start?

 

[Rice_Guy]

Barely bubbling is fermenting. Oxygen will help and later on when nitrogen has been used nutrients help.
ALWAYS add nitrogen, and with a mead I encourage yeast rehydration nutrients > Fermaid O > Fermaid K at a third. ,,,, or other organic nitrogen ,,,, honey is a desert
oxygen, some mead makers/ white wine makers rack at 1.050ish to mix some air in and then put under air lock at that point.

 

[Huba Huba]

Thank you for your reply.
How would you calculate nutrient requirements? The two gallons of traditional mead was finished fermenting, so would you calculate based on the one gallon of fruit? I assumed there would be enough nitrogen/nutrient in the fruit to finish. After mixingi have 3 gallons, the SG was 1.037, TOSNA calculator says add no nutrients besides the Goferm needed to hydrate the yeast, I did not pitch additional yeast.

 

[Rice_Guy]

@Huba Huba , I missed that the two gallons was finished before the additions started. What happened when? What nutrients? If the calculator says you are OK you ought to be. Conceptually this is “step addition“ of sugar. Oxygenating this far into the process sounds like you would generate flavor issues.

OK my bias, you just added a slug of sugar , , and UC Davis says;
21 Brix should have 200mg nitrogen per liter
23 Brix should have 250mg nitrogen per liter
25 Brix should have 300mg nitrogen per liter
27 Brix should have 350mg nitrogen per liter
I would run the calculator again on just the one gallon of added fruit plus honey. IF it says it is OK, My tendency would be to thumb my noise at the calculator and add an organic nitrogen anyway

An interesting problem.

 

[Raptor99]

Your trad mead was fermented dry to about 11.5% ABV. The new 1 gal fruit must had OG 1.088, which would produce about 12% ABV if it fermented dry. So the potential ABV of the mixture (2 gals trad + 1 gal fruit must) would be a little more than 11.6%.

Do SG readings on consecutive days indicate that it is still fermenting?

Most mead makers don't add any more nutrients after 1/3 or 1/2 of the sugar is consumed. The yeast need nitrogen to reproduce, but not to ferment sugar. Since 2/3 of your new total volume has already fermented dry, about 2/3 of the total sugar has been consumed. Why would the yeast need any more nutrients at this point?

But a key question is whether the trad mead had any remaining viable yeast cells. How long ago did that finish fermenting? If you have reason to believe that the yeast from the trad mead were all dead, then this is like starting fresh with new yeast. You OG for this new 3-gallon mixture is probably something like (0.66 * 1.004) + (0.33 * 1.088) = 1.022. If you treat this like starting again with the 3-gallon batch, you could use OG 1.022 to calculate the amount of nutrients to add.

I'd be interested to see what others have to say about this.

 

[Huba Huba]

Thanks guys, right or wrong I added 3g Fermaid O yesterday evening and this morning it was going good. Degased a couple of times to manage the fruit cap, hopefully I won’t introduce to much oxygen. Not planning on any additional nutrients, but will see how things progress.
in the future I think I will stick with fruit in the primary or add it before fermentation completes.