Ice cider fermentation slowing too much?

[Scott Harring]

Looking for advice on my first try at Ice cider.  Initial juice cryoconcentrated to 1.152 and a TA of 17.3.  Pitched 71B yeast after making a starter with similar concentrated juice.  Fermentation started 9/27 in a 55F freezer.   It was dropping 1 gravity point a day for first two months, but have seen things slow substantially the past month.  So far I’ve increased the temp to 65 F and added half dose Fermaid O (0.75 g/gal).  Right now SG is 1.095 and TA 17.2.  Fermentation speed has slowed to 1 point drop every 5 days despite initial interventions.  And it continues to slow as it progresses.

Juice was from an unfertilized apple collector’s orchard, mix of desert and heritage apples.  No sulfates in this batch.  Haven’t racked at all yet. 

Deceleration of my fermentation speed makes me wonder if I’m about to get stuck at a final gravity higher than optimal.  Wondering if I should further intervene now to speed things up a little? And if so, what to do?  Raise temp further, more femaid-0, repatch fresh yeast, or just do nothing and see what happens?

Taste wise I’m happy with how things are going.  The high acidity still impacts the pallet, but flavor is otherwise quite nice. 

I did another batch about a month later with some desert apples form a fertilized orchard.  Similar initial profile (SG 1.153 and TA 16.4).  That one is at 1.103 and dropping a point every two days currently.  I’m planning to let that batch continue to do its own thing for now.

Appreciate it,

Scott

[Claude Jolicoeur]

You really have higi initial concentration there. I usually do mine at around 1.135 SG.

As you have high SG, it is normal to also have high acidity, and you will probably also want higher final gravity - probably 1.075 would be good for the acidity.

If now at 1.095, you'd have 20 more points to go - so 100 days at current speed. I'd let it go, and if speed decreases more, I'd add a bit more nutrients - but not too much!