Fermentation Schedule

[Jenks829]

I have 300 pounds of Merlot grapes in a 78 gallon fermenter. The fermenter is not quite half full. I pitched 6 packs of EC-1118 on Monday evening. The starting gravity was 25.5 Brix. Now, 7 days later, it reads 22 Brix with a hydrometer. Does this seem slow to anyone else?

I just added 14 grams of yeast nutrient with plans on adding another 10 grams when the gravity is under 10 Brix.

The must smells fine, there seems to be yeast activity with the must generating heat, there is a cap formation and some "snap and crackle" sounds.

What say you?

 

[JasonH]

Sounds ok to me. A large batch like that would surely take a long time to get started. Did you make a yeast starter to help the yeast get going? I wouldn't worry about a "fermentation schedule" as every batch has its own schedule whether we like it or not. As long as your gravity is decreasing I wouldn't worry too much.

 

[Wade E]

Sounds a little slow to me, whats the temp and what was it when you pitched the yeast? Did you sulfite this batch and how much did you use?

 

[winemaker_3352]

I agree with wade - it does sound a little sluggish. I would think after 7 days it would be lower that 22 brix.

 

[Jenks829]

The temp when I pitched the yeast was just over 60F (about 62 or 63). I did not make a starter. I did use 6 packs (30 grams) of EC-1118.

The temperature now is 68F. This is higher than the ambient temp in the garage which is about 60F.

I did sulfate with 4 g of Potassium Metabisulfate powder when I first brought the crushed grapes home. I was aiming for 25-30 ppm.

I do not have a pH measurment. The TA was slightly high at 0.9%

 

[JohnT]

The temp when I pitched the yeast was just over 60F (about 62 or 63). I did not make a starter. I did use 6 packs (30 grams) of EC-1118.

The temperature now is 68F. This is higher than the ambient temp in the garage which is about 60F.

I did sulfate with 4 g of Potassium Metabisulfate powder when I first brought the crushed grapes home. I was aiming for 25-30 ppm.

I do not have a pH measurment. The TA was slightly high at 0.9%

1) This could explain things. The wine could be too cold. Try bringing it up to about 70.

2) how long did you wait between adding the Potassium Metabisulfite and adding the yeast? if you added them together, then you could have killed the yeast (with the k-meta).

3) have you been doing any punch downs? Was the yeast mixed into the must?

4) 22 brix seems rather low for merlot. I would think that the acid level is higher rather than too low. I would test this and adjust after fermentation has completed.

 

[Jenks829]

1) This could explain things. The wine could be too cold. Try bringing it up to about 70.

I will try this.

2) how long did you wait between adding the Potassium Metabisulfite and adding the yeast? if you added them together, then you could have killed the yeast (with the k-meta).

I pitched the yeast 24 hours after adding K-meta.

3) have you been doing any punch downs? Was the yeast mixed into the must?

I did not mix or stir the yeast for 24 hours after sprinkling yeast on the must; and when I did, it was a gentle rake to ensure all the yeast had a good aerobic stage. I've been punching down twice daily for the last 5 days (since Wednesday; pitched on Monday)

4) 22 brix seems rather low for merlot. I would think that the acid level is higher rather than too low. I would test this and adjust after fermentation has completed.

I feel this is high also. I was not planning on making any adjustments now. I just wanted to give all the info I had.

 

[JohnT]

Sounds like you did everything right. Try upping the temp and let us know how you make out.

 

[almarques7]

that temperature is very low for 7 days in. wrap the fermenter with blankets maybe bring in a space heater... once it really starts bubbling and that cap is moving it should come up to around 80 or 90 degrees... try to warm it up and you should be fine

 

[Jenks829]

that temperature is very low for 7 days in. wrap the fermenter with blankets maybe bring in a space heater... once it really starts bubbling and that cap is moving it should come up to around 80 or 90 degrees... try to warm it up and you should be fine

I've done the best I can considering the recent dip in temperature here.

I have the fermenters sitting on 4x4 pieces of wood to minimize heat loss to the concrete floor. They have been this way since the start.

They are arranged side-by-side with a space heater between them and a sleeping bag opened up and placed over top and draped down the back in an attempt to keep the heat produced by the space heater trapped close to the fermenters.

The temps in both fermenters (measured in the cap) is 70F-72F

The Merlot was down to 19 Brix this morning. Yeast was pitched on Monday 10-25 at a starting gravity of 25.5 Brix so I've only advanced this about 6.5 Brix in 9 days.

I put a call in to my local homebrew shop. They believe a fix will be to use a yeast nutrient with more nitrogen. I have mixed in 14 grams of Fermax on Sunday.

 

[Rock]

The temp when I pitched the yeast was just over 60F (about 62 or 63). I did not make a starter. I did use 6 packs (30 grams) of EC-1118.

The temperature now is 68F. This is higher than the ambient temp in the garage which is about 60F.

I did sulfate with 4 g of Potassium Metabisulfate powder when I first brought the crushed grapes home. I was aiming for 25-30 ppm.

I do not have a pH measurment. The TA was slightly high at 0.9%

How much does 4g of p-meta add up too?Like teaspoons?I only go by teaspoons so i would do like 1/2 teaspoon per 100lbs will stunt the wild yeast.

 

[Jenks829]

How much does 4g of p-meta add up too?Like teaspoons?I only go by teaspoons so i would do like 1/2 teaspoon per 100lbs will stunt the wild yeast.

Gram is a unit of mass. Teaspoon is a unit of volume. To be accurate we would need to know the density of the potassium metabisulfite. If we make the approximation that the potassium metabisulfite powder has about the same density of granulated sugar we could estimate that 1 teaspoon is about 4.2 grams.

I treated with 4 grams of potassium metabisulfite in 300 pounds of crushed grapes. So that is about 1 teaspoon.

 

[Jenks829]

I just got off the phone with one of the wine guru's from my local shop. He says not to worry so long as fermentation is progressing. He has the same situation with his Washington Merlot grapes.

One of his recommendations was to take a sample of must (3 gallons) in a separate container and place in warm bath to raise temp to 80F. Once that really gets going, pour over top (do not mix in) the primary fermenter and see if that helps wine take off.

I may do this tonight. It does help ease the mind knowing that this guy has a slow fermentation and he is not worried.

 

[Jenks829]

Temp seems to have helped a lot. When I got home last night, the temp of the Merlot must was 78F and the gravity reading was 15.5 Brix. This is down about 4 Brix in 24 hours.

I have another 300lb batch of Cabernet which is about a week behind the Merlot. It started at 23 Brix and is below 20 now with a must temp of 80F

 

[almarques7]

just needed a little jump start, cheers

 

[Sen]

It would be nice to have an ideal fermentation schedule to accompany the recipe. I think brewers know that the actual schedule may have to be modified to fit current conditions. The progress tracking and perhaps automatic schedule adjustment would be nice.