Yeast Rehydration is good stuff

[winemaker81]

I'm curious about the starter status when the yeast run out of food? My typical starter is 8oz 100F h20, 1tsp GoFerm & 2tsp white table sugar. Like you, I've been starting the night b4 for next morning inoculation. My starters tend to go gangbusters for the first few hours with visible activity & froth on top buildup...but by morning have settled down with no apparent activity. That said....my starters always do a great job!

I currently add a LOT more sugar than that.

I've been updating my yeast starter post, and am currently up to 2 to 6 Tbsp sugar. I'm probably going to change that to 5 to 6 Tbsp, and that's for a starter that runs 12 to 14 hours.

The FWK Packet B is mostly sugar, and it's a goodly amount. However, last I recall FWK recommends a 24 hour period, so more sugar makes sense.

 

[Bmd2k1]

I currently add a LOT more sugar than that.

I've been updating my yeast starter post, and am currently up to 2 to 6 Tbsp sugar. I'm probably going to change that to 5 to 6 Tbsp, and that's for a starter that runs 12 to 14 hours.

The FWK Packet B is mostly sugar, and it's a goodly amount. However, last I recall FWK recommends a 24 hour period, so more sugar makes sense.

Well dang! I need to up my sugar -- lol. Appreciate the heads up ;-)

Cheers!

 

[winemaker81]

Well dang! I need to up my sugar -- lol. Appreciate the heads up ;-)

This has been a learning experience, trial-n-error, with an emphasis on error.

I learned some from reading, some from experimentation, and some from inference.

It just occurred to me to boil 1 cup water, stir 6 Tbsp sugar, let cool to room temperature, and check the SG. This is probably a useful data point.

 

[wineview]

I currently add a LOT more sugar than that.

I've been updating my yeast starter post, and am currently up to 2 to 6 Tbsp sugar. I'm probably going to change that to 5 to 6 Tbsp, and that's for a starter that runs 12 to 14 hours.

The FWK Packet B is mostly sugar, and it's a goodly amount. However, last I recall FWK recommends a 24 hour period, so more sugar makes sense.

5-6 Tbls. sugar in addition to Go Ferm? I’ve been using 1-2 tsp sugar with Go Ferm to get it going. Let sit for 20 minutes. Then add 1/3 volume of must or juice let sit for another 20 minutes. Depending on time restraints I may add another 1/3 volume of juice or must and let sit for another 20 minutes. By this time the starter and must is almost identical in temperature. At that point I pitch.

 

[Raptor99]

The amount of sugar you add depends on how long you want to keep it going. If you want to leave it overnight you need a lot more sugar. But you need nutrients as well. If the yeast run out of sugar they will go dormant again. But if the yeast run out of nutrients, they will produce off flavors.

I don't add sugar. I start with GoFerm, which includes sugar and nutrients. Once that gets going I add some of the must, which also contains both sugar and yeast nutrients.

 

[winemaker81]

5-6 Tbls. sugar in addition to Go Ferm? I’ve been using 1-2 tsp sugar with Go Ferm to get it going. Let sit for 20 minutes. Then add 1/3 volume of must or juice let sit for another 20 minutes. Depending on time restraints I may add another 1/3 volume of juice or must and let sit for another 20 minutes. By this time the starter and must is almost identical in temperature. At that point I pitch.

I don't use GoFerm. I use Fermax as my nutrient (have used it for years) so I add some of that to the starter.

Giving the yeast 12+ hours to reproduce generates a much larger initial colony when inoculating. I checked my notes -- since making the overnight starter I can smell fermentation within 6 hours of inoculation, and have smelled it in 3 hours. I may not see activity, but the nose knows.

I haven't tried adding the must to the starter. The method I use is wildly successful, so I have not seen a need to change.

 

[BarrelMonkey]

I've always used something like the Scottlabs protocol described above, with GoFerm and adding juice/must until temperature is within 10C/18F of the bulk juice/must. I typically pitch same day as making the starter.

I haven't tried adding the must to the starter. The method I use is wildly successful, so I have not seen a need to change.

Why mess with success! Though reportedly some yeast strains do better if allowed to grow in must before inoculation. From here (Assmanshausen yeast):

Good strain domination is obtained with AMH if the culture is allowed to develop in about 10% of the total must for about 8 hours before final inoculation.

(though the one time I used AMH for pinot noir I didn't wait that long or use that much must, but still had a textbook fermentation...)

 

[wineview]

I don't use GoFerm. I use Fermax as my nutrient (have used it for years) so I add some of that to the starter.

Giving the yeast 12+ hours to reproduce generates a much larger initial colony when inoculating. I checked my notes -- since making the overnight starter I can smell fermentation within 6 hours of inoculation, and have smelled it in 3 hours. I may not see activity, but the nose knows.

I haven't tried adding the must to the starter. The method I use is wildly successful, so I have not seen a need to

I use Fermax in my fermenting bucket. Do you happen to know the difference between Fermax and GoFerm?

 

[winemaker81]

I use Fermax in my fermenting bucket. Do you happen to know the difference between Fermax and GoFerm?

Not specifically. Last I checked, GoFerm was a lot more expensive.

 

[Garagista]

I guess I do things slightly different.

Since one cup of wine must contains around 60 grams of sugar at 25 Brix, I skip the sugar and ferment directly in must. One and 1/2 cup is equal to around 7 Tablespoons of sugar so I just add my go-ferm to 1.5 cups of 110 degree must, let it cool to 106 then add the yeast directly to that. Let is sit overnight. Like everyone here, it seems to work fine.

 

[winemaker81]

It's amazingly difficult to feel superior when everyone's solution also works.

All joking aside, it's good to know that we have many valid choices, although the plethora of choices may be confusing to beginners.

 

[Bmd2k1]

It's amazingly difficult to feel superior when everyone's solution also works.

All joking aside, it's good to know that we have many valid choices, although the plethora of choices may be confusing to beginners.

Where the heck is the "WMT Intern" when ya need em! To crank out some bench trials, collect data, chart the bell curve(s) & report back to the masses!

Cheers!

 

[Ohio Bob]

It just occurred to me to boil 1 cup water, stir 6 Tbsp sugar, let cool to room temperature, and check the SG. This is probably a useful data point.

Starting my Chilean Viognier today, thought I would weigh in the SG of the yeast starter.

A cup of water sounds like a lot for a 6g batch. I went with my process, 100ml of filtered water, 1 TBS of table sugar. That mixture measured 13 Brix on my refractometer.

I can see why you could go to 2 TBS, but not too much more than that. I’ll try to keep a close eye on the ferment, but since it’s a white wine, fermenting in my 60F cellar, the ferment hopefully will be slow.

 

[winemaker81]

Starting my Chilean Viognier today, thought I would weigh in the SG of the yeast starter.

A cup of water sounds like a lot for a 6g batch. I went with my process, 100ml of filtered water, 1 TBS of table sugar. That mixture measured 13 Brix on my refractometer.

I can see why you could go to 2 TBS, but not too much more than that. I’ll try to keep a close eye on the ferment, but since it’s a white wine, fermenting in my 60F cellar, the ferment hopefully will be slow.

The duration of the starter makes a huge difference. For a short term starter (< 2 hours) a small amount of sugar is fine. When doing overnight or 24 hours, a fair amount more sugar is required, so the yeast doesn't run out of sugar. It's best to keep the yeast growing as much as possible.

Just for giggles I figured it out -- 8 oz / 237 ml is about 1% of a 23 liter batch, so I'm not worried if adding 100 or 237 ml water.

Extrapolating your figures to 237 ml water, to reach 13 brix we'd need 2-3/8 Tbsp sugar, so going with 5 Tbsp in 237 ml should push the brix over 26.

So ... you've got me thinking. I don't expect to start another batch until October, when I'll be using multiple strains for each batch. I intend to experiment with numerous amounts of sugar at that time.

 

[Ohio Bob]

Just for giggles I figured it out -- 8 oz / 237 ml is about 1% of a 23 liter batch, so I'm not worried if adding 100 or 237 ml water.

Extrapolating your figures to 237 ml water, to reach 13 brix we'd need 2-3/8 Tbsp sugar, so going with 5 Tbsp in 237 ml should push the brix over 26.

1 cup versus 100 ml is a fair question, for me it’s about staying within my 250ml Erlenmyer flask, allowing for some foaming. I’m quoting my numbers so that someone with a calculator can put it all in perspective. That someone appears to be you!

I would think that the starter should have sufficient sugar content to get the colony building going. But also we do not want to introduce factors that shorten the yeasts life, like yeast death due to high alcohol, or osmotic stress from high sugar levels. From that perspective would you still recommend going with a starter Brix above what might be in your juice?

 

[Raptor99]

I would think that the starter should have sufficient sugar content to get the colony building going. But also we do not want to introduce factors that shorten the yeasts life, like yeast death due to high alcohol, or osmotic stress from high sugar levels. From that perspective would you still recommend going with a starter Brix above what might be in your juice?

I think it makes sense for the starter to have a Brix similar to the must. That way the yeast will get used to the must environment.

But you also need sufficient nutrients. If you do an overnight starter with just sugar and water, the yeast might run out of nutrients and produce H2S.

 

[winemaker81]

I would think that the starter should have sufficient sugar content to get the colony building going. But also we do not want to introduce factors that shorten the yeasts life, like yeast death due to high alcohol, or osmotic stress from high sugar levels. From that perspective would you still recommend going with a starter Brix above what might be in your juice?

Stop making sense! You're confusing me!


I'm thinking out loud here ... using a 240 ml size (rounding up) 12-14 hour starter as the model, if we use too little sugar, it will be consumed before morning. Go with too much sugar, and osmotic stress could be a problem. In 12+ hours, I don't expect high ABV will be a realistic problem, but if we put a cap on the brix, it won't matter.

If my calculations are correct, 2-3/8 Tbsp sugar provides 13 brix, +/-1 allowing for less than careful measuring. This eliminates osmotic stress as a problem, so it comes down to "can the growing colony eat that much sugar in 12+ hours?". Let's not focus too much on the brix -- we're considering a tiny sample (in relation to 23 liters) with a large amount of yeast (5 g) which is designed to inoculate up to 23 liters of must.

My take on this?

Calculations are not going to help nor is conventional wisdom. We need a practical experiment that starts with the above and measures the SG after 12-14 hours. If we have more than 10% sugar remaining, then 13 brix is fine. If we have more, it's still ok. If we have less, then we need to consider adding more sugar to the starter.

The fun part is figuring out how to measure SG in a 240 ml sample using normal home winemaker equipment. The only thing that comes to mind is a refractometer and using the translation table to determine the actual brix.

But you also need sufficient nutrients. If you do an overnight starter with just sugar and water, the yeast might run out of nutrients and produce H2S.

I add 1/2 tsp Fermax to my starters, so that's not a problem for me. However, it is something everyone should consider.

 

[Ohio Bob]

But you also need sufficient nutrients. If you do an overnight starter with just sugar and water, the yeast might run out of nutrients and produce H2S.

Agreed, and I do add 1 TBS of GoFerm. In the context of my previous reply, the conversation was about the sugar content of the yeast starter. Additionally, measuring the sugar concentration after adding GoFerm is likely to skew the results if using a refractometer.

 

[Ohio Bob]

The fun part is figuring out how to measure SG in a 240 ml sample using normal home winemaker equipment. The only thing that comes to mind is a refractometer and using the translation table to determine the actual brix.

You could make a quart of sugar solution to get the SG using your hydrometer, then measure out a smaller amount in which to add nutrients and yeast. You would be sacrificing some sugar, or add more sugar and make it your simple syrup.

 

[winemaker81]

You could make a quart of sugar solution to get the SG using your hydrometer, then measure out a smaller amount in which to add nutrients and yeast. You would be sacrificing some sugar, or add more sugar and make it your simple syrup.

I wasn't clear -- I mean that we make a starter (100 to 240 ml), let it run over night, then how do we check the SG/Brix in so small a sample?

If we use a larger starter, we need to use correspondingly more yeast.