WineXpert Changing yeast for kit wines, in general

[David219]

It seems as though there have been a lot of threads discussing differences in yeast choices and yeast nutrients. My understanding, in synthesizing everything that I've read in these threads and in other resources, that some yeast have higher nutritional needs than others. Kit wines generally come with yeast that yields consistent fermentation with no need for additional nutrients to be added by the winemaker, but may have had nutrients added to the must already by the manufacturer.

If you want to use a different yeast than supplied with the kit, how do you determine the nutritional demand of the yeast and how much nutrient to add so that the yeast is adequately supplied, but not adding so much that unused nutrient is left in the finished wine?

 

[Julie]

Just out of curiosity, why would you want to change the yeast?

 

[David219]

I want to experiment. So far, the only major things I have altered from the kit instructions have been time (like bulk aging) and temperature control. From what I have read, changing the yeast for a particular varietal might yield better mouthfeel or enhance varietal expression. It seems many people feel that the kit supplied yeast is pretty... "foolproof", but doesn't add anything to the character of the wine. Have you experimented with different yeast strains in kits?

 

[Rocky]

Dave, you are correct that you can improve the wine with specific rather than general yeast parings. The manufacturers of the kits usually include a "bullet proof" yeast to assure successful fermentation, e.g. Lalvin EC-1118. This is not necessarily the best choice for a particular variety but it will get the job done with minimal angst. Here is a link to a great article on the subject. It is rather lengthy but gives a good overview of the subject. http://morebeer.com/public/pdf/wyeastpair.pdf

Good luck and happy winemaking.

 

[David219]

Thanks, Rocky. The article you referenced is one of the chief things I have read that has piqued my interest in experimenting with different yeast strains.

But I've also read some comments that caution against changing yeast. That kits undergo extensive bench testing to match yeast to the nature of the must (which is different that pure juice or grapes because of how it is processed). Changing yeast poses serious risks of developing off tastes and smells, particularly H2S production, that would significantly adversely affect the final product. At least that is my understanding of the counter-argument. Plus you void any kit warranty, for what that's worth...

I guess I'm looking for specific input from people who have tried changing yeast and how they managed yeast nutrients. Some have written extensively on this forum about YAN, with calculations and equations...I'm not sure I want to go down that road quite yet. I'm looking for a "rule of thumb" possibly...sort of like the 1/4tsp addition of K Meta with kits...they don't ask you to test for free SO2, but know (through their testing), that that amount puts you in a nice, safe range of suitability.

I don't want to "over-fertilize". I'd like to add just enough so that there is not a lot of extra, unused nutrient floating around in my final product. Are there any assumptions that can be safely made as far as the available nutrients already present in kit wine must and a safe "rule of thumb" amount of supplemental nutrient that should be added for a given yeast strain? Is that too complicated, given the number of strains out there, or can they be lumped together enough (like low, medium, and high nutrient demand) to make such generalizations possible for kit wines?

Even though kits are extensively tested and are a different animal than pure juice or grapes because of how they are processed, is the competitive environment such that kit manufacturers need to produce the simplest, fastest, most predictable product? Might different yeast strains indeed produce a superior end product, but because it would require either more time or more complex instructions, the manufacturers don't pursue it because it might make the kits less fail safe and possibly less marketable to the masses?

 

[Rocky]

Dave, I re-read that article because it had been some time since I looked at it. It seems to me that they are talking about fresh grapes and not kits or juice. What leads me to this conclusion is that there is a reference to being able to try different approaches at the rate of "one shot each year" implying when grapes are harvested. With kits and juice buckets, this would not be the case.

As far as yeast nutrients are concerned, I rarely use them and only if I have a difficult fermentation. I note that in the article they do recommend Go-Ferm and Fermaid-K additions. I like to keep chemicals to a minimum in my wines but that is just a personal preference. My skeptical side notes that MoreWine! sells all of these yeasts and nutrients.

Further, I am a little skeptical of the "extensive bench testing" done by the manufacturers. I seems strange to me that they go through all of this intricate and exhaustive testing and always come up with the same answer: Lalvin EC-1118! I don't want to influence what you do, but I plan to do the following. I have a WE Eclipse Zinfandel and three WE Selection Pinot Grigio kits to start some time soon. I think I will try one of the recommendations for Zinfandel and perhaps a two or three for the Pinot Grigio and see what results I get. Then, I can either blend or segregate the different Pinot Grigios. This will start to build my own personal data base.

I like to experiment with wines so this is not new to me. I would say further that I have never been very disappointed in any of my experiments. Some were definitely better than others, all were very drinkable and none had to be "buried at sea."

 

[David219]

There are a few reasons behind my desire to experiment, other than just the desire to try something different! First, I have a WineXpert Australian Shiraz kit that is over a year...maybe two...old. The yeast might still be perfectly fine,but I look at it as a good excuse for trying a different yeast.

Second, is the fact that while I think my red wines are good (and I think I have grown to prefer them over inexpensive commercial wines), I don't know that I would rate any of them as outstanding. Even with aging, they just don't have a full bodied mouthfeel to me. Seeing some of these yeast strains "advertised" to give greater mouthfeel makes me want to try one and see.

And as you said, many posts (including this reference)seem to be referring to winemaking with grapes or juice. I am hoping for some replies from people who have had some experience with changing yeast with kits and how they handled nutrients.

 

[chrisjw]

Second, is the fact that while I think my red wines are good (and I think I have grown to prefer them over inexpensive commercial wines), I don't know that I would rate any of them as outstanding. Even with aging, they just don't have a full bodied mouthfeel to me. Seeing some of these yeast strains "advertised" to give greater mouthfeel makes me want to try one and see.

While there are several ways to get better mouthfeel with a kit, the best way IMO is to make a premium full bodied wine kit with grape skins, and then age it for 2 years, and they will be outstanding.

 

[robie]

While there are several ways to get better mouthfeel with a kit, the best way IMO is to make a premium full bodied wine kit with grape skins, and then age it for 2 years, and they will be outstanding.

I agree. The difference in mouth feel brought on by a specific yeast is not going to be significant for a kit. It will make a difference, but only slightly. Buy the premium kits that have a grape pack. Red kit wines are simply going to be thinner than non-kit wines. I you want more than that, you will need to use an oak barrel to concentrate the wine.

I like to experiment with other yeast. Ec1118 has a low to medium nutrient require. If you use a yeast that doesn't go ahead and add nutrient based on nutrient/yeast requirements. There is a little in the juice but if you use a full dose of nutrient, it won't hurt anything.

 

[David219]

Thanks for the reply, Chrisjw. Maybe I'm still missing something, though. I don't know. I tend to gravitate toward higher end red kits... Limited Edition, skins kits, etc. I have a WE Lodi Ranch 11 Cab kit that is coming upon two years in the bottle, bulk aged around three months in a carboy.

I also have some objective feedback from wine competitions. I just had two WE LE kit wines judged at the Indy International Wine Competition (Shiraz/Viogner and Primitivo). They both were awarded medals, which is nice...but a silver and bronze, respectively, which effectively puts them "mid-pack" relative to other entrants. Both had been resting in bottles since the summer of 2011. I was hoping for better showings...

Have you tried changing yeast? You mentioned a number of ways to improve mouthfeel. What are some others you've tried?

 

[Dugger]

I have no experience with changing yeasts myself, but a previous member of this forum, bzac, has done extensive tweaks to kit wines and his recommendation was to not change from the included yeast. His experience was that different yeasts did not improve the wine and in some cases detracted from it. If you do a google search for " zax favorite kit tweaks" you will find a thread (I really need to learn how to do a link) and there is also a sticky of one of his tweak threads under Kit Winemaking on this forum.

Edit - link as mentioned above. http://www.winepress.us/forums/index.php?/topic/22899-zax-favorite-kit-tweaks/page-1
(Easier than I thought!!)

 

[David219]

@robie: my next investment will be a barrel and SO2 testing equipment. So your opinion is that if I use a different yeast, it is ok to use the full nutrient recommendation for whatever strain I choose? Does yeast come with recommended nutritional supplement information?

 

[David219]

@Dugger: I've seen one of his posts regarding this. He made the most compelling argument NOT to change the yeast provided by the kit manufacturer. Some others have speculated that non-used additional nutrient could be utilized by spoilage organisms, so you could have too much of a good thing.

 

[cpfan]

David219:

You mentioned a WE Aus Shiraz as the kit that you might like to try a different yeast with. My first question is...what yeast came with the kit? Replacing EC-1118 is one thing, replacing a different yeast is something else. At least, IMO.

BTW, Winexpert uses a much wider range of yeasts than the other kit manufacturers. Vineco has been using three varieties (primarily EC-1118). RJ Spagnols has used EC-1118 solely for many years, but I just read about one of their kits with a different yeast. Not sure about Cellar Craft. Since WE uses a wider range of yeasts, I would be less inclined to substitute for their selection.

Steve

 

[David219]

Steve: it comes with Red Star premier cuvée, dated best buy 12/14, so it is still well in date. I have only made WE kits, but I have seen some variety in the yeast supplied. I am going to take better notes from now on to better track it. I know I also had a recent kit that had two yeast packets, one of which was rc212.

 

[robie]

@robie: my next investment will be a barrel and SO2 testing equipment. So your opinion is that if I use a different yeast, it is ok to use the full nutrient recommendation for whatever strain I choose? Does yeast come with recommended nutritional supplement information?

Sorry, I had the wife standing over me wanting the computer, when I made that post to you, so let me rethink this.

If the yeast you want to use has a higher nutrient requirement than the yeast that comes with the kit, add the difference when the instructions on the nutrient say. If your yeast has same or less requirement, don't add any extra. A yeast like BM45, as an example, has a very high requirement. If you don't add the difference, you could easily end up with a stuck fermentation.

What you don't want to do is to double the dose of nutrient. If you end up adding a little too much, it's not like the wine is ruined. As you have probably heard before, this is not rocket science.

When you ad the nutrient, it is likely to foam up for several hours to a full day, so add it while the wine is still in the fermenter bucket and don't rack until you are sure it is not going to foam up (create a wine volcano).

Sorry for the mix up on my last post.

Again, nothing wrong with experimenting with different yeasts. Everyone has their own opinion. I would not do so unless you have made a few kits per the instructions.

 

[David219]

Robie: so, the yeast nutrient has recommendations for the different strains? If I understand, then, it can be assumed that the provided yeast requirements are met by the kit, so by checking the nutrient needs of both the provided strain and the strain to which you want to change, add the difference? Is there a chart with various strains provided with yeast nutrients?

 

[chrisjw]

Have you tried changing yeast? You mentioned a number of ways to improve mouthfeel. What are some others you've tried?

I have not tried changing yeast but have done all of the other BZAC tweaks including the use of Biolees and Tan'Cor Grand Cru. I have also tried reducing the water and the addition of glycerin (for a cheap wine kit). The water reduction worked for me but it took 3 years for the wine to shine. I probably will not do it again. My limited experience with Biolees was good. Not sure about the Tan'Cor. Glycerin was too sweet.

I bulk age my kits for 6-8 months for more. I do not add finings to my red wine kits unless I am trying to correct a fault (for example, too much tannin), nor do I filter my red wines. For some wines I add 1-2 French Oak spirals (med plus toast). I try to hold off drinking until two years.

I also suggested that you use full bodied kits. You mentioned a WE Shiraz, and LE kits. I do not know about the kits that you are making but WE does not make full bodied Shiraz (but they do have med-full). I am not impressed with any of the LE kits that I have done. They are OK but I wonder if it just a gimmick for the mfgrs to rid themselves of their leftovers. Try out some big Italian reds (with skins) if you want full bodied (for example, WE Int Sel Brunello, Eclipse Barolo, or an Amarone). I would also recommend the Winery Series Tempranillo Cabernet.

 

[SouthernChemist]

Most of the time I think kit manufacturers advise against changing the yeast because of the potential difficulty in managing temperature, nutrient requirements, etc. the majority of people making kit wines do not intend, I feel, to bulk age their wines for 2 or more years. They do not have barrels, do not wish to change the oak, and possibly will not even be fermenting the kit themselves.

That being said, I'm all in favor of serious experimentation with wine. Feel free to change up the yeast, but keep in mind there will always be limits based on the kit. A mid-line kit will not outshine a ultra premium kit based on the changing of yeast alone...especially for a red wine. The changing of yeast leads to more subtle differences, and it's difficult to know for sure unless you directly compare the kit with the original yeast and another kit with the changed yeast. Don't expect a massive increase in body or mouthfeel just from changing the yeast, for example, but it can be improved.

I don't know that you will find a specific amount I nutrients per strain. Usually they just list the requirement as 'high' or 'low'. I could be wrong. Also, i do not think it is as much an issue with a kit as opposed to making, for example, a mead. The kit already has nutrients added, though we do not how much. My guess is that the manufacturers err on the side of caution and have relatively high levels of nutrients. Either way, you would probably have to add a lot to really affect the final product in a negative fashion.

Keep in mind you also have the ability to add quality tannins, more oak, to barrel age the wine (which will really put you closer to a quality wine in a store if done long enough, and other options.

 

[David219]

@Dugger: thanks for the link. I was able to find an abbreviated version of that thread by searching this forum, but your link is way more comprehensive. I've started reading it, but I think I need to start earlier in the day...my eyes are getting tired tonight!