Chemical taste to wine

[Phoenix]

So I am on my third box wine kit.
The first - a very cheap Sauvignon Blanc can't out wonderful, I like it better than what I can buy in the shops. The second a zinfandel rose is ok. To me it has a bit of a yeasty smell but it tastes ok. The third a pinot blush smells ok but has a chemical aftertaste. Again it's perfectly clear but this one isn't fizzy at all.

All have definitely finished fermenting according to the hydrometer.

Q1. Will the yeast smell go away with aging. The wine is perfectly clear if a little fizzy but reads 998
Q2. The Pinot only came with one finings and no flavour add back. I'm not sure I stirred it as vigorously as the first one either and it took 48 hours to clear after stirring all the others were clear within 24 the rest had two finings in the kit would this possibly cause the chemical taste if the other liquid (I can never remember what it's called but it went in after the first finings and before the second finings in the other two packs? I think there's a pleasant wine if I can get rid of the chemical taste.

I have used the same everything kit wise for all the wines, sterilised everything exactly the same way.

Thank you for any input

 

[cmason1957]

There are at least two possibilities I can think of right away. There are probably 55 really, but these generally are good starts.

1) Not letting the wine take some time to develop. As in not aging it long enough. What kind of timelines are you following. Kit instructions generally are 4-8 weeks and you bottle. I always suggest that you then wait a month and try one bottle taking notes of what you smell and taste, repeat at one month, repeat until no or minor differences are noted. For lower end kits, this might be as little as three months, but could go to a year.

2) Cleaning and sanitization. I know for me this was a hard one to learn. Cleaning - removing any visible or tactile grim. I use oxyclean free or a dedicated cleaner like Powdered Brewery Wash plus elbow grease, cleaning as soon as using an implement. Sanitation - removes most of the microbial gunk you can't see. I use potassium metabisulphite spray (2 tsp kmeta + 1 tsp acid, usually citric) spray liberally, wait a few minutes for the fumes to do what the do, pour any residue, use. Star San is an acid based sanitizer many use.

3) the water you are using to mix up the wine kit. If I were on well water, I would use that, I'm on city water so I go to the store and purchase spring water.

 

[winemaker81]

All of Craig's points are spot on.

You can't do anything about points #2 and #3 for your existing wines, but can for future ones.

#1? Kit timelines work for folks in a hurry, but to make better wine, the wine needs more time. Make the kit to the point of racking off the lees following clarification. Then bulk age 3 months. You'll find the wine at that point is FAR better than it was when it went into the carboy.

 

[Ohio Bob]

This chemical taste which people mention a lot doesn’t always come from a kit. I’ve tasted it in a gallon jug of wine that didn’t fit in the 6g carboy. It may not be the same because but it’s a very distinctive flavor. Not a bacterial spoilage but definitely gets your attention, it’s that dramatic. At least it was for me. I hit mine with a double/triple dose of Kmeta and it eventually calmed down. I ended up using it at bottling, but the tag on the jug said “this might be junk” for months until I decided it was ok. It’s the only time it ever happened this dramatically.

 

[Phoenix]

Thank you all very much lots to think about. The kits I have bought are all "7 day" wines but my house is cold and I've fermented them for about 4 - 6 weeks in the plastic tubs before syphoning into the plastic carboys.
None of them taste "off"
I have bottled as all of them read ok on hydrometer according to instructions after this time.
I'm amazed I can have so many different results.
I am looking to learn.
I'm going to leave them in bottles for another month and try again.
I'm also leaving me the red I started in April because there's something going on after I add the chemicals.
Or to do with the bottles (I have connected)
Maybe washing and sterilizing used bottles means there's possibly something I've not got rid of??

 

[Rice_Guy]

Maybe washing and sterilizing used bottles means there's possibly something I've not got rid of??

Chemical taste is hard to diagnose. The whole wine is chemicals. ,,, it smells like —? it reminds me of —? — > (a lot of taste is smell). ex:
soap?
sewer?
matches?
bandaid?
a wet dog?
salad dressing?
plastic?
the nice fruit is missing?

The issue could be the manufacturer or your water or the corks got moldy or even residue in bottles. The art of wine making is to be able to taste and then name the chemical. (Many ladies are better than men)

 

[Phoenix]

Chemical taste is hard to diagnose. The whole wine is chemicals. ,,, it smells like —? it reminds me of —? — > (a lot of taste is smell). ex:
soap?
sewer?
matches?
bandaid?
a wet dog?
salad dressing?
plastic?
the nice fruit is missing?

The issue could be the manufacturer or your water or the corks got moldy or even residue in bottles. The art of wine making is to be able to taste and then name the chemical. (Many ladies are better than men)

It doesn't smell. It tastes of polyurethane with a dash of petrol

 

[Phoenix]

It doesn't smell. It tastes of polyurethane with a dash of petrol

The other batch (different wine) smells of yeast but tastes ok

 

[Phoenix]

It doesn't smell. It tastes of polyurethane with a dash of petrol

I mean it smells like wine.. there's no hunt of the after taste in the smell..

 

[Rice_Guy]

It doesn't smell. It tastes of polyurethane with a dash of petrol

Fusil oil: produced as a byproduct of yeast stress as from low nitrogen or high temperature in the fermenter

 

[Phoenix]

Fusil oil: produced as a byproduct of yeast stress as from low nitrogen or high temperature in the fermenter

Oh that doesn't sound good. I'm guessing the whole batch is wasted?
Would that happen from leaving it too long in the fermenter?
My house is cold so it can't be from heat and I'm guessing the nitrogen is in the packets?

 

[winemaker81]

Oh that doesn't sound good. I'm guessing the whole batch is wasted?
Would that happen from leaving it too long in the fermenter?
My house is cold so it can't be from heat and I'm guessing the nitrogen is in the packets?

Nitrogen is yeast food. Adding yeast nutrient to a must helps keep the yeast happy.

How cold is your house, and how much does the temperature vary between day & night?

I ferment my fall wines in my cellar, which is typically between 63 and 67 F, and have no problems. I've had wines finish in as little as 4 days.

 

[Rice_Guy]

A kit should provide appropriate nitrogen to feed the yeast, it might have been off. , low oxygen in the growth phase. ,, What else could produce stress?
Petrol taste urethane? >> also could be new equipment with machine oils or some soaps, variations in city water

The customer decides if the flavor is a defect and tosses the food or if it is an annoyance

 

[Phoenix]

Nitrogen is yeast food. Adding yeast nutrient to a must helps keep the yeast happy.

How cold is your house, and how much does the temperature vary between day & night?

I ferment my fall wines in my cellar, which is typically between 63 and 67 F, and have no problems. I've had wines finish in as little as 4 days.

My house rarely gets above 53.6 F
I have been wrapping the fermenting tubs in duvets near a radiator but the radiator is only on for about an hour 3 x a day and I rotate the tubs when it's on.

 

[winemaker81]

My house rarely gets above 53.6 F

There are yeast stains that thrive below 60 F, but it's still not ideal. I suggest you get a heat belt. Others on the forum use them and someone may be able to suggest products to you.

 

[Rice_Guy]

12C is not optimum growth temp but yeast are hearty buggers. 12 will not kill them, where as 35C will kill yeast plus cause stress related chemistry.
I have run yeast at 10C (cellar conditions) for a three week ferment and at 5C for an eight week ferment.

 

[BPL]

It doesn't smell. It tastes of polyurethane with a dash of petrol

Lots of guessing depending on the methods and manufacturer of the kits. The "dash of petrol" may come from fusel's produced by stressed yeast, pointing to the methods used and the length of time the wine is in contact with lees after fermenting. All fusels are not bad. Some are used in the shaping of the wine. The urethane taste is another matter. This points to the kit and materials used either in the kit or additives during fermenting. Yes, nitrogen is needed for healthy yeast, but how it's added and the type makes the difference between apparently "happy" yeast and "healthy" yeast. Yeast given raw Nitrogen (DAP) will definitely be "happy", but similar to 5 year old children given energy drinks for breakfast. Excess Nitrogen (from DAP) + internal heat of the must can lead to unwanted fusels. Usually, this is a hotly debated subject. I mention excess Nitrogen because some common "yeast nutrient" uses a blend of Urea and DAP which is a power house of raw Nitrogen. It can easily be added in excess, usually added blindly without consideration to other factors. (This blend of "yeast nutrient" is cheap and one of the reasons it's still used IMO.) While DAP can be used, the excess Urea combined with the Ethanol in the wine forms Ethyl Carbamate or Urethane. The Ethyl Carbamate production from excess Urea is one of wine making's dirty little secrets (IMHO) and not spoken much about. So, what you are experiencing may be a combination of factors. Yes, I've been down the road of funny tastes in wine over the years. I removed the common "yeast nutrients" AKA raw nitrogen, focused on adding my own nutrients (namely Fermaid products) and control fermentation temperatures. The funny tastes went away. Good luck with your future wines.

 

[Phoenix]

Lots of guessing depending on the methods and manufacturer of the kits. The "dash of petrol" may come from fusel's produced by stressed yeast, pointing to the methods used and the length of time the wine is in contact with lees after fermenting. All fusels are not bad. Some are used in the shaping of the wine. The urethane taste is another matter. This points to the kit and materials used either in the kit or additives during fermenting. Yes, nitrogen is needed for healthy yeast, but how it's added and the type makes the difference between apparently "happy" yeast and "healthy" yeast. Yeast given raw Nitrogen (DAP) will definitely be "happy", but similar to 5 year old children given energy drinks for breakfast. Excess Nitrogen (from DAP) + internal heat of the must can lead to unwanted fusels. Usually, this is a hotly debated subject. I mention excess Nitrogen because some common "yeast nutrient" uses a blend of Urea and DAP which is a power house of raw Nitrogen. It can easily be added in excess, usually added blindly without consideration to other factors. (This blend of "yeast nutrient" is cheap and one of the reasons it's still used IMO.) While DAP can be used, the excess Urea combined with the Ethanol in the wine forms Ethyl Carbamate or Urethane. The Ethyl Carbamate production from excess Urea is one of wine making's dirty little secrets (IMHO) and not spoken much about. So, what you are experiencing may be a combination of factors. Yes, I've been down the road of funny tastes in wine over the years. I removed the common "yeast nutrients" AKA raw nitrogen, focused on adding my own nutrients (namely Fermaid products) and control fermentation temperatures. The funny tastes went away. Good luck with your future wines.

Thank you that makes good sense.
I'm going to look for alternative yeast nutrients if I get this type of kit again.
And yes the fermenting tubs were new, so although I thought I washed and sterilised them all the same perhaps I didn't and I will take more care. Although now the tubs aren't new any more so if it was that I shouldn't have the same problem. thank you for your knowledge.

 

[Phoenix]

12C is not optimum growth temp but yeast are hearty buggers. 12 will not kill them, where as 35C will kill yeast plus cause stress related chemistry.
I have run yeast at 10C (cellar conditions) for a three week ferment and at 5C for an eight week ferment.

It seemed to be bubbling away quite well but it did take about 3 weeks to stop. I was worried about lifting the lid to test gravity but is it ok to do this and if so how often?
I'm going to set off a couple of other kits whilst we are having slightly warmer temperatures my hose is now at a balmy 15 degrees

 

[Rice_Guy]

* Opening it up, for the first third of sugar consumption the yeast are creating new cells which requires oxygen. On whites and fruit wines I will use an open bucket till the gravity gets to 1.060 or 1.050. (Many will cover the bucket with a towel which is oxygen transparent)
* If I a using a PET big mouth bubbler or glass wide mouth I will just float a hydrometer in the wine.
* When I am doing a low temperature test I will run the overnight just inoculated at room temp (18 to 24C) to grow out the yeast population and then move the bucket into a temperature controlled fridge. Yeast are competing with assorted bacteria for the sugars and I want them to have a head start. An option you might consider is to warm some water with Fermax (starter nutrient) or juice to 30C and hold this in an insulated drink cooler so it stays warm/ close to yeast maximum.
* fermentation is exothermic, if you wrap your bucket with towels it will be a few degrees above ambient. Some folks will intentionally cool a fermentation bucket in an ice chest with ice. You can also do the opposite as put a hot tea kettle in the ice chest and cover everything with a blanket.

Wine is fairly forgiving while it is out gassing. There are lots of ways to get to the same end point. ,,, > What do the yeast need? Optimum?