Too much K Meta added

[cronessa]

Hi All

A colleague at work gave me 3 buckets of shiraz grapes from his family's vineyard which is located in the Riverland here in South Australia about 3 weeks ago. The timing was a bit unexpected and I only had time to do some minimal research so I had to wing it as I went along - in doing so I have made several mistakes, the biggest being that I added far too much Potassium Metabisulfite to the must.

My colleague suggested that I try to make the wine as his father does by using natural yeast fermentation. I crushed the grapes and got a yield of 23 litres (just over 6 gallons) including the skins. I left it alone for about 4 days and took a hydrometer reading which had hardly moved. As it did not seem to be fermenting I decided to add Potassium Metabisulfite (as I noticed some mould on some of the grapes as I was crushing them) and then a commercial red wine yeast.

I sprinkled 3 teaspoons of K Meta directly on top of the 'grape skin cap' and then punched it down into the must. I went back to read the instructions I had been following and immediately noticed my error. I measured the weight of a teaspoon and it was about 4 grams.

I removed the skins straining them through cheesecloth and ended up with 18 litres (4.75 gallons) of juice. I then activated the yeast and added it. There were no signs of fermentation for the next two days (which is obviously to be expected). Following some previous threads on this forum I decided to splash rack the must like crazy to liberate the sulfite. In the two days after I added the yeast I splash racked probably four times each day (twice morning and night). On the third day the fermentation exploded and I got a hydrometer reading of under 1.000 about 4-5 days later which is obviously way too fast.

I then transferred to a demijohn with an airlock where it's sat for about two weeks. I added about 5 litres of a commercial Shiraz Cabernet cleanskin from another local region to fill the demijohn.

The wine actually tastes ok considering it obviously needs ageing (I've had very small sips) but there is a noticeable SO2 smell (I'm guessing this is from the extremely fast fermentation and higher levels of K Meta). I'd say that the SO2 smell is definitely noticeable but I wouldn't say it was overpowering.

So I guess my questions are:

1. Should I try and remove the smell by further racking and perhaps gently stirring the must using copper tubing? There's no way I'm adding Copper Sulphate after my K Meta error!

2. Is the wine going to be safe to drink? I have started research as to whether I can acquire a Sulfite test kit but so far it doesn't appear that they are easy to come by here in Australia (at least for the amateur home winemaker).

Any comments or queries would be greatly appreciated, I've already learnt so much from this forum.

 

[JohnT]

First,

Welcome to the forum...

When you say that you currently have an S02 smell, do you mean that your wine smells like rotten eggs (or does it smell like k-meta)?

In either case, I would advise a splash racking or two. See if that improves your wine before going to the next level of treatment.

 

[GreginND]

John's advice is spot on. And his first question is critical. Too much SO2 and H2S problems are very different. The latter, H2S (rotten egg smell) is the only one you should treat with copper. And I do not recommend stirring with copper rods as you simply can't control the amount of copper you put in.

Try aeration first. It can help both issues and is safest.


Sent from my iPad using Wine Making

 

[Turock]

I also see no evidence of nutrient additions. This can also cause H2S---if it is, indeed, H2S and not just an SO2 smell.

 

[cronessa]

Thank you for your advice and welcome - its greatly appreciated.

It is definitely a H2S smell and I didn't add nutrients to the must during fermentation.

I will try splash racking as recommended. I was a bit hesitant to splash rack at this stage due to the increased risk of oxidation but I guess I have more than enough K Meta in the batch to counter that!

 

[cronessa]

I splash racked from demijohn to a fermenter and back twice tonight and the smell has improved dramatically. It is still faint but I'll check again in a couple of days and rack again if it is still present. At least its smelling more like wine than rotten eggs now and not the other way around!

Hopefully the smell was stronger because it was pooling in the top of the demijohn.

 

[JohnT]

That's great cronessa! Glad it helped.

Definitely give it a couple of days and see.

If the smell persists, I would not advise another splash racking. Instead, you will need to treat your wine with copper. Let us know how it is in a couple of days.

If the H2S is still there, we can advise further.

 

[cronessa]

I opened it up this evening and, whilst there is still a faint H2S smell, it is a lot less noticeable than it was.

I'm hoping it will completely go away in the ageing / bottling process?

Thanks again for all your help!

 

[Turock]

I would treat it with Reduless at this time. You can't ignore a H2S problem because mercaptans will form which are very difficult to treat. www.morewine.com carries Reduless----treat your wine with it an you will resolve the H2S issue. Follow the directions on the package.

 

[cronessa]

Thanks for the advice. I have made enquiries to try and find a stockist for Reduless here in South Australia (there seems to be at least one). Just hoping that they will supply the small amount I require.

 

[grapeman]

Because the Reduless is hard to find there, I would use a piece of copper wire to stir with. Take a piece of wire cable (two or three wire) and cut the plastic jacket off it. Use the shiniest piece to gently stir the wine with for a minute or so. Smell your wine and see if the smell has gone away. You can leave it in the wine overnight if a couple stirs don't get rid of it, but be sure to close the demijohn off to keep the air out. While you can't precisely control the copper exchange using this method, it won't impart too much in that amount of time. It is more to provide a reaction to bind up the H2S.

 

[cronessa]

I found a stockist for Reduless here but they only sold 1Kg lots for AU$80 (US$74).

I stirred the wine with a sterilised piece of copper piping this morning and the smell seems to have gone (I'll check it again tomorrow to make sure).

Thanks again for all your help!