Forgot to add potassium metabisulfit

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kimberlygator

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Good morning. I have a question about how to avoid making wine bombs :/ I picked my grapes 2 days ago. Brix at 14. Specific gravity at 1.044. 35 lbs of usable grapes. I have made wine from juice kits before but never from grapes. Frankly, you could have knocked me over with a feather when I saw how many grapes I actually had. So I picked them, washed them, mashed them. I added the yeast and 3 lbs 6 oz. of sugar dissolved in 1/2 gal of distilled water, placed it in primary fermenter with air lock. I then realized I forgot to add the potassium metabisulfite to stop the wild yeast from fermenting. Now I am worried about off flavors, and worse, wine bottles that could explode :/ ugghh. Any thoughts or advice on how to proceed would be greatly appreciated!

Kim
 
SO2 is added upfront to kill any bacteria on the grapes and native yeast. The yeast you added will quickly dominate any wild yeast. If you have an airlock, you are safe from anything exploding, unless it gets clogged. If you ferment the wine dry, shouldn’t have bottles exploding. Nothing to do at this point but watch the fermentation.

Assuming the grapes were wine grapes, I doubt they achieved ripeness at 14 brix. I target 21 for whites/rose and 26 brix for reds. I would also look at adding goferm/fermk to your fermentation protocol to help assure strong fermentation and less chance of H2S.
 
First of all, nothing to worry about with regard to "exploding bottles." That is only a concern if you bottle too early, and we won't let you do that! :)

Did you take a SG reading after you added the water and sugar? (I am guessing, based on some estimates thrown into Fermcalc, that you will be at about 1.070 to 1.075.)

Don't worry about not adding k-meta first. Your wine yeast wil take over.
 
SO2 is added upfront to kill any bacteria on the grapes and native yeast. The yeast you added will quickly dominate any wild yeast. If you have an airlock, you are safe from anything exploding, unless it gets clogged. If you ferment the wine dry, shouldn’t have bottles exploding. Nothing to do at this point but watch the fermentation.

Assuming the grapes were wine grapes, I doubt they achieved ripeness at 14 brix. I target 21 for whites/rose and 26 brix for reds. I would also look at adding goferm/fermk to your fermentation protocol to help assure strong fermentation and less chance of H2S.
I know the brix reading is low - in Texas we are lucky to get much higher than that from what I understand. But this is still new to me - growing and using grapes for wine making. Thanks for the feedback. I have heard that it could be a problem after bottling the wine. As of now it's an experiment :)
 
First of all, nothing to worry about with regard to "exploding bottles." That is only a concern if you bottle too early, and we won't let you do that! :)

Did you take a SG reading after you added the water and sugar? (I am guessing, based on some estimates thrown into Fermcalc, that you will be at about 1.070 to 1.075.)

Don't worry about not adding k-meta first. Your wine yeast wil take over.
Oh, no - I took the SG before adding it. I can take a new reading today - I only added the yeast and sugar last night around 11pm.
Kim
 
@sour_grapes is right -- bottle bombs are not an issue until after bottling.

For future reference, if the wine is bottled with residual sugar but isn't stabilized*, you can get a renewed fermentation in the bottle, which produces more alcohol and CO2. If the bottle is corked, the CO2 may blow the corks and make a mess. If the wine is capped (screw caps, crown caps, etc), the pressure buildup can exceed the bottles tolerance, and can explode.

If the SG is 0.998 or lower at bottling, fermentation is almost certainly done and there is no danger.

* If you backsweeten, add potassium sorbate and K-meta, which prevent a renewed fermentation in a wine that is not actively fermenting. [This is the short version to set your mind at ease. As you get closer to bottling, ask more questions and we will fill in the blanks.]
 
[QUOTE="mikewatkins727, post: 800794, member: 30357"
I would suggest you daily take and record an S.G. reading. This will give you a lot of info on your wine making (how long and how fast it is taking). Also, learn the art of patience.
[/QUOTE]
Great idea! I am trying to track and record as much info as possible. I meant to take the PH before I started and forgot to do that to - I need to make myself a spreadsheet with notes so I don't forget things and have an outline of when to do each thing.
 
I took a SP reading yesterday. It was 15 - that was after adding almost 4 lbs of sugar. Does that sound right? Also, the airlock is not doing anything - should I add another packet of yeast?

Thanks for all the feedback! Kim
 
Kim, Step back a minute, wine made from grapes is a historical beverage, great grandpa coming from Europe did not have metabisulphite or air locks or cultured yeast packets and it worked.

you started Saturday, I would hope to see activity but it might be slow. The most recent batch took four days from inoculation to active bubbles (top is open). For mine, a rhubarb, the pH is 3.13 which is a stress on the yeast. If I thought I would have an issue I could have made a starter with sugar in water and then added a pint of the new juice to train the yeast to live in acid, wait for some growth/ an hour ,, followed a second pint and waiting ,, then adding the starter to the juice.
Adding extra packets will not hurt the fermentation, when nutrients become limited they will stop reproducing.
A starting gravity of 1.044 is low, I usually wait till I see some predation and then pick. If the pH tests lower than 3.0 it will be worth adding some calcium carbonate to increase the pH, ,,, as your fruit ripens acid is metabolized/ removed from the fruit.

Good luck and welcome to WMT
 
@kimberlygator, most things in winemaking take time and very little of it is on human schedule. Yeast does the real work and it doesn't pay any attention to what the humans want. A few pointers:

Specify the scale when posting readings to avoid confusion. I assume that "15" in your last post is brix, but it's best to be clear, as all we have to go by is what you post.

In general, brix is a good scale for pre-fermentation measurement of sugar. Once fermentation starts, alcohol skews the reading so it's not longer accurately indicating the amount of sugar. On WMT we generally use Specific Gravity as it does not include the pre-conceived notion of the amount of sugar. SG is the relative density with respect to water, and as we gain more knowledge as winemakers, we understand that it's not a simple number. The first and last SG readings are fairly clear -- in between it's more of a barometer that indicates how far along fermentation is. Also, use 3 digits to the right of the decimal, to be clear, e.g., 1.040. Folks will post 1.04 and it's unclear if it's 1.040 or 1.004 ('cuz people make typos).

Fermentation "normally" takes off within 48 hours, but there are no guarantees. Sugar, acid, pH, and temperature all affect the fermentation. Depending on the variety, 35 lbs of grapes will probably net 2 gallons of finished wine, so a typical packet of wine yeast is more than sufficient, as it's geared to inoculate 5 to 6 gallons of juice or 70 to 110 lbs of grapes.

During the initial stages of fermentation, yeast needs O2 to reproduce. Fermenting in a sealed container inhibits this. Most of us ferment in food grade buckets with a towel over the top to keep "stuff" out. You'll see a activity as the cap (pulp) rises and forms a solid layer. Stir the wine at least once a day to keep the cap moist and avoid mold from growing.

Keep stirring the wine and post your updates!
 
Bryan, thank you. Yes 15 was brix - thought I wrote that but no doubt was just going to fast and not being clear. It's happened to me before - once or twice ha ha :) I did add another packet of yeast. I might not have needed it but it's in there now so I'll see what happens. I do have an airlock on the lid but the lid it not tightly on the bucket. It's funny - I thought the primary fermenter was supposed to be air tight to keep out wild yeasts and things in the air. It was loose so I wrapped plastic around it. I'll be removing that shortly :) My husband is always saying I have too many plants in the backyard. After I picked all the grapes and he saw how much it's yielding he was asking so could we put grape vines here or over there? I think we will be planting a couple more vines. It's very exciting. I can't wait to see how it turns out. It's the first time doing it with fresh grapes so I am setting a low bar but can't wait to do this again next year when I'll be much better prepared and educated.
 
I did add another packet of yeast. I might not have needed it but it's in there now so I'll see what happens.
More yeast won't hurt -- better too much than too little.

One reason to use commercial wine yeast is that most strains are SO2 tolerant (wild yeasts and bacteria are not), and will crowd out and/or inhibit the wild beasties. Once the commercial yeast multiplies, the likelihood of a wild yeast taking over is very slight. The towel keeps out large things while allowing air flow.

Stir the must daily, completely submerging the cap (grape pulp) -- some folks do it morning and night. When the cap rises into a firm layer, you know fermentation is in progress. The smell is also a strong indicator.

It's easy for experienced winemakers to forget just how complicated this seems at first. My son made his first solo wine last year, and even after a decade plus of being my helper, he made a few minor mistakes. Nothing bad (wine turned out fine), but it was a reminder to me that there is a lot to know to make good wine.

MoreWine! has free manuals available that are worth reviewing.
 
I am pressing the cap down twice a day. I started the primary fermentation last Friday night. We are going out of town tomorrow until Sunday night. I am hoping it will be okay til then. We will move it to the carboy on Sunday.

Kim
 

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