First time making wine, need help knowing if my grapes are ready for harvest!

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aleks88

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Hello! So I've had a few vines growing over a canopy in my yard for over 8 years now. Finally decided to do something with them. They are a wine variety white grape, but I do not remember what type exactly...I've been going back and forth with a local brewing supply store for most of my information, apart from books and online reading thus far. So I pulled some grapes from my vines yesterday, tasted them to find them quite sweet, perfect ripeness Imo, and brown seeds. I then took a hydrometer reading as requested by my local brewing supply store. My brix was at 13.5, so I know I do not have enough sugar. My question is how much chaptalization is too much? I was told I needed around 20-22 brix to get my fermentation process started. I've some some calculations myself, and seem to find that I would need way too much sugar to make this work, what do you all think? Also I plan on using either Lavins K1v116 or EC1118 if that makes any difference. The big issue with me is that they told me I need to wait longer until the brix goes up, but I cannot wait any longer, as the birds are beginning to take my grapes, as well as mold and other issues, and I'd like to have at least 5lbs available to ferment, and I am not sure I will have that much too much longer. Is this a lost cause? Or should I pick what I have and proceed with the chaptalization?
 
Brix alone is not enough. You also need to know your acidity. Easiest way is to buy a cheap pH meter and test some juice. If your Brix is just at 13.5, then your acidity will almost certainly also be not ideal, and can cause problems during fermentation unless corrected as well.

But otherwise, I have brought some fruit from a Brix well under 10 to 22 by adding sugar. It takes a lot of sugar. But it is not a problem doing this.
 
Brix alone is not enough. You also need to know your acidity. Easiest way is to buy a cheap pH meter and test some juice. If your Brix is just at 13.5, then your acidity will almost certainly also be not ideal, and can cause problems during fermentation unless corrected as well.

But otherwise, I have brought some fruit from a Brix well under 10 to 22 by adding sugar. It takes a lot of sugar. But it is not a problem doing this.

Ok. Ill go out and get a meter today. How much sugar so you think I'd need? I came up with a rediculous number. What should my ph read in your opinion?
 
Don’t know what grapes or where you are so it is difficult, but going out on a limb, as it is August, I’d try to let them hang until your pH is 3.1 or more, and they taste ripe. You can go as low as 2.9 but that means a lot of acid.

Ripe is hard to describe but sample a few, some obviously more green and hard and some softer and more golden. If you can tell the unripe, green flavors, are they still there in the riper ones? You can pick riper ones and let the less ripe ones hang hoping they’ll ripen before the birds, mold and whatever get them. Just keep the ones you pick in the fridge. Not ideal, but winemaking is often a balancing act of compromise.

However, if it is pick green, or nothing, I’d say go ahead, add sugar and at least you get to learn for next year. Wine may not be great, but we all do this to learn.

And, as @salcoco says, get your bird netting for next year!
 
One formula is Brix * pH^2 (squared) . Difficult on the iPad without superscript but brix * pH * pH. For whites you aim for 200-220 range. Not perfect but gets you in the ballpark.

As mentioned, acid will be a bigger issue for you than sugar. There are winemaking calculators online that will tell get how much sugar to add given starting Brix, volume, and desired brix or ABV. But if the acid is too high this will be a bigger challenge requiring pre- and/or post-ferment acid adjustments, cold stabilization, etc.

Also, not to be a buzzkill, but know that you will be lucky to get two bottles from 5# of grapes.
 
Thanks for tall the great information from everyone. I went out and purchased a ph meter, the only one i found locally seemed to be for soil, but I was told it works for liquids as well. When I measured a small sample of my must it was ph 2.0...not sure if the meter isnt great or if thats true? I might go out and get a digital one at the brewing supply store tomorrow.
 
Brown seeds is an indicator of ripeness, but wine grapes would typically have > 20 brix when mature. Are you sure you don’t have table grapes? Adding a bunch of sugar will only add alcohol, but I suspect it would overpower any flavor that you have.

I too would suggest invest in some netting. You can make bad wine from good grapes, but you cannot make good wine from bad grapes. I’d look for some additional grapes as well and suggest making a 5 gallon carboy’s worth. That will get you 2 cases of wine, vs 2 bottles you will net from your 5 pounds.
 
I went out and purchased a ph meter, the only one i found locally seemed to be for soil, but I was told it works for liquids as well. When I measured a small sample of my must it was ph 2.0...not sure if the meter isnt great or if thats true?

Your pH is probably below 3 based on your sugar levels, but 2.0 is crazy low. Keep in mind that a meter intended for soil may be geared for measuring in the 4 to 9 pH range. Wine pH may be outside of its wheelhouse.

For this year, you could probably get by with some wine litmus test strips like these. They measure in the 2.8 to 4.4 range. They are ok for white wine. I can't read them if I try to test red wine. Eventually, you will probably want to upgrade to something like the Milwaukee MW102 pH meter.

H
 
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Great resource... I knew the sampling fruit part was involved but this will be a n effort!
 
Thanks for all the great advice! I just got a Dr. Meter ph meter from Amazon. Calibrated it eight away and testes some grapes. Came up to be on 3.4. Im afraid to take more samples to test brix as it takes quite a bit and i don't have much left. But I kind of have to now again do i not? Since i need to know how much sugar to add....last brix reading was 13.5 on the 12th..could it have changed that much in a few days?
 
Thanks for all the great advice! I just got a Dr. Meter ph meter from Amazon. Calibrated it eight away and testes some grapes. Came up to be on 3.4.

Look at the seeds of some grapes. If they are mostly brown, I would pick. White wines should be picked at a lower pH than red wines, and 3.4 is pretty high for a white. Adjust the brix with sugar (yes, it will be a lot).
 
Since i need to know how much sugar to add....last brix reading was 13.5 on the 12th..could it have changed that much in a few days?

The general rule of thumb is that sugar levels can change 1 to 1.5 brix per week. How you sample the berries can cause a lot of variability in the reading. I try not to put too much faith in any one sugar test. I wait to harvest until I see a couple of samples that indicate it is time. After harvest, switch to a hydrometer and measure the sugar from a sample of must juice. Use that reading for chaptalization. Sanitize the hydrometer and container so you can put the juice back into the must.

As baltonwine mentioned, your pH is high for a white. Adding sugar is going to move it a bit higher. Take additional readings after crush and again after sweetening. You may need to add some tartaric acid to bring it down a bit.

H
 
so I found an online calculator that help me figure out how much sugar I need to add, it came out to be about 2 lb 130z to get from 14 brix to 20. I will measure my brakes again after I harvest just to make sure but I wanted to ask how do you guys recommend me adding the sugar? since it is a lot of sugar I wanted to see if I should add it to some water and put that water into my must, or should I add it to some must directly? If I add it to the must should I pull enough must and warm it up enough to melt the sugar and then add it back into the rest of the must? Does the most or water I use to dissolve the sugar and need to be heated or will it dissolve without heating it? If I do heat it how much? also for sugar do you guys just recommend regular granulated sugar?
 
so I found an online calculator that help me figure out how much sugar I need to add, it came out to be about 2 lb 130z to get from 14 brix to 20. I will measure my brakes again after I harvest just to make sure but I wanted to ask how do you guys recommend me adding the sugar? since it is a lot of sugar I wanted to see if I should add it to some water and put that water into my must, or should I add it to some must directly? If I add it to the must should I pull enough must and warm it up enough to melt the sugar and then add it back into the rest of the must? Does the most or water I use to dissolve the sugar and need to be heated or will it dissolve without heating it? If I do heat it how much? also for sugar do you guys just recommend regular granulated sugar?

Regular old granulated sugar stirred right into the must. No sense diluting your flavor, body, etc. with water.
 
how do you guys recommend me adding the sugar?

More advice

  • Add 1/2 to 2/3's what the calculator says at first, let it sit for an hour, then re-measure brix/gravity with a sanitized hydrometer
  • Run the calculator again on that result and your new volume of wine. If you are still at least a pound of sugar away, repeat with another half jump. Otherwise, add the calculator says. Might want to fudge a bit based on how the first addition went
I usually chaptalize by adding plain white sugar like JohnD recommends. Dissolving in water helps it assimilate quicker, but at your pH, you don't want to dilute the juice. Some people might tell you the sugar should be dissolved in water and boiled to kill microorganisms. That is the generally accepted practice for adding sugar to beer and for backsweetening a finished wine, but I think most winemakers feel it is unecessary for the chaptalization of juice

H
 
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Went to the local shop again to get some tartaric acid. They told me not to add it unless my ph was too high. I told them it was 3.4 and they said they're ready. Then i told them my brix is at 14 and they said well then ypu need to wait until it is at least 18. Then may be add sugar. Seemed they were against adding sugar at all.
The general rule of thumb is that sugar levels can change 1 to 1.5 brix per week. How you sample the berries can cause a lot of variability in the reading. I try not to put too much faith in any one sugar test. I wait to harvest until I see a couple of samples that indicate it is time. After harvest, switch to a hydrometer and measure the sugar from a sample of must juice. Use that reading for chaptalization. Sanitize the hydrometer and container so you can put the juice back into the must.

As baltonwine mentioned, your pH is high for a white. Adding sugar is going to move it a bit higher. Take additional readings after crush and again after sweetening. You may need to add some tartaric acid to bring it down a bit.

H
 
Went to the local shop again to get some tartaric acid. They told me not to add it unless my ph was too high. I told them it was 3.4 and they said they're ready. Then i told them my brix is at 14 and they said well then ypu need to wait until it is at least 18. Then may be add sugar. Seemed they were against adding sugar at all.

There is no hurry to add the acid as long as your pH is in a safe range such that spoilage is not likely. 3.4 should be safe, but make sure to measure it at the end of fermentation. You can acidify at that point if you want to get your pH down into the normal range for white wine. Note that both fermentation and skin contact time have the potential to shift the pH up.

As for their harvest advice, keep in mind that there are very few universal truths in grape growing. They say not to harvest until it gets above 18. I have two varieties where most growers recommend harvesting before the brix gets to 18. If I were in your shoes, I would harvest now. I would much rather deal with low sugar than a pH that is getting a little too high for comfort. Knowing the variety would certainly help though.

H
 

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