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Yes, it will not be "unsafe," whatever that means.

BTW, in your original post, I think you are confusing acid content and pH. I believe they are recommending you not change your TA (titratable acidity) by more than 0.3% (AKA 3 g/liter). I don't think they are talking about moving the pH by a certain amount.
 
Well that introduces a whole new dynamic I'm unaware of then.....

My equipment includes
a) a hydrometer to measure SG
b) a refractometer to measure SG/Brix scale
c) a pH tester to test what I've understood to be acid content.

The SG/Brix part is easy for me to understand.

The acid part is a bit tricky for me. I understand a higher acid content needs dilution and a lower acid content needs enhancement to get to a given point.

The reason I say "understood" above for the acid is I don't know the differences if there are any. Last year I used one of the eye-droppper/sample and drops in solution to look for a color change to black that was extremely difficult for my tired eyes to see those changes. So my beer/wine making friend said get a pH test meter so I did. A little reading and what has been presented here, I've been targeting on the pH meter 3.2 to 3.6. I've assumed that in the ballpark of .65% taratic acid content by the way I did it last year.

Could you please explain in newbie terms what I don't know and if I've again screwed this up or again need to do something to salvage this?

Last years batch was drinkable but a bit tart and all I did was wash/cull/de-stem and crush, put the juice in a primary, add spring water to get the eyedropper test at what I thought was .65% tartaric based the number of drops I added, kept adding sugar until the SG was 1.100 and pitched yeast. Let that rock for about a week then siphoned off to clean secondaries, and then a third or fourth rack before bottling.

My 1st primary is:
5 gallons / SG1.095 / Brix 24.8 / 3.6pH

My 2nd primary is:
5 gallons / working on the SG&Brix now / 3.1pH

My 3rd primary is:
5 gallons / working on the SG&Brix now / 3.1 pH
 
So what I'm hearing is there are three components for basic wine and not two.

Last year I was testing for .65% tartaric acid with a kit, and then SG start to finish with my hydrometer. Two things.

This year I've been testing for what I thought were the same things, but it appears there's tartaric acid, pH and SG (Brix with my refractometer) making it three things in the mix. Is that correct?

Edit To Add:
Well a little poking around and I found this article which what I believe explains the differences.
Source: How to measure acidity TA in wine

Looks like there's no easy way to measure TA other than the drops either with the test kit or in conjunction with the pH meter? And I read you need to recalibrate the pH meter EVERY time you use it? My kit only came with one test packet for the low 4.01 range. Argh..... This is a ballistic learning curve/baptism by fire for sure.
 
Last edited:
So what I'm hearing is there are three components for basic wine and not two.

Last year I was testing for .65% tartaric acid with a kit, and then SG start to finish with my hydrometer. Two things.

This year I've been testing for what I thought were the same things, but it appears there's tartaric acid, pH and SG (Brix with my refractometer) making it three things in the mix. Is that correct?

Edit To Add:
Well a little poking around and I found this article which what I believe explains the differences.
Source: How to measure acidity TA in wine

Looks like there's no easy way to measure TA other than the drops either with the test kit or in conjunction with the pH meter? And I read you need to recalibrate the pH meter EVERY time you use it? My kit only came with one test packet for the low 4.01 range. Argh..... This is a ballistic learning curve/baptism by fire for sure.

OK, let's reign this back in a bit. pH is a measure of the strength of the acid in a wine, TA (which stands for Total Acidity, not Tartaric Acid) is a measure of the quantity of acid in the wine. pH is measured with a log scale, TA is expressed in grams / liter or a percentage of grams per liter (6 grams/liter is the same as .6%). And yes TA is determined by performing a titration, which is what you were referring to above.

You and I have been working on getting your pH raised in your must to a point where alcoholic fermentation will not be unduly stressed, and subsequently, this raising of pH will also lower the TA, but we've not been focusing on TA, as many don't when adjusting must prefermentation.

Don't get sidetracked right now with TA, focus on getting your pH correct, into the 3.2ish range, getting your SG up to the starting point you want, and doing it without adding water and thinning the body and taste of your wine. If your other two musts are at 3.1, you're almost there with the pH. Adjust as discussed, little bits at a time so you don't overshoot your goal.

When you feel that you've mastered pH adjustments, you can test both pH and TA in your must and work to adjust both of them into a workable range at the same time, they don't change predictably, nor at the same rate. Later, when your wine is done, you can monkey around with TA and taste test with different levels of added sugar to overcome any residual tartness if needed.
 
Whew.....

I packaged up the 48lbs of cleaned grapes into three 2-gallon pails and they're in the freezer for another day when I free up some gear.

And I've been working diligently (i hope) on hitting these target numbers.

My pH meter is by Jellas

My refractor simply says "ATC" on the top. I used it in conjunction with my Hydrometer and they were in check with one another.

The acid tester (Vintners Best/LD Carlson) I used requires a 15cc sample of product where you add three drops of Phenolphthalein Indicator Solution. Then slowly agitating the sample with the drops, start adding Sodium Hydroxide keeping track of how many cc's it takes to make the color change dark and stopping when no additional SodHyd is added. That's a tough thing to do if you don't do colors well let alone shades. But I did each one two or three times so I'm confident the numbers are good.

My targets were:
pH: 3.2ish
BRIX: 24-25
SG: 1.095-1.100
Acid: .65%

Bucket #1
Volume: 5.0 gallons
pH: 3.5
BRIX: 24.8
SG: 1.095
Acid: .65%

Bucket #2
Volume: 5.0 gallons
pH: 3.2
BRIX: 24.8
SG: 1.095
Acid: .63%

Bucket #3
Volume: 4-5/8 gallons
pH: 3.2
BRIX: 24.8
SG: 1.097
Acid: .50%

So I'd say everything is on track except Bucket #3 and it's acid. On my shelf of stuff i have, it includes "Acid Blend - Food Grade Citric Maltic and Tartaric Acid", Yeast Energier, Yeast Nutrient and Wine Tannin.

I'm "guessing" I need to use the Acid Blend to get the acid content up to .65%. But there's zero instructions on how to use it.

So I think there's one more hurdle with the acid of #3 and then it's time to prepare my yeast and pitch it, right?

How do I use the Acid Blend for #3 and is the yeast straight forward by the packet label?
 
Whew.....

I packaged up the 48lbs of cleaned grapes into three 2-gallon pails and they're in the freezer for another day when I free up some gear.

And I've been working diligently (i hope) on hitting these target numbers.

My pH meter is by Jellas

My refractor simply says "ATC" on the top. I used it in conjunction with my Hydrometer and they were in check with one another.

The acid tester (Vintners Best/LD Carlson) I used requires a 15cc sample of product where you add three drops of Phenolphthalein Indicator Solution. Then slowly agitating the sample with the drops, start adding Sodium Hydroxide keeping track of how many cc's it takes to make the color change dark and stopping when no additional SodHyd is added. That's a tough thing to do if you don't do colors well let alone shades. But I did each one two or three times so I'm confident the numbers are good.

My targets were:
pH: 3.2ish
BRIX: 24-25
SG: 1.095-1.100
Acid: .65%

Bucket #1
Volume: 5.0 gallons
pH: 3.5
BRIX: 24.8
SG: 1.095
Acid: .65%

Bucket #2
Volume: 5.0 gallons
pH: 3.2
BRIX: 24.8
SG: 1.095
Acid: .63%

Bucket #3
Volume: 4-5/8 gallons
pH: 3.2
BRIX: 24.8
SG: 1.097
Acid: .50%

So I'd say everything is on track except Bucket #3 and it's acid. On my shelf of stuff i have, it includes "Acid Blend - Food Grade Citric Maltic and Tartaric Acid", Yeast Energier, Yeast Nutrient and Wine Tannin.

I'm "guessing" I need to use the Acid Blend to get the acid content up to .65%. But there's zero instructions on how to use it.

So I think there's one more hurdle with the acid of #3 and then it's time to prepare my yeast and pitch it, right?

How do I use the Acid Blend for #3 and is the yeast straight forward by the packet label?

Leave it like it is, if you try to increase the TA, you’ll drop the pH, don’t want that. Pitch your yeast and get your AF going ASAP.

Since you have no pulp and skins, your nutrient levels are probably low, so plan out your nutrient additions. Take the recommended dosage for each bucket, and add half of it to each bucket when fermentation gets started, and the second half to each bucket when your SG gets down to around 1.060.

Just sprinkle the yeast on top of the must, cover it back up, and let it sit undisturbed until it takes off.

We have a saying here that you’ll hear a lot, “Pictures, or it didn’t happen”
 
Well, the yeast is in. Thanks for getting me this far.

Pictures huh? Nothing fancy, just iPhone snaps

Here's the root for the significant majority of this years pickings... I'm guessing about 10" in diameter which makes me wonder how old it is...
i-3fQBMhm-XL.jpg


The vines can grow 30-40' per year but they don't produce on all that new growth. This one is a literal canopy over a large cedar tree.
i-jmD3KNP-XL.jpg


This is the 117lbs of gross pickings
i-7hXbjJk-XL.jpg


And here is the net 101lbs of culled/cleaned and de-stemmed grapes.
i-Mq2BPHT-XL.jpg


This is the mess that took over my kitchen for the past few days. It's looking a lot more 'normal' now.
i-HrvGFTb-XL.jpg


This is my little dedicated winery. :) The three bottom right buckets are #1/#2/#3 as referenced above.
i-K6n8C4M-XL.jpg


Mixing the EC-1118 up. This was a learning experience. Instructions said between 104 and 109*F. So I got my ThermoPen out and measured 107*F at the faucet. As a test I poured 50cc in the cup and checked the temperature. The house is 74*F as was the glass so it cooled the small volume of water down quickly. Hmmmmm..... Lets bump that faucet to 120 and see what happens. I could grab the water, pour it in the cup and by the time I had opened the packet, the temperature was back in range and stayed put.
i-NGvLF27-XL.jpg


....and a few Hail Mary's tossed in with the yeast for good measure!
i-RLnCwrf-XL.jpg


That's about where we're up to in this story. I'm sure I'll have more questions in the next day or so. The plan is to add nutrient once it gets fermenting going, monitor SG and when it hits .995+/- I'll rack it off to a glass carboy/airlock setup. From there I'll just monitor it and see what happens. And when I have a question, I'll just drop it here!

Again John, thank you for everything so far.....
 
Thanks!

Quick question..... Last year I remember I had my plastic pail primaries under an airlock w/vodka in the airlock. I've seen so many pictures of people doing primary fermentation under a closed bucket. Right now, mine is open to the room via the airlock hole. If I need to cover that, is duct tape adequate on the exterior? Or some other plug? I don't have solid tops but if needed can run into Austin and get some.

What's the proper way to perform primary fermentation? Closed top / Open hole / Airlock? Secondary and on will definitely have an airlock. But how about primary?
 
Thanks!

Quick question..... Last year I remember I had my plastic pail primaries under an airlock w/vodka in the airlock. I've seen so many pictures of people doing primary fermentation under a closed bucket. Right now, mine is open to the room via the airlock hole. If I need to cover that, is duct tape adequate on the exterior? Or some other plug? I don't have solid tops but if needed can run into Austin and get some.

What's the proper way to perform primary fermentation? Closed top / Open hole / Airlock? Secondary and on will definitely have an airlock. But how about primary?

It's an open debate, either will work, and folks here do it both ways. The main goal is to allow CO2 out while preventing anything else in, like bugs, flies, dog hair, dust, dirt, etc., and it does not need to be airtight, as the CO2 being produced protects / blankets the wine from overexposure to oxygen. Since access to the must is sometimes mandatory, like for punching down the cap or stirring, some find it more convenient to have the container covered by a towel, or the lid sitting loosely on top. When the lid is loosely on top, as it sounds like yours is, I normally shove a paper towel partway into the hole to keep anything from falling / scurrying through the hole and into the fermenter.

Personally, my preference is a covered, but not airlocked fermenter, with the only exception being white wines, which I ferment in carboys, at cool temps, and under airlock, to preserve delicate flavors / aromas.
 
Thank you John.
When I run home for lunch I'll put a pc of paper towel in the holes as you referenced. I couldn't bring myself to peek this morning inside those primaries. Nerves?

Oh, and I ran the pH on the pressed grapes as I was preparing more to raise the acid contents. Scale read pH of 2.6. I didn't think to try the acid test and SG/Brix on raw grapes until after I had them in the freezer for several hours. I suppose I can run over to the tree at lunch, grab a few and press them for those. I don't think those metrics will have changed much in four days. Or will they? Now that I think about it, when you test the acid content, it would be the slurry (skins&juice), right? But when you check the SG/Brix of the grape, is it just the 'meat' juice? Or is it also the slurry?

What I like most about this discussion is the process. My only prior experience was last year following a little 20 page paperback 'recipe' book with basic instructions. The more I read of other sources, the more I was confused. Now - and much thanks to you - I have a much broader understanding of how this works. Still in infancy, I'm feeling like I kind of 'get it' now and how you approach this/solve problems. I'm thinking the next big thing are all the additives to modify things/bring things in-line etc. Someone asked me what it's like to make wine. I said "It's a whole lot of up front labor followed by a bunch of chemistry and then waiting to see if it worked". I still hold that thought. I've got the labor part nailed. It's just the chemistry, steps and little details I need to fill in to make a drinkable product. I have zero aspirations of making a lot of wine. Heck, just looking at 15gal in primaries is a lot of wine and if I calculated right about 60+ bottles. That's one a week to drink! I DO want to try some other wines as well.
 
Thank you John.
When I run home for lunch I'll put a pc of paper towel in the holes as you referenced. I couldn't bring myself to peek this morning inside those primaries. Nerves?

Oh, and I ran the pH on the pressed grapes as I was preparing more to raise the acid contents. Scale read pH of 2.6. I didn't think to try the acid test and SG/Brix on raw grapes until after I had them in the freezer for several hours. I suppose I can run over to the tree at lunch, grab a few and press them for those. I don't think those metrics will have changed much in four days. Or will they? Now that I think about it, when you test the acid content, it would be the slurry (skins&juice), right? But when you check the SG/Brix of the grape, is it just the 'meat' juice? Or is it also the slurry?

What I like most about this discussion is the process. My only prior experience was last year following a little 20 page paperback 'recipe' book with basic instructions. The more I read of other sources, the more I was confused. Now - and much thanks to you - I have a much broader understanding of how this works. Still in infancy, I'm feeling like I kind of 'get it' now and how you approach this/solve problems. I'm thinking the next big thing are all the additives to modify things/bring things in-line etc. Someone asked me what it's like to make wine. I said "It's a whole lot of up front labor followed by a bunch of chemistry and then waiting to see if it worked". I still hold that thought. I've got the labor part nailed. It's just the chemistry, steps and little details I need to fill in to make a drinkable product. I have zero aspirations of making a lot of wine. Heck, just looking at 15gal in primaries is a lot of wine and if I calculated right about 60+ bottles. That's one a week to drink! I DO want to try some other wines as well.

Your evaluation of the process is pretty much on track, at least as far as task performance goes, there's lots of "farmer" parts and "artist" parts to learn, and much of that comes from experience. Being able to taste grapes in the field, know where they are, when they'll be ready, and what processes to select for making your wine that year to get the best you can out of the crop. Fortunately, some of this can be measured scientifically, but not all.

The conventional wisdom surrounding testing grapes on the vine involves taking a representative sample of the grapes, normally from different parts of the vineyard (wouldn't apply in your case I suppose), and smashing / macerating the grapes, pulp, skins, etc, and then filtering the resulting juice (through a fine strainer or cheesecloth or the like) to obtain a sample free of large particulates, then do your testing. It only takes a couple of drops to check the BRIX / SG with a refractometer, maybe a couple of ml to check the pH with your meter. You should do something similar when testing / adjusting must prior to AF. I typically mix well and scoop a bit (juice, skins, pulp and all) and put into a blender to puree it, then dump it into cheesecloth to collect the juice to test, works fine for me, doesn't take much.

As far as how the acid and sugar change on the vine, let me first say that I don't know much about muscadine grapes and their development, but assume that they progress on the vine in a fashion similar to the more familiar vinfera grapes. As they hang and mature, the acidity decreases, the sugar content increases, the seeds mature from a green to brown color, the tannins mature, and the flavors mature, all things you can see, measure, and taste. I do not know what your grapes' pH gets to when mature, but you can figure it out by monitoring the BRIX and pH every few days, and recording the readings. Grapes destined for white wine are normally picked early, while they still have some acidity in them (3.2, 3.3 or so). Grapes destined for big red wines are harvested later, letting the BRIX get up into the mid 20's or so, which can put pH's in the upper 3's in warm climates. Things like rainfall and drought can also affect the sugar / acidity, so harvesting at the proper time from a weather standpoint is in play as well. Your grapes may never reach BRIX in the 20's, or pH above 3, I just don't know about muscadines, but maybe one of our other members who grows them will chime in. Might be that you picked too early at 2.6, might never get better........You gotta be a farmer first, bolstered by the wine knowledge you have in your head, and the recorded history about how your particular vines grow, produce and mature, to pick at the right time.
 
Perfect explanations in terms I can understand... Thank you.

Last year when we harvested, the grapes were a bit smaller and the skins had begun to shrivel just a little bit. In my mind I thought we were late but the challenge had been set to "lets try this". This years harvest was about 2 weeks later than last years, and the grapes were much 'fuller', 'plump', and the skins 'tight'. Color of the skins was considerably more consistent across all vines too. (don't you just love my non-technical descriptions?) So we decided it was time to pick. I'm fully aware that these differences are due to everything from how the soil may change year to year, sunshine days, rainfall throughout the year and temperature but don't really understand the correlations. Since they (Muscadines) just grow by themselves without tending to them, I've looked at it like "it is what it is". Now you've got me really thinking about developing a monitoring program to see if I can develop some baseline data from which to work. Like average monthly temperatures and rainfall amounts from now until next year's harvest. And if I can grab some grapes today and do the testing on them, I'll have that baseline data to look for changes as they mature into next year. Don't laugh, but I gave thought to this fall when the temps are cooler to actually cutting back and trying to train these vines on a structure with irrigation of some type. That's where my head goes with things like this...

Again, thank you.
 
Perfect explanations in terms I can understand... Thank you.

Last year when we harvested, the grapes were a bit smaller and the skins had begun to shrivel just a little bit. In my mind I thought we were late but the challenge had been set to "lets try this". This years harvest was about 2 weeks later than last years, and the grapes were much 'fuller', 'plump', and the skins 'tight'. Color of the skins was considerably more consistent across all vines too. (don't you just love my non-technical descriptions?) So we decided it was time to pick. I'm fully aware that these differences are due to everything from how the soil may change year to year, sunshine days, rainfall throughout the year and temperature but don't really understand the correlations. Since they (Muscadines) just grow by themselves without tending to them, I've looked at it like "it is what it is". Now you've got me really thinking about developing a monitoring program to see if I can develop some baseline data from which to work. Like average monthly temperatures and rainfall amounts from now until next year's harvest. And if I can grab some grapes today and do the testing on them, I'll have that baseline data to look for changes as they mature into next year. Don't laugh, but I gave thought to this fall when the temps are cooler to actually cutting back and trying to train these vines on a structure with irrigation of some type. That's where my head goes with things like this...

Again, thank you.

For the most part, you're harvesting wild fruit, maybe the best you can do is monitor the BRIX / pH a couple times a week and try to pick when the acid isn't as low and hard to deal with. In my experience, it's a bit harder to manage high acid / low pH than the inverse. You're doing just fine.......
 
Yeast Pitch +24hrs update.

All three buckets have a foamy yeast layer on top covering about 70% of the surface area. Certainly no big bubbles and boiling action yet. I looked at my log from last year and I didn't even record measurements for the first two or three days so I'm not horribly concerned.

At what point should I add my Yeast Nutrient (Food Grade Urea and Diammonium Phosphate)? In a day or so if it begins to take off or tomorrow?

And with that Yeast Nutrient there were no instructions other than 1tsp/gallon. Is that stirred directly into the must? Mixed with water, dissolved and then added? (i'm guessing not the water method am-i-right-am-i-right-am-i-right?) :) And I'll only use 1/2 of the recommended amount based on your input.

....and then I have Yeast Energizer (Diammonium Phosphate, Springcell, Magnesium Sulfate). Is there a preference between the two?

Thanks in advance!
 
Yeast Pitch +24hrs update.

All three buckets have a foamy yeast layer on top covering about 70% of the surface area. Certainly no big bubbles and boiling action yet. I looked at my log from last year and I didn't even record measurements for the first two or three days so I'm not horribly concerned.

At what point should I add my Yeast Nutrient (Food Grade Urea and Diammonium Phosphate)? In a day or so if it begins to take off or tomorrow?

And with that Yeast Nutrient there were no instructions other than 1tsp/gallon. Is that stirred directly into the must? Mixed with water, dissolved and then added? (i'm guessing not the water method am-i-right-am-i-right-am-i-right?) :) And I'll only use 1/2 of the recommended amount based on your input.

....and then I have Yeast Energizer (Diammonium Phosphate, Springcell, Magnesium Sulfate). Is there a preference between the two?

Thanks in advance!

Energizer is like candy for yeast, I don’t use it. On to nutrients, of course you have DAP, let’s work with it this year, next year we’ll consider using DAP and Fermaid K. FWIW, I just measure the dosage, dump it into the must, stir, and move on. First half dose one you have active fermentation.
 
Yeast Pitch +48hrs update.

All three primaries appear to be starting a foam cap and I can hear a slight bubbling if I get close. There are definite differences between the three in the quantity of that cap, but they all three have one which I take to be a good sign. I also added 2.5tsp of Yeast Nutrient to each primary which is 1/2 of the recommended amount.

Measurements this evening include:
I'll put a "/" between readings to keep them in one place to note change. I'm tracking this on a spreadsheet at the moment. The refractometer is tough to read, even when adjusted to my eyes and that's why I think there's some minor discrepancy in some of these.

Bucket #1
Volume: 5.0 gallons
pH: 3.5 / 3.4
BRIX: 24.8 / 24.0
SG: 1.095 / 1.094
Acid: .65%/Not Measured

Bucket #2
Volume: 5.0 gallons
pH: 3.2 / 3.0
BRIX: 24.8 / 24.7
SG: 1.095 / 1.095
Acid: .63%/Not Measured

Bucket #3
Volume: 4-5/8 gallons
pH: 3.2 / 3.2
BRIX: 24.8 / 24.8
SG: 1.097 / 1.095
Acid: .50%/Not Measured
 
Yeast Pitch +48hrs update.

All three primaries appear to be starting a foam cap and I can hear a slight bubbling if I get close. There are definite differences between the three in the quantity of that cap, but they all three have one which I take to be a good sign. I also added 2.5tsp of Yeast Nutrient to each primary which is 1/2 of the recommended amount.

Measurements this evening include:
I'll put a "/" between readings to keep them in one place to note change. I'm tracking this on a spreadsheet at the moment. The refractometer is tough to read, even when adjusted to my eyes and that's why I think there's some minor discrepancy in some of these.

Bucket #1
Volume: 5.0 gallons
pH: 3.5 / 3.4
BRIX: 24.8 / 24.0
SG: 1.095 / 1.094
Acid: .65%/Not Measured

Bucket #2
Volume: 5.0 gallons
pH: 3.2 / 3.0
BRIX: 24.8 / 24.7
SG: 1.095 / 1.095
Acid: .63%/Not Measured

Bucket #3
Volume: 4-5/8 gallons
pH: 3.2 / 3.2
BRIX: 24.8 / 24.8
SG: 1.097 / 1.095
Acid: .50%/Not Measured

If you’re really using a refractometer, and not a hydrometer, it’s time to switch to the hydro, as alcohol distorts the readings in a refractometer, which then need to be corrected mathematically for a proper SG / BRIX.
 
If you’re really using a refractometer, and not a hydrometer, it’s time to switch to the hydro, as alcohol distorts the readings in a refractometer, which then need to be corrected mathematically for a proper SG / BRIX.

John - Thank you. Just another little bit of important information in the learning process! I'll use my hydrometer from now on once yeast has been pitched. I might not be able to see the finer details of what the Brix numbers are with it, but I can surely see the SG numbers on the scale with the hydrometer. I'm getting ready to take some measurements here shortly and see if any movement happened last night with the addition of yeast nutrient.
 
John - Thank you. Just another little bit of important information in the learning process! I'll use my hydrometer from now on once yeast has been pitched. I might not be able to see the finer details of what the Brix numbers are with it, but I can surely see the SG numbers on the scale with the hydrometer. I'm getting ready to take some measurements here shortly and see if any movement happened last night with the addition of yeast nutrient.

Lots of people do just what you are, working with refractometers before pitching yeast requires only a few drops of juice, and really easy to read through the eyepiece; then switching to the hydrometer to monitor fermentation.
 
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