The Herb Guild I am a part of makes herb and fruit vinegars to sell at the Botanic Gardens here. For fruit vinegars, we simply wash and dry well (my understanding is that any extra water will dilute the vinegar and lower the acidity that keeps bacteria from forming). We then place in a gallon jar with whatever herbs we like and cover with vinegar (white wine in our case, but cider should pair well for this application). In my experience, I see no reason why the pulp/skins wouldn't work, though you may end up with more of a tannin flavor from the grape skins, rather than the sweetness, since you've already pulled a lot of the sugars out with your juice. Personally, I would do the smaller batches, so that if one doesn't work, you can just dump it without losing all of it, and fill the jars about 1/3 full of pulp to start, or try a few different amounts. Also, it would be a shame to waste the vinegar if you find you don't use the end product. If you like it, expand production next year? I don't know for sure, but I would be concerned with the vinegar eating the seals on the spigot on your larger dispenser jar.

I would taste your vinegar every few days to decide when it gets to the point you want it. I've had herb vinegars get bitter steeping in two weeks, while others steep longer with no problem. You could also consider some spices such as some anise stars or cinnamon sticks. Fennel seed may pair very well too. Ground spices generally tend to cloud vinegars and don't work that well. I would wait until you strain the pulp from the vinegar to deal with sugar, heating the vinegar to below boiling and stirring briskly to dissolve. Add just enough to sweeten to your taste and uses. Personally, I store my vins filtered, with no remaining herbs or fruit.

You may have already discovered this fact sheet in googling and old searches, but it's still good info.

Here is a link that might be useful: Fact sheet on making flavored Vinegars

On re-reading my question, I can see that it sounds like I just want a fruit flavored vinegar, but I want to actually make it...not just flavor existing vinegar. I have Bragg's organic apple cider vinegar with the mother in it that I was just going to use as a starter, not the whole thing. Maybe it would be better if I used the grape juice itself, instead of the fruit pulp and scraps, and added the mother to it to make vinegar? I sure don't want to add sugar to it later. I thought that was part of the vinegar making process early on.

Hmmm...nobody else responded. What recipe did you decide on? It does sound like a fun project, and I would love to hear the outcome (knowing that will take months).

I ended up not doing the project this time. Processing another batch of grapes this weekend so there's another opportunity to try this, if I decide on it.

All I know how to make "wine vinegar" is to make it from wine. I have made wine, beer and wine vinegar too.

First: There are yeasts(various strains) that convert sugar into alcohol, similar to waht is used in baking bread. The sugar can come from fruit juice or you just dissolve sugar in water, then add the yeast ... (follow process)

Second: Once you have wine, add mother vinegar to it and stir it once in a while to get oxygen into it. The the mother vinegar( which is a kind of bacterium ) will take the alcohol and oxygen and convert it into "acetic acid". So the amount of acetic acid in wine vinegar is directly related to the amount of alcohol contents of the wine, from which wine vinegar is made. (and the amount of alcohol in the wine is directly related to the amount of sugar in the grape juice).
So what is called "vinegar" is a diluted acetic acid to around 4 to 5%

If you leave an open bottle of wine open, There is a chance that it might become vinegar. (It often turns into acetone.) But the bacteria have to get in there , somehow.
The word "VINEGAR" is French meaning Sour Wine. So the first vinegar was made by accident.

Third: in the process of making wine, if the vinegar making bacteria are present , and you stir it(or leave the container open), then as the yeast produce alcohol, the bacteria will digest it and convert into vinegar.

Good wine vinegar, is more expensive than the wine from which it is made, reason being that there is an extra process and man hour is required to make it. So, I dont think that you can make a decent wine vinegar from the grape pulp. More importantly, it will not have enough sweetness, unless you add sugar to it. I would rather buy some economical wine and make vinegar from it.

This post was edited by seysonn on Sat, Sep 7, 13 at 11:30

The leftover grape skins and seeds is called pomace. You can google and find some information of uses for the pomace.
Another idea you might like is to make fruit "shrubs" from some your pomace. I have made several combinations this summer and put into sealed jars until closer to the winter holidays. I will transfer into small bottles for gifting.

Maybe I just need to get some chickens and I can feed it to them!

I understand your question. You want to make 'fruit scrap vinegar'. Using the scraps from processing fresh fruit. I also use Braggs and wanted to make my own vinegar from my harvest. I have 3 different ones going now. Asian Pear, Apple and Concord grape.
(i used the Braggs as a mother)
A good book understanding fermentation is Sandor Ellix Katz, The Art of Fermentation

I'll link a fact sheet from Ohio State

here is another
http://thenourishingcook.com/how-to-make-fruit-scrap-vinegar/

I searched and read through many processes but the basic is one qrt clean filtered water
to 1/4 cup raw sugar or honey and two tbsp vinegar 'with mother'. My containers are large so i just doubled.

This is what got me going and linked to other sites...http://www.leaningshed.com/recipes/grape_vinegar.html

here is my concord vat...day one....It has been about a week and looks as it should.
I may bottle it today or tomorrow. Some let it go longer. I may have used too much fruit but it smells divine. (i have an abundance of fruit this year)

Here is a link that might be useful: making cider vinegar at home

Important to note that it is not recommended to use this method vinegar for home canning.

"Homemade vinegar can only be safely used for pickling if it has at least 4.5% acetic acid. All commercial vinegars are that acidic or more so. You can test your homemade vinegar's acidity by using an acid titration kit, available from home winemaking suppliers."

Here is a link that might be useful: 'about' apple scrap vinegar