This is the "quick and dirty" version, forgive any stupid spelling or grammar errors.
If you have apples, blackberries, plums (or any fruit) to use, grab them and smash them anyway you can, with berries and plums I just used my hands, apples get shredded in the food processor. I remove the pits from the plums, apples you can seed or leave the seeds in. Put them in a sterile, large glass jar or crock (no plastic or metal), with a wide mouth and belly. Hopefully your fruits are sweet and juicy if not you can add some water and sugar (about 1/4 cup of sugar to 1 quart of water).
Apples shredded processed in food processor
Put a cloth over the jar, cotton or several layers of cheese cloth is good, you want air to get in and to keep the fruit flies and other things out. Secure the cloth with a rubber band or elastic.
I don't recommend using chunks but some say it works fine
This is Blackberry and mixed fruit vinegars, I keep them in their own cabinet
***If you're adding water use de- or un-chlorinated water. If the water has chlorine, heat it and let it sit over night so that the chlorine dissipates.
***White table sugar is best and it will all be gone in the end, but you can use other sweeteners too, honey, molasses, raw sugar or succanet etc. I don't think stevia would work, it's not for flavor but to turn the juice to alcohol. You can fill the jar almost to the top with the fruit mash if you have enough fruit but leave a few inches of head space. In a few days the mixture will start to bubble and the fruit will look gross and puffed, floating on top.
This is plum pulp after 4 days
The fruit will float on top until it is finished with the first ferment
Give it a sniff and/or a taste (if you're brave), every day while stirring so you know whats going on in the fermentation process, and keep stirring down the mash every day to prevent any mold from taking over and to introduce oxygen.
Stirring introduces oxygen and releases CO2 This helps prevent mold from colonizing
After a few more days you should start to smell alcohol, that's what you want to happen. Eventually, depending on your surrounding temperature (warmer is better), the mix will stop bubbling and the fruit will sink to the bottom.
Plum fruit settling to the bottom
When this happens it's time to strain out the fruit. Don't worry if the thick sediment gets through just strain out the solids and squeeze the juice out, I use a muslin bag to strain, you can use several layers of cheese cloth with a strainer or a good sieve.
Strain out the solids
Put the juice back into the jar
Put the juice back in the jar, cover again with the cloth secured with a rubber band, and put it back in a warm dark place. You should still stir and sniff it everyday. If everything goes right in a few days to a week, you'll start to see a film on the top, it might look like a silky white powdery layer, kind of wrinkly and bubbly, it might look like an oil slick floating on the surface, or a few white jelly fish looking globs floating near the surface. As long as you don't see any fuzzy black specs or fuzzy white specs, or smell mold you're fine. If you see them fish them out and/or strain again and make sure you stir it often until you see one of the films described earlier.
When the film starts to form:
Stop stirring everyday and let it grow.
Always check for molds, black, green or white and fuzzy. Make sure it either smells like fruit, alcohol (wine) or vinegar. A slight yeasty smell is okay too.
1) when you see the silky type film first (it may also be bubbly), it's kam yeast and it's going to turn into the "mother" which makes the vinegar. Browning or dark discoloration, in the bubbles in lighter colored liquid is also normal as long as there is no fur. You might smell yeast also instead of alcohol. It's going to be an ugly lumpy, bubbly looking process and you might think it's ruined, just let it go and it will start to congeal, and thicken into a funky looking, under cooked, english muffin that covers the entire surface of the liquid.
Yeast on the surface before the mother forms
Yeast and sugars turning to cellulose Symbiotic Colony of Bacteria and Yeast aka Scoby, mother, vinegar plant...
Fully grown mother protecting the liquid below and doing her magic, transforming sugar and yeast to acetic acid
2) The transformation is not as ugly when you get an "oil slick" looking film *lol* The film just thickens and looks sort of like solidified fat or oil sitting on top of liquid and covering the surface.
This mother of apple cider vinegar was disturbed before it covered the surface but you can see it looks like oil or wax floating on top
Mother of Plum vinegar just beginning to form 4 days after straining out the pulp
Mother of a Beer vinegar experiment, silky smooth and white
Blackberry vinegar mother, they take on the color of the liquid
Sitting on top conformed to the shape of the opening and nice and thick (blackberry)
3) From floating globs, the floaters will stay near the surface and begin expanding until they cover the surface All three types are fine, they just begin in different stages of the ferment.
Floating mother blob, usually happens when the mother is very young and gets disturbed (stirring or bumping) she will try to stay as close to the surface as she can to make a new mother
Now the mother will be eating the rest of the yeast and sugar in the alcohol and changing them to acid. You can move the jar around to check on it, but try not to bump it if you can help it. Don't poke at the mother, you want it to keep floating and it sinks if you jostle it too much. It's not a disaster if it sinks, another one will grow back right away but my theory is, while it's growing you might be losing some of the strength of the acidity.
The mother has fallen and a new one has taken it's place
So leave the mother sitting and try to take a sniff daily to see what's happening, eventually you'll start to smell vinegar just faintly, then one day you'll take a whiff and feel your nose hairs burn and know you've got vinegar!
At this point I get a clean drinking straw, put my finger over the top of the straw,and very gently slide it between the mother and the jar down into the liquid to trap a bit in the straw for tasting.
Do the happy dance if it makes you pucker!
When you taste it you'll probably disturb the mother, it might sink or part of it might go under the liquid, it will grow back and replenish it's cover though in a few days. If the mother grows back quickly it means it is still working hard so let it keep sitting, keep sniffing etc. Usually I know it's done when it smells and tastes good and sour and the mother sinks straight to the bottom from the slightest disturbance. That's when I strain it again, bottle it (in glass) and cap it. I put mine into big wine bottles. A mother will always grow back as long as it's still in the open container, and sometimes it will grow another one after straining and bottling...not a problem, it won't be as thick, just a film or jelly like floaters, it's good to have it in the vinegar. The vinegar can be stored in a cool dark place and you can let it age,or you can start using it when it's finished.. Some makers age them for years, I don't know the benefits of aging yet because I haven't had enough time, patience or experience. I'll let you know because I have a lot of batches finished and finishing and I know I can't use them all at once, so I'll find out.
Good luck and I'll answer any questions I can.