Biogas and Vinegar

I have access to loads (read nearly unlimited amounts) of waste apple cider vinegar I was doing some research on methane digesters and read conflicting things. I saw it explained that the basic methane process is thats sugars convert to alcohol which converts to acetic acid (vinegar) which converts through methane digestion. I also read that methane digestion only happens, or happens best, near a neutral PH. So which is it?

Could I fill a 275gallon IBC tote with ACV and add chicken manure/plant waste and make methane? Or would I be better off with a slurry of just water and the compost material. I am confused please enlighten me.

I can't answer that, but I'm curious too, will bump your question in hopes of someone wise answering it.
I am curious though, where is all the vinegar coming from? That has all kinds of interesting uses!

I have read a little bit about this in The Biogas Handbook by David House. He writes about a double chamber digester that allows the methane stage to happen separately from the acetic/alcohol stage. The first chamber is filled with material that ferments, once it has fermented it is added to the second chamber that also contains methanogenic bacteria where methane digestion occurs. I admit, i've only skimmed the book, but your post rang a bell when i read it.

Here is a link to the biogas book:
https://www.amazon.com/gp/product/0915238470/ref=as_li_tl?ie=UTF8&tag=theforestgard-20&camp=1789&creative=9325&linkCode=as2&creativeASIN=0915238470&linkId=ea31a8104a8f603c6fcf3bbb1b3b1764

I think I read on the solarcities.eu site that if you overfeed a digester it will go acetic and kill the methanogenic bacteria. The double chamber may keep that from happening. I have started construction on double IBC digester with a 3" pvc pipe linking the 2 totes. It hasn't been charged with anything yet, just filling it with water from the roof catchment. Once its full I'll be adding duckweed and cow manure to it.