A couple of years ago I started using left over wine for making vinegar. I
have had good results until a few months ago. One of the jars developed a
gelatinous layer on the top of the vinegar. I thought that must be the
"mother". It didn't smell good, but I thought it was only the mother that I
was smelling and the vinegar would still be fine. I've added wine and
additional mothers have formed in different layers. In other words, the
mothers have stratified within the vinegar with vinegar between the lower
layers.

Besides smelling offensive, the vinegar isn't good. I'm throwing it out,
but I would like to know what happened. Some of the information I have read
on making vinegar describes the mother as what I have. When the vinegars
were good, there was no evidence of this jelly like cap on the top of the
vinegar.

Apparently a bacteria started growing that wasn't desirable, but it formed
the characteristic mother. I had the vinegar stored in a cupboard in the
kitchen. I had cheesecloth over the top of the jar. I am wondering if the
temperature may have been too high and the undesirable bacteria liked it
better than the aceto-bacter aceti. The temperature is kept around 70
degrees F.

Any ideas on what went wrong and how I can prevent it from happening again?

Fred