Margi, as far as your kosher questions, sorry folks totally of topic here, let me try to answer in order of your questions.
1. Traditionally kosher wine had to be made by Jews to be kosher, nothing specifically non-kosher about grape and grape product, except the fact that there could have been small bugs on the vine and bugs are big no-no. Thus in Jewish production the special attention was given to that fact.
2. Milk of a kosher animal, cow, goat, lamb, is inherently kosher. However in the olden day in the Eastern European countries when an old woman or a young one for that matter, would milk the cow, and I have seen this with my own eyes even nowadays during my summers spent out in the country side, they would put some pork lard on their hands, a hand lotion of a sort if you will, to make hands softer so not to hurt the udder. And then during milking the milk will sort of drip (unintentionally probably or not) thru the lard laden hands rendering that milk not kosher because it just got mixed in with pork fat, very none kosher item.
In the hot climate there was a different sort of a problem. To keep the cow or goat milk for a long time the owners would mixed it with the milk of a donkey, for some reason milk of a donkey last much-much longer by compressing. Again a kosher item mixed in with not kosher making unfit for consumption. BTW word “kosher” means “fit”, i.e. fit for consumption according to the Torah laws. So to avoid the above problem for milk and furthermore other dairy by products, it is necessary for Jewish supervision. A side note, nowadays in America the rules are so strict that some Rabbis say that it is not a problem to consume regular milk that was produced without Jewish supervision, because the government requirements are so strict that we can rely on those requirements.
A separate issue is with cheese production. The animal rennet used in traditional production. This means mixing of meat and dairy products together which is also not allowed by laws of kashrut.
3. What do you mean by natural foods? Eggs of a kosher bird are kosher and do not require supervision, however one has to know for sure that it is chicken egg you are eating and not an eagle. Honey is consider kosher, as long as there are no leftovers of the bee in it, apparently a lot of times bees lose their legs in honey, that honey would not be kosher. All vegetables and fruits are naturally kosher if not served with bugs that are often found on them, especially on leafy things like lettuce for example. Even water could be a problem. There was some kind of tiny-tiny bugs in the water in some district of New York and the kosher consumer had to buy bottled water. Laws of kashrut are very complicated. Those are just few small examples that do not even begin to scratch the surface of the real issue at large.
If you need/want to know more details, please PM me I do not want to take any more time and space of the topic here and people’s patients (sp?). Thank you and sorry everybody.