Apple blossom wine

I have a ornamental apple tree in my back yard and know that dandelion and rose petals can be used for wine so I wonder if I followed the danelion wine recipe is there any reason I cant substitue the apple blossoms instead?

This is the tree and a close up of the blossom

Absolutely go for it. I have an apple blossom mead planned once it blooms (spring is really taking it's time this year).
I figured that 2 quarts of lightly packed blossoms per gallon of must would be about right (based on other floral wines), and use a slower fermenting yeast (that won't blow the delicate flavours out of the airlock)--I'm planning D-47 (if it's cool enough), or Cote des blanc.

I was going to use kv1-1116 since it is good at retaing flavor in fruit wines and has a low nutritional requirement

are apple blossoms GRAS?

You may want to taste them and compare to something like dandelion blossoms to see if you need to adjust the amount of them. I find that dandelion flowers don't have all that much taste to them so the 4 quarts of picked flowers (with the green base still attached) is about right. After i pluck the petals off the volume reduces to around 3 quarts.

So if the apple blossoms have a lot more flavor maybe start with 3/4 or 1/2 the amount? I am not sure how you might need to pluck the petals off or just toss the whole flower in?

This gives me an idea - we have an ornamental Chinese apricot tree that flowers in January when not much other fruit/flowers are going so might need to give that a whirl.

Apple blossoms, as do the seeds and leaves, contain hydrocyanic acid (cyanide) ... however, people are known to use those blossoms (and others with the same chemical such as cherry blossoms etc) for making tea, steeped into vodka, and eaten.
Personally, I would not use those blossoms for wine.
Dandelions and roses are very different than stone and seeded fruit (which also contains the chemical).

If you decide to do it anyway, I'd do a lot of research first.
Often the "agricultural extension" departments of major universities (such as Michigan State University, etc) have data like that. You might check with an educational institution.