sour skittles

Question

Hi, Are sour skittles kosher? Ingredients: Sugar, Corn Syrup, Partially Hydrogenated soybean oil, citric acid, friut juice from concentrate (grape, strawberry, lemon, lime, orange), Less than 1% - Dextrin, natural and artificial flavors, gelatin, food starch-modified, coloring (includes yellow 6 lake, red 40 lake, yellow 5 lake, blue 2 lake, blue 1 lake, yellow 5, Red 40, yellow 6, blue 1), Ascorbic Acid (vitamin C). If they are kosher, why is the natural grape flavoring ok? Is there any issur linking back to yayin nesech?? please kindly explain. thanks for your time and patience.