It should have kosher-certification.
As with most products, grape products require kosher certification. If they do not have proper certification, they should not be considered Kosher.
Anything that has a kosher certification on it.
It's a kosher certification agency.
It can be, check the package for kosher certification.
It needs to be cooked in a kosher vessel and have kosher ingredients. If purchased, it (or the bakery) should have kosher-certification.
Capers can be kosher, they require a valid kashrut hechsher (symbol of kosher certification).
The answer is that it really depends on if the product has a kosher certification, or not.
It can be. You'd have to check the packaging for kosher certification.
There are kosher brands of l-taurine supplements. You would have to check the packaging for kosher certification.
Kraft's Catalina dressing is not certified kosher. While some ingredients may be acceptable in a kosher diet, the absence of a reliable kosher certification means it cannot be considered kosher. If you require a kosher product, it's best to look for dressings specifically labeled with a kosher certification symbol.
In the Netherlands, Maltesers are not certified kosher. While the ingredients may not contain non-kosher items, certification is necessary for a product to be considered kosher. It's always best to check for a reliable kosher certification symbol on the packaging. If you need kosher chocolate, look for brands that are specifically labeled as kosher.