Pretty sure Kosher Coke is made from sugar beet and Mexican Coke is sugar cane. Did they do a run of it this year? If so the store manager should be able to order it for you.

Here's another question - why does Coke need to be Kosher for Passover only?

Certain Jewish groups have rules about not eating corn products during Passover. Coke is regularly made with high fructose corn syrup, so for certain Jewish groups regular Coke is against the rules. The best part for the non-Jewish person is enjoying Coke made with sugar rather than corn syrup. There are glass Coke bottles that are from Mexico but those are $1 a piece for 12 oz. bottles. The 2L of Kosher Coke is much cheaper.

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