On Passover, Jews avoid leavened foods or foods containing leavening ingredients.The yellow caps mean the soda is kosher for Passover.
While browsing the supermarket's beverage aisle, you may have noticed some soda bottles sporting yellow caps instead of their usual colours.
The switch from sucrose (cane or beet sugar) to high-fructose corn syrup made Coca-Cola sodas off-limits on Passover.
The caps also bear the Orthodox Union's Passover kosher certification symbol "O-U-P."
Not only observant Jews appreciate non-corn syrup Coke. Fans of the original sweetener, sucrose, wait all year to buy batches of Coca-Cola with sucrose, claiming it tastes better.