Coca-Cola bottles have yellow caps again — here’s why people are stocking up

They’re back.

If you spotted a slew of Coca-Cola bottles with yellow caps instead of their usual red caps sitting on shelves while on a recent grocery store run, you weren’t seeing things.

It’s the time of year when the popular soda’s packaging gets a pop of color for the Jewish holiday, Passover, which takes place this year from Wednesday evening, April 1, through the following Thursday, April 9.

Those observing Passover traditionally refrain from eating foods that are made from barley, rye, wheat, oats or spelt. Eastern European Jews of Ashkenazi descent, which is most of the Jewish population, take things a step further by also avoiding legumes and corn.

Because of this, every Passover, Coca-Cola, which is technically Kosher year-round but not Passover-friendly, makes batches of its soda with cane sugar instead of high fructose corn syrup, one of its main ingredients, and puts a yellow cap to signify to those observing the holiday that the soda is safe to drink.

This change in the soda brand’s formula dates back to 1935, when Atlanta rabbi, Rabbi Tuvia Geffen, urged Coca-Cola to release a version of their soda that could be consumed during Passover so no one would have to miss out on their favorite drink, according to The New York Times.

Although these yellow-capped bottles are released every spring, technically, Coke fans can consume this high fructose corn syrup-free soda year-round, otherwise known as Mexican Coke, which is sweetened with cane sugar — but the caveat is that it’s usually sold in small glass bottles and is way more expensive.