Coke and Milk Experiment: What Happens When the Two Drinks Mix?

Coke and milk are two very different drinks as one is a soft drink made with carbon while the other typically comes from a cow or other mammals. As such, there's an experiment that involves mixing milk and coke together for a surprising result.

Coke and Milk Experiment

The coke and milk experiment is a fun simple project that almost anyone can do as long as they have access to the two drinks. The process is very straightforward in that the two are mixed in a see-through bottle for everyone to see the results.

Although the experiment can take a while to accomplish, its results are interesting to watch as the Coke particles can be seen precipitating down until the bottom of the bottle is left with dark particles. Interestingly enough, the top part of the bottle would also be left with strange, clear liquid.

This is what happens in the experiment, as Maricv 84, explains in relation to a video of the experiment that they uploaded to YouTube. As such, what people are seeing in the experiment is actually Coke's phosphoric acid reaction to two tablespoons of milk.

This causes precipitation; and chemically, this is its result: 3Ca + 2H3PO4 -> Ca3(PO4)2 + 3H2. When the phosphoric acid molecules and milk contact each other, they become increasingly dense and start separating.

The phosphoric acid starts to sink to the bottom while the remaining milk and coke mixture rises up. Maricv 84 highlights that although both items are acidic, Coca-Cola has higher acid contents with a pH level of 2.5 to 4.5 with milk having a close to neutral acid level at 6.7 pH.

There are certain studies that suggest that due to phosphoric acid content, which is very high in soft drinks, people who drink too much of it are prone to develop Osteoporosis if they don't have enough Calcium. Coca-Cola is also a great household cleaner as its chemical reaction is good for cleaning things from pennies to degreasing car engines.

History of Milk and Coke

While it is considered as an interesting scientific experiment, this drink has actually been present in different cultures. The concept is an actual drink that South Africans call the "brown cow" and was drunk by Laverne on Laverne and Shirley.

It's also popular in India, given the name the Doodh soda; and in Birmingham, UK, this mix is simply known as "milk coke." This recipe often consists of two-thirds Coke with a third of UHT milk, with the recipe being passed down among Brummies.

Although the recipe might seem bizarre to some, it actually isn't that far from Coke float, which instead of milk involves vanilla ice cream. After all, vanilla ice cream is often made from milk, cream, sugar, and vanilla flavoring.

This would mean the Coke and milk recipe could just be a different version of the Coke float, except with a more liquid mixture.

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