Why does sugar free soda fizz way more than regular soda?


Why does sugar free soda fizz way more than regular soda?

In: Chemistry

Artificial sweeteners in diet sodas are much sweeter than regular sugar so you need to add less of it to get the same sweetness. Diet sodas are usually >99% carbonated water with < 0.2 grams of artificial sweetener.

In contrast, regular sodas have a great deal of added sugar. A regular 12 oz (355 mL) can holds about 10 teaspoons or ~40 grams of sugar. This is about 10 sugar packets per can! Because there is so much sugar, the volume of carbonated water is lower in regular sodas so it can’t hold as much fizz.

The carbonation levels are the same. Sugar-free and sugar-based drinks have different foaming properties. You’ll notice that the bubbles in the foam on sugar-free drinks are bigger.

Different sweeteners mask the bitterness from the carbonated water (which is acidic) differently. This bitterness is important in the perceiving fizz. Sugar based drinks are also slightly more sticky (viscosity).

So, it is really the perception of fizz (mouth-feel) that is different and that’s in part due to the bubble size, stickiness, and taste.