The Core Sweeteners: Aspartame and Acesulfame Potassium
Pepsi Zero Sugar achieves its sweet, zero-calorie profile through a carefully formulated blend of two high-intensity artificial sweeteners: aspartame and acesulfame potassium (also known as Ace-K). Using a combination of sweeteners is a common industry practice because it offers several advantages over using a single sweetening agent. For instance, a blend can often create a more rounded, natural-tasting sweetness, reduce lingering aftertastes, and enhance the overall flavor perception.
Aspartame: An Amino Acid-Based Sweetener
Aspartame is an artificial sweetener about 200 times sweeter than table sugar. It is made from two amino acids, aspartic acid and phenylalanine. Unlike some other sweeteners, it provides a small amount of calories, but because such a tiny quantity is needed for sweetening, the caloric contribution to the final beverage is negligible. One important consideration is for individuals with a rare genetic disorder called phenylketonuria (PKU), who cannot properly metabolize phenylalanine. For this reason, all products containing aspartame, including Pepsi Zero Sugar, carry a warning label for phenylalanine content. Aspartame is not heat-stable, which is why it is typically not used in baked goods.
Acesulfame Potassium: The Stable Synergist
Acesulfame potassium, or Ace-K, is a synthetic sweetener also approximately 200 times sweeter than table sugar. It is particularly valuable for its heat stability, which allows it to maintain its sweetness even when heated during processing. Ace-K is frequently used in combination with other artificial sweeteners, like aspartame, to produce a more balanced flavor and mask any slight aftertaste. It is not metabolized by the body and therefore provides no calories.
Pepsi Zero Sugar vs. Diet Pepsi
Many people wonder if Pepsi Zero Sugar and Diet Pepsi are the same product with a different name. While both are sugar-free and rely on a blend of aspartame and acesulfame potassium, they are not identical. The formulas contain slightly different proportions of ingredients, which results in a noticeable difference in taste. For example, a 2025 comparison noted that Diet Pepsi had a tangier, spicier profile, while Pepsi Zero Sugar tasted smoother and richer.
| Feature | Pepsi Zero Sugar | Diet Pepsi |
|---|---|---|
| Primary Sweeteners | Aspartame, Acesulfame K | Aspartame, Acesulfame K |
| Flavor Profile | Deeper, bolder, more traditional cola flavor | Lighter, tangier taste |
| Additional Ingredients | Contains Calcium Disodium EDTA (preserves flavor) | May contain Potassium Sorbate (preservative) |
Ingredient Variations and Reformulation
It is important to note that the formula for Pepsi Zero Sugar can differ depending on the market. In North America, the product was once known as Diet Pepsi Max and Pepsi Max before being renamed Pepsi Zero Sugar in 2016. An important reformulation occurred in the US in January 2023, which reduced the caffeine content, removed the ginseng extract, and adjusted the sweetener system. However, the core blend of aspartame and acesulfame potassium remained. In many international markets, the product is still known as Pepsi Max, and while it also uses aspartame and Ace-K, the specific ingredient proportions and formulation are not identical to the North American version. For the most accurate ingredient information, consumers should always check the nutritional label of the product they are purchasing.
What About Sucralose?
Some people may confuse the sweeteners in Pepsi Zero Sugar with sucralose, the active ingredient in the brand Splenda. This is likely due to the past market competition and product offerings. For a period, PepsiCo released variants like 'Diet Pepsi with Splenda' in certain markets, but sucralose is not a standard component of the main Pepsi Zero Sugar or Diet Pepsi formula.
Health and Safety Considerations
Both aspartame and acesulfame potassium have been extensively studied and approved as safe for consumption by major regulatory bodies around the world, including the U.S. Food and Drug Administration (FDA). The FDA establishes an Acceptable Daily Intake (ADI) level for each sweetener to ensure safety. However, ongoing debate and some studies have raised questions regarding the long-term metabolic effects of artificial sweeteners and their potential impact on gut health. Experts recommend that artificial sweeteners be consumed in moderation as part of a balanced diet. For official safety information on these ingredients, refer to the Food and Drug Administration (FDA) website.
Other Ingredients
Beyond the sweeteners, Pepsi Zero Sugar includes other components to create the full beverage experience:
- Carbonated Water: The base of the soda, providing fizz and texture.
- Caramel Color: Provides the characteristic dark brown color of cola.
- Phosphoric Acid and Citric Acid: Provide the tartness and act as a preservative.
- Natural Flavor: The proprietary flavor blend that gives Pepsi its distinct taste.
- Potassium Benzoate: A common preservative used to maintain freshness.
- Caffeine: A central nervous system stimulant.
- Calcium Disodium EDTA: A flavor protector that prevents flavor degradation.
Conclusion
Pepsi Zero Sugar is sweetened by a blend of artificial sweeteners, specifically aspartame and acesulfame potassium, which work synergistically to create its distinctive taste profile without any added sugar. While the core sweeteners have remained, ingredient formulations have seen tweaks over the years, particularly in different global markets and most recently in a US reformulation in 2023. It is distinct from Diet Pepsi, which offers a different taste experience due to slight variations in its formula. The sweeteners used are widely approved as safe for consumption within recommended limits, but like all processed foods, moderation is key for a healthy diet.
