What is the most sour candy in the world?

There's no single, universally agreed-upon "most sour candy in the world" because sourness is subjective and depends on individual taste sensitivity and the specific formulation of a candy. Different candies use varying combinations of acids (citric, malic, tartaric, etc.) and other flavor enhancers to create their sourness profile. Also, the intensity of the sourness can change depending on the size and concentration of the acidic compounds in a specific piece of candy.

However, some candies consistently rank highly on "sourness scales" created by candy enthusiasts or in online reviews:

• Warheads: This brand is often cited as one of the sourest, with various extreme sour versions released over the years. Their extreme sourness comes from a potent blend of citric acid and other acids.

• Toxic Waste: Similar to Warheads, Toxic Waste candies are known for their intense sourness. The packaging and branding often amplify the perceived level of sourness.

• Sour Patch Kids/Mega Warheads: While not always considered the absolute sourest, these candies boast significant sourness levels, often in a more manageable way compared to Warheads or Toxic Waste. They achieve this with a balance between sugary and sour flavors.

It's important to remember that the perception of sourness is individual. What one person finds unbearably sour, another might find mildly tart. The "most sour" title remains largely a matter of opinion and personal experience.