Aspartame (UK)

Aspartame is an artificial sweetener that is used as a substitute for sugar in numerous foods and beverages, especially in snacks and soft drinks. The reason that aspartame is frequently used is that it is close to 200 times sweeter than sucrose. In virtue of this quality, it has a strong sweeting effect with a much lower total number of calories compared to sucrose, which takes many more calories to obtain the same flavor.
The pronunciation of aspartame is different between British and American English.
In British English, the correct pronunciation of aspartame is uh-SPAR-tame.
The main difference in pronunciation between the two is where the stress is pronounced. In British English, the stress is pronounced on the second syllable, -SPAR. Since the stress is on the second syllable, the "a" in aspartame is pronounced as "uh" and the second syllable is pronounced as "spar". 
Differently from the British pronunciation, the American pronunciation of aspartame stresses the first syllable.
In addition, depending on accent and regionality, the "r" in -SPAR, may or may not be pronounced. In some cases, where the "r" is not pronounced, aspartame is pronounced as uh-spaa-tame.

Food and Beverage

English