Which of the following artificial sweeteners have the highest sweetness value in comparison to sucrose ?

Correct — option (2), Alitame.

Alitame has a sweetness potency about 2,000 times that of sucrose (cane or table sugar). That is the figure in its specification from the Joint FAO/WHO Expert Committee on Food Additives (JECFA).

The other three are far weaker. The US Food and Drug Administration (FDA) gives sucralose about 600 times, saccharin 200 to 700 times, and aspartame about 200 times the sweetness of table sugar.

Alitame is a dipeptide-based sweetener, built from L-aspartic acid and D-alanine. JECFA allocated it an acceptable daily intake of 0–1 mg per kg of body weight.

Sweetness figures vary between sources, because they depend on concentration and how tasting is done. The gap here is wide enough that the ranking holds.

The idea to remember: at about 2,000 times sucrose, alitame is the sweetest of these four; aspartame sits near the bottom at about 200.

Why the others are wrong

• (1)
  Aspartame — Aspartame is about 200 times as sweet as table sugar, per the FDA, roughly a tenth of alitame's figure. It is the methyl ester of a dipeptide of aspartic acid and phenylalanine.

  Because it contains phenylalanine, it is unsuitable for people with phenylketonuria. On 14 July 2023, WHO's cancer agency IARC classified aspartame as possibly carcinogenic (Group 2B), while JECFA kept its acceptable daily intake at 0–40 mg/kg body weight.

• (3)
  Sucrolose — The option's "Sucrolose" is sucralose, a chlorinated derivative of sucrose in which three hydroxyl groups are replaced by chlorine atoms.

  The FDA puts it at about 600 times as sweet as table sugar, well short of alitame's 2,000. Sucralose is mostly heat-stable at normal baking temperatures, which lets it be used in baked foods.

• (4)
  Saccharin — Saccharin is 200 to 700 times as sweet as table sugar by the FDA's range. Even at the top of that range it is far below alitame's 2,000.

  Discovered in 1879 by Constantin Fahlberg at Johns Hopkins University, it is the oldest artificial sweetener among these options; aspartame, sucralose and alitame came in the second half of the twentieth century.

Artificial, or high-intensity, sweeteners taste sweet at tiny doses, so they add little or no energy to food. Their strength is expressed relative to sucrose, which is taken as 1.

The figures are approximate. They change with concentration, the food and the tasting method, so different sources give different numbers; the FDA's own range for saccharin runs from 200 to 700.

Chemically these sweeteners differ widely. Aspartame and alitame are dipeptide-based, sucralose is a chlorinated sugar, and saccharin is a synthetic compound unrelated to sugars.

Key facts

• JECFA's specification gives alitame a sweetness potency 2,000 times that of sucrose, and JECFA set its acceptable daily intake at 0–1 mg/kg body weight.
• The US FDA gives sucralose about 600 times, saccharin 200–700 times and aspartame about 200 times the sweetness of table sugar.
• Sucralose is made by replacing three hydroxyl groups of sucrose with chlorine atoms.
• Aspartame contains phenylalanine, so it is unsuitable for people with phenylketonuria.
• On 14 July 2023, IARC classified aspartame as possibly carcinogenic (Group 2B); JECFA kept its acceptable daily intake at 0–40 mg/kg body weight.

Common traps

• Sweetness figures vary by source. The FDA's range for saccharin (200–700) overlaps sucralose's 600, so ranking those two is unsafe; alitame's 2,000 is clear of both.
• "Sucrolose" in the option is sucralose. Its name echoes sucrose, but it is a chlorinated derivative about 600 times as sweet, not a natural sugar.
• Alitame is the sweetest only among the four options given. The FDA lists neotame at 7,000–13,000 times and advantame at about 20,000 times the sweetness of table sugar.

UnlockIAS will link similar questions from RAS Pre 2018 here once that paper is published on this site.

• practice — not a real PYQ

  Which of the following artificial sweeteners is a chlorinated derivative of sucrose?

  • (a)Aspartame
  • (b)Saccharin
  • (c)Sucralose
  • (d)Alitame
  Answer(3) — Sucralose is made by replacing three hydroxyl groups of sucrose with chlorine atoms. Options (1) and (4), aspartame and alitame, are dipeptide-based; option (2), saccharin, is a synthetic compound unrelated to sucrose.
• practice — not a real PYQ

  People with phenylketonuria are advised to avoid which of the following sweeteners?

  • (a)Sucralose
  • (b)Aspartame
  • (c)Saccharin
  • (d)Alitame
  Answer(2) — Aspartame contains phenylalanine, which people with phenylketonuria cannot break down properly. Option (1), sucralose, and option (3), saccharin, contain no phenylalanine; option (4), alitame, is built from aspartic acid and alanine and also lacks it.