Food chemistry recall: among the common dietary sugars listed, which one is intrinsically the sweetest on a per-mass basis at room temperature?

Introduction:
Sensory sweetness varies by sugar type due to molecular structure and receptor interaction. Identifying the sweetest common sugar is a frequent exam item in food science and nutrition fundamentals.

Given Data / Assumptions:

• Sugars considered: glucose, fructose, sucrose, lactose.
• Standard conditions: aqueous solution, ~20–25°C.
• Relative sweetness scale using sucrose ~100 as reference.

Concept / Approach:
Fructose (levulose), a ketohexose, typically shows the highest relative sweetness (about 120–170 depending on conditions), exceeding sucrose and glucose. Lactose is the least sweet among the listed disaccharides/monosaccharides.

Step-by-Step Solution:
Compare typical relative sweetness: fructose > sucrose > glucose > lactose.Account for temperature dependence: fructose remains top under room temperature.Select fructose as the sweetest common dietary sugar.

Verification / Alternative check:
Food formulation references consistently rank fructose highest in sweetness intensity per gram under ambient conditions.

Why Other Options Are Wrong:

• Sucrose: sweet standard but generally below fructose.
• Glucose: significantly less sweet than sucrose.
• Lactose: least sweet of the group.

Common Pitfalls:
Assuming sucrose is always sweetest because it is the table sugar reference; in fact, fructose often exceeds it in sweetness, especially at lower temperatures.

Final Answer:
Fructose