Question

Which of the following sugar has the highest sweetness?

• A. Invert sugar
• B. Sucrose
• C. Glucose
• D. Fructose

Hint:

Relative Sweetness Ranking: FRUCTOSE (173) $>$ Invert Sugar (125) $>$ Sucrose (100) $>$ Glucose (74) $>$ Galactose (32) $>$ Lactose (16, Least Sweet).

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Sensory sweet taste perception: D-fructose (fruit sugar ketohexose) exhibits the highest relative sweetness (173) among all naturally occurring dietary sugars compared to the sucrose baseline of 100.
Key Formula or Approach:
\[ \text{Relative Sweetness Scale: } \mathbf{D\text{-Fructose (173)}} > \text{Invert Sugar (120 - 130)} > \text{Sucrose (100 - Baseline)} > \text{Glucose (74)} > \text{Galactose (32)} > \text{Lactose (16)} \]

Step 2: Detailed Explanation:
Comparison of relative sweetness of sugars (standardized against Sucrose = 100 at $20^\circ ext{C}$):
1. D-Fructose (Levulose) (D): Has a relative sweetness of 173 (140 to 180), making it the sweetest naturally occurring carbohydrate. In cold solutions, it exists predominantly in the intensely sweet $\beta$-D-fructopyranose conformation.
2. Invert Sugar: Equimolar glucose + fructose (relative sweetness $\approx 120 - 130$).
3. Sucrose (Table Sugar): Relative sweetness = $100$ (Standard reference).
4. D-Glucose (Dextrose): Relative sweetness = $74$.
5. Lactose (Milk Sugar): Relative sweetness = $16$ (least sweet).

Step 3: Final Answer:
Hence, Fructose has the highest sweetness, matching option (D).