Q.13.72 - An Introduction to General, Organic, and Biological Chemistry

Question

D-Erythritol is $70\%$ as sweet as sucrose and contains only hydroxyl functional groups. When D-erythritol is oxidized it forms D-erythrose. Draw the Fischer projection for D-erythritol. $(13.3,13.5)$

Step-by-Step Solution

Answer

• Erythritol is one of the most intriguing polyols since it has nearly no calories (EU: zero, USA: 0.2 kcal/g) and a clean sweet flavor with a relative sweetness of around 0.5. 
• Erythritol does not have the laxative adverse effects that other sugar alcohols have. 
• As a result, erythritol is a sugar-free bulk sweetener with relatively few calories.

Step 1: Introduction

• Erythritol is a sugar substitute included in many low-sugar and sugar-free goods. 
• It's made to take the place of sugar and calories in order to provide "diet-friendly" effects. 
• Powdered erythritol sweeteners are created by mixing and fermenting natural sugars in a manner that is almost equivalent to sugar. 
• Corn is commonly used to make the sweetener, although it may also be found naturally in foods like watermelon, soy sauce, and pears. 
• Fermented foods like cheese, as well as fermented drinks like wine and sake, are examples of such foods. 
• According to the FDA, it is classed as a carbohydrate and is used to provide sweetness, texture, and bulk to meals. 
• Browning and dryness are also prevented by the sweetener.

Step 2: Draw the structure of D-erythritol in Fischer projections.

• D-erythritol is a compound that is composed entirely of hydroxyl functional groups. It is used as a sweetener and is $70 \%$ sweeter than sucrose. D-erythrose can be formed when D-erythritol is oxidized.
• We know the structure of D-erythrose, which is a carbohydrate with four carbon atoms and an aldehyde group. 
• The aldehyde group can be formed from the hydroxy group by oxidation, which means that instead of the aldehyde group, D-erythritol will have a hydroxy group. 
• The rest of the molecule will be the same as D-erythrose.

Step 3: Continuation of draw the structure of D-erythritol in Fischer projections.

As we know from the problem, D-erythritol is a compound with only hydroxyl functional groups and can be oxidized to D-erythrose, which means that it has the following structure: