# The Discovery of Aspartame as a Sugar Substitute

> This 1966 patent identifies specific chemical compounds, known as aspartylphenylalanine esters, that provide intense sweetness for food and drinks without using sugar.

- **Patent:** US 3492131
- **Original title:** Peptide sweetening agents
- **Owner:** GD Searle LLC
- **Granted:** 1970
- **Status:** Public domain (expired)
- **Times cited:** 228
- **Field:** biotech, pharmaceutical

## What it does

The patent claims a group of chemical compounds, specifically aspartylphenylalanine methyl ester and its related derivatives, which function as high-intensity sweeteners. These compounds are peptides, which are short chains of amino acids. By adding these substances to edible materials alongside a non-toxic carrier, the composition provides a sweet taste. The patent specifies that these compounds can exist in various stereochemical configurations, such as L-L or DL-L, to achieve the desired sweetening effect.

## What it does NOT cover

- Does not cover naturally occurring sugars like sucrose, glucose, or fructose.
- Does not cover non-peptide sweeteners such as saccharin or sucralose.
- Does not cover the specific manufacturing process for synthesizing these peptides, only the composition itself.

## The clever bit

The inventor discovered that by combining two specific amino acids—aspartic acid and phenylalanine—in a methyl ester form, he could create a compound hundreds of times sweeter than table sugar.

## Real-world examples

1. Diet Coke
2. Equal sweetener packets
3. Sugar-free chewing gum
4. Diet Pepsi

## Why it matters

This patent introduced aspartame to the world, which became one of the most widely used artificial sweeteners in history. It enabled the creation of the diet soda industry and provided a critical alternative for diabetics who need to manage blood glucose levels.

## Frequently asked questions

### What does The Discovery of Aspartame as a Sugar Substitute cover?

This 1966 patent identifies specific chemical compounds, known as aspartylphenylalanine esters, that provide intense sweetness for food and drinks without using sugar.

### Who owns patent US 3492131?

GD Searle LLC owns this patent, granted in 1970.

### When does this patent expire?

This patent has expired and is now in the public domain — anyone can use the invention freely.

### What is patent US 3492131 cited by?

This patent has been cited by 228 later patents that build on its ideas.

### What problem does this patent solve?

This patent introduced aspartame to the world, which became one of the most widely used artificial sweeteners in history. It enabled the creation of the diet soda industry and provided a critical alternative for diabetics who need to manage blood glucose levels.

### What does this patent NOT cover?

Does not cover naturally occurring sugars like sucrose, glucose, or fructose.

**Full plain-English explainer:** https://patentbrief.org/patent/us/3492131/aspartame-sweetener

**Original patent:** https://patents.google.com/patent/US3492131

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._


## Related patents

Semantically similar inventions in the PatentBrief corpus:

- [How Constantin Fahlberg Discovered Saccharin](https://patentbrief.org/patent/us/319082/saccharin-artificial-sweetener-fahlberg) — The 1885 patent for the chemical process to create saccharin, the first artificial sweetener, discovered by accident in a coal tar laboratory.
- [Chemical Compounds for Fighting Bacterial and Yeast Infections](https://patentbrief.org/patent/us/4147780/timoptic-timolol) — A 1977 patent for a specific class of amino-phosphonous acid chemicals designed to act as antibiotics against bacteria and yeast.
- [How Synthetic Peptides Block Immune System Overreaction](https://patentbrief.org/patent/us/10106579/orkambi-lumacaftor-ivacaftor) — A patent describing specific synthetic peptides designed to stop the body's immune system from attacking healthy cells by blocking a protein called C5.
- [Making Drug Proteins Last Longer and Target Diseases Better](https://patentbrief.org/patent/us/20190160160/methods-to-treat-diseases-with-protein-peptide-and-antigen-modification) — This patent describes ways to make protein and peptide drugs stay in the body longer and target specific diseases like autoimmune conditions or cancer more precisely by linking them together or combining them with other molecules.
- [How Computers Predict Protein Shapes Faster Using Smart Templates](https://patentbrief.org/patent/us/20210280268/protein-structure-prediction-system) — This patent describes a computer method to quickly predict the 3D shape of proteins by creating and refining "synthetic templates" from existing protein structures, reducing the heavy computational work usually needed.