Trivia

Hard

The Bulk Of The World’s Citric Acid Supply Is Created By?

Citrus Fruits
Chemical Synthesis
Industrial Waste Byproduct
Mold Byproduct
Black mold, Aspergillus niger, growing on an onion.
S. K. Mohan/Wikimedia

Answer: Mold Byproduct

It would be all too easy to think that the primary source of citric acid is citrus fruit—it is, after all, a rich natural dietary source of the nutrient—but despite how packed with citric acid some fruit might be (up to 8 percent of a lemon, by dry weight, can be citric acid), it’s not commercially viable to meet the world’s citric acid needs by extracting the compound from citrus fruit.

Although the very first industrial citric acid production, starting back in the 1890s in Italy, did extract citric acid from fruit, that process not only proved unsustainable in terms of global demand, but the outbreak of World War I led to the disruption of the industry and Italy’s hold on it.

By the early 20th century, a new method emerged when American food chemist James Currie discovered that certain strains of the fungus Aspergillus niger (a common contaminant of food that causes black mold)—seen here as you might find it in your kitchen growing on an onion—could produce large volumes of citric acid when fed a very sucrose or glucose (sugar) rich diet.

Despite scientific advances that allow for direct synthesis of citric acid (a technique invented in the 1970s), it’s far more cost effective to use mold cultures with the bulk of citric acid produced for both dietary and industrial use around the world being created by Aspergillus niger.

Trivia

Hard

What Is A Word That Belongs In The Dictionary But Isn’t?

Trivia

Very Hard

The First Feature Film To Be Completely Digitally Color Corrected Was?

Trivia

Hard

The Standard Galactic Alphabet From Commander Keen Also Appears In Which Of These Games?

Trivia

Very Hard

The Longest Song To Make It Into The Top 10 Billboard Hits Is?

Trivia

Hard

What Is The Longest Stop Motion Movie Ever Created?

Trivia

Hard

The Target Corporation Runs A State-of-the-Art Lab Devoted To What?

Trivia

Hard

Cryptographic Analysis Indicates The Man In The Iron Mask Was?

Trivia

Hard

Which Of These Liquids Is Considered The Most Expensive On Earth?

Trivia

Easy

The Sex Of Alligators Is Determined By?

Trivia

Hard

A Popular Sci-Fi Show Forced The U.S. National Park Service To Post Warning Signs Where?