Citric acid is a weak organic tribasic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in the metabolism of all aerobic organisms.
More than a million tons of citric acid are manufactured every year. It is used widely as an acidifier, as a flavoring, and as a chelating agent.
Citric acid exists in greater than trace amounts in a variety of fruits and vegetables, most notably citrus fruits. Lemons and limes have particularly high concentrations of the acid; it can constitute as much as 8% of the dry weight of these fruits (about 47 g/L in the juices). The concentrations of citric acid in citrus fruits range from 0.005 mol/L for oranges and grapefruits to 0.30 mol/L in lemons and limes. Within species, these values vary depending on the cultivar and the circumstances in which the fruit was grown.
Industrial-scale citric acid production first began in 1890 based on the Italian citrus fruit industry, where the juice was treated with hydrated lime (calcium hydroxide) to precipitate calcium citrate, which was isolated and converted back to the acid using diluted sulfuric acid. In 1893, C. Wehmer discovered Penicillium mold could produce citric acid from sugar. However, microbial production of citric acid did not become industrially important until World War I disrupted Italian citrus exports.
You were right, you were bigger than me
I no longer see the sun, you have eclipsed it
When you left you reflected back the light
The glow of a million creatures with hope burning bright
I will wait for you a thousand years
You retrograde like planets slipping backwards
I will wait for you a thousand more
One thousand promises, one thousand last goodbyes
You were right, you were better than me
I've broken all my mirrors so you can't see what you've done to me
I am yours forevermore
I will wait for you a thousand years
A thousand promises, one thousand last goodbyes
I will wait for you a thousand more
You retrograde like planets slipping backwards, slipping backwards
You were right
You were right
You were right
You were right
I will wait for you a thousand years
You retrograde like planets slipping backwards
I will wait for you a thousand more
One thousand promises, one thousand last goodbyes
A thousand last goodbyes
You were right