Researchers have discovered three bottles of beer that are estimated to be 100-years-old in the Czech Republic, according to the DailyMail.

The lager type beer was so well-preserved that researchers were able to describe its original characteristics using chemical analyses.

They also tasted the beers and said they ranged from intensely sulfuric to sour, and had flavors that ranged from fecal to fruity.

The three lager beers apparently were produced during the World War I era and stored in a large cold cellar at the brewery, where they were gathering dust.

The beer, which was bottled in dark glass and well sealed, was discovered during the reconstruction of a brewery in Záhlinice, Czech Republic.

The researchers, based at the Research Institute for Brewing and Malting in Prague, Czech republic, decided to analyze the beer for insights into early 20th century brewing processes, as well as the chemical changes that occur in beer over long periods of time.

In their study, they wrote: ‘Because of the small volume of the century-old beer samples, sensory analysis was carried out by only five members of our sensory panel.

‘A descriptive analysis of flavor and taste was performed immediately after opening of the bottles’.

Following this, they conducted a chemical analysis to identify properties such as the original extract, alcohol content, colour and total acidity.

They used a method called high performance liquid chromatography as well as other techniques to compare the beers’ features to those of modern day brews.

The old beers had higher alcohol content and were less bitter than the beers of today.

They also contained more iron, copper, manganese and zinc.

The researchers also conducted a DNA analysis of the beer to identify any microorganisms present.

The first beer was ‘sensorially the least acceptable,’ according to the researchers.

‘It was light, hazy with very intensive sulphuric and fecal off-flavor,’ they wrote.