3rd century CE
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The plebeians and the army drank the posca, a drink despised by the upper class. The posca was made from acetum which was a low quality wine that almost tasted like vinegar. Sometimes wine that got spoiled (because it was not properly stored) would also be used to make this Roman drink.
Posca was made by watering down the low quality wine and by adding herbs and spices. It was drunk from the 300-200 BCE and into the Byzantine period (in the Byzantine army the drink was actually called the phouska). Recent studies have shown that posca was actually quite healthy. It was full of anti-oxidants and vitamin C, the coriander seeds had health benefits, and because it was quite acid (giving it its sour vinegar taste), it killed all the bacteria in the water, bearing in mind that water back then was not clean like our faucet water is today (or at least is in most western countries).
As we previously pointed out, posca was the drink of the common people and the upper class looked down on it. It was also the standard drink in the army. Drinking quality wine was considered impertinent in the military and sometimes standard wine was totally banned from army camps in the provinces.