In Nicaragua, leche agria means “sour milk”.
In other words, the milk goes sour, due to the fermentation process triggered by the lactobacillus bacteria, which changes its taste and slightly its structure as well. So, leche agria is sour milk that reaches this stage in a natural manner, especially when left at room temperature, having a slightly sour taste and a more coagulated consistency. Some call this “spoiled milk”, especially when they are not accustomed to the product and taste, but leche agria contains nothing but good bacteria and can be consumed with no fear. In Nicaragua, leche agria is mostly served during breakfast, with a slice of bread or tortilla.