The activity carried out by the ancient guild of the formaggeri, known locally as casolini and throughout the Middle Ages as carnaroli or lardaroli, corresponds to that of present-day delicatessen shop-owners; on their premises, present in every square and district, customers could find butter, cheeses produced in the environs of Verona, Brescia and Lodi, pork, salami, fish preserved in either oil or brine, baccalà (i.e. salted codfish), candles, soap, rice, wax and a variety of oils. However, already back in the Fifteenth Century, a number of these merchants only sold olive oil. As well as that produced in the Garda region, they also sold oils purchased on the Venetian market. In order to be licensed oil merchants, the candidates had to sit an exam before a committee of experts, mostly elderly members of the guild, and as well as a variety of questions, they were asked to recognize the quality of various batches of oil by observing and smelling it. Nowadays the quality of an oil is guaranteed by the producer and the label on the bottle.