B2 any basic substance that is used in or produced by a reaction involving changes to atoms or molecules: The government has pledged to reduce the amount of chemicals used in food production. Each year, factories release millions of tons of toxic (= poisonous) chemicals into the atmosphere. More examples.
Queso blanco is traditionally made from cow's milk, whereas queso fresco may be made from a combination of cow's and goat's milk. They may both be eaten straight or mixed in with various dishes. Some versions of these cheeses, such as Queso Oaxaca, melt well when heated, but most only soften.
Queso Quesadilla. A soft, somewhat elastic-textured Mexican cheese made from cow's milk. It is white in color and has a very creamy flavor. It is a good grilling or pan-frying cheese as it becomes soft and pliable when heated, but does not melt and become runny. Queso Quesadilla is used as a snacking cheese, as a topping for melted cheese sandwiches and cheeseburgers, or as an ingredient for savory dishes and quesadillas.