When a woman is pregnant, many food safety questions arise, particularly concerning dairy products. Cotija cheese is a firm, salty, and crumbly Mexican cheese made from cow’s milk, often used as a topping for tacos, soups, and corn. Because of its traditional manufacturing methods and classification as a Mexican-style cheese, it requires specific safety considerations for expectant mothers. Determining whether this flavorful cheese is safe to consume requires examining its production process, as certain bacteria can pose a significant health concern.
Cotija Cheese and the Pasteurization Rule
The safety of Cotija cheese, similar to most fresh or soft cheeses during pregnancy, depends entirely on whether the milk used in its creation was pasteurized. Pasteurization is a process of heating milk to a specific temperature for a set time, which kills harmful microorganisms that may be present. Many Cotija cheese varieties sold in the United States are made with pasteurized milk, but traditional, imported, or artisan versions may still be made with unpasteurized, or raw, milk. The general rule for pregnant women is to avoid any cheese made from unpasteurized milk, and Cotija is no exception. To confirm safety, check the product label for the words “pasteurized milk” or “made with pasteurized milk.”
Why Unpasteurized Cheese Poses a Danger
The primary concern with consuming unpasteurized dairy is the presence of the bacterium Listeria monocytogenes, which causes the illness known as Listeriosis. Pregnant women are uniquely vulnerable to this infection, being about 10 to 20 times more likely to contract Listeriosis than the general healthy adult population. This heightened susceptibility is due to the natural suppression of the immune system during pregnancy.
Listeriosis can present with mild, flu-like symptoms in the mother, such as fever, muscle aches, or gastrointestinal issues, or it can even be asymptomatic. However, the bacteria can cross the placenta, leading to serious consequences for the developing fetus. These severe fetal risks include miscarriage, stillbirth, premature delivery, and potentially life-threatening infection of the newborn.
Safe Dairy Choices During Pregnancy
The general principle for consuming dairy during pregnancy is to select products made from pasteurized milk. This rule applies broadly to all milk, yogurt, and cheese products. Many hard cheeses, such as Cheddar, Swiss, and Parmesan, are inherently safe. This is because their low moisture and high acidity create an environment where Listeria struggles to survive. Processed cheeses, including cream cheese, cottage cheese, and commercially produced processed cheese spreads, are also safe when made with pasteurized milk.
Cheeses requiring caution include soft, mold-ripened varieties like Brie, Camembert, and blue-veined cheeses. Even if these are pasteurized, their high moisture content can still allow bacteria to grow. Mexican-style cheeses, including Queso Fresco, Panela, and Queso Blanco, also fall into this high-risk category if their pasteurization status is unknown. A practical way to eliminate the risk in any questionable soft cheese is to heat it until it is steaming hot, reaching an internal temperature of 165°F, which effectively kills the harmful bacteria.