Cotija cheese, often called the “Mexican Parmesan” due to its salty, dry, and crumbly texture, is a popular topping for many dishes. The safety of consuming Cotija cheese during pregnancy depends entirely on one factor: the method used to process the milk.
Understanding Foodborne Risks During Pregnancy
The primary concern with certain foods during pregnancy is the risk of contamination with the bacterium Listeria monocytogenes. This organism causes an infection known as listeriosis, which is a rare but severe foodborne illness. Pregnant individuals are uniquely susceptible to listeriosis because the immune system undergoes natural alterations to accommodate the developing fetus.
Pregnant women are estimated to be about 10 to 20 times more likely to contract listeriosis than other healthy adults. While the mother’s symptoms may be mild and flu-like, including fever, muscle aches, and nausea, the infection poses significant danger to the fetus.
The bacteria can cross the placenta, potentially leading to severe outcomes. Listeriosis consequences include miscarriage, stillbirth, or premature delivery. If the newborn is infected, they may suffer serious conditions like meningitis or sepsis. Because Listeria can grow even in refrigerated temperatures, it is a risk in ready-to-eat foods that are not reheated.
Determining the Safety of Cotija Cheese
The risk of listeriosis is most commonly associated with soft and semi-soft cheeses made from raw, or unpasteurized, milk. Traditionally, Cotija cheese is made from unpasteurized cow’s milk and aged, which means the traditional product poses a risk for pregnant individuals. However, most Cotija cheese sold commercially in the United States is produced using pasteurized milk.
To determine if a product is safe, check the packaging label. The label must state that the cheese was “Made with pasteurized milk” or “Pasteurized.” This process involves heating the milk to a specific temperature for a set time, which effectively kills Listeria monocytogenes bacteria.
If the pasteurization status is unknown, such as when purchasing from a deli counter or small artisanal producer, the cheese should be considered unsafe. Without clear labeling confirming pasteurization, the cheese must be avoided to eliminate the risk of listeriosis. This is especially true for cheeses imported from regions where pasteurization is not standard practice.
Practical Guidance for Consumption and Alternatives
If you are unsure of the pasteurization status or know the Cotija cheese was made with unpasteurized milk, you can still consume it safely by cooking it thoroughly. Heating the cheese to an internal temperature of at least 165°F will kill the Listeria bacteria. This temperature is typically reached when the cheese is added to hot dishes, such as baked enchiladas or soups, until it is steaming hot throughout.
For dishes requiring a crumbled cheese topping without cooking, several pasteurized alternatives mimic the texture and salty flavor of Cotija. Pasteurized feta cheese is a good substitute, offering a similar briny taste and crumbly consistency. Grated Parmesan cheese is another safe option; its hard, dry texture and low moisture content inhibit bacterial growth, and most commercial versions are pasteurized. Ricotta Salata is also a firm, salty, and crumbly cheese that can serve as a replacement.