Queso, a term encompassing various cheese dips and sauces, often raises questions about safety for pregnant people. Dietary restrictions during pregnancy aim to protect both the mother and the developing fetus from foodborne pathogens. Whether queso is safe depends entirely on the preparation and the type of cheese used. Understanding the source of the dairy and how it was processed determines if a particular queso is safe to consume.
The Critical Factor: Pasteurization
The fundamental rule for dairy consumption during pregnancy revolves around pasteurization. This process involves heating milk to a specific high temperature for a set time period, which eliminates harmful bacteria, including Listeria monocytogenes. The risk associated with certain cheeses is not related to fat content, but to the potential presence of these microorganisms. Pasteurization makes the resulting dairy product significantly safer for consumption. When milk is not pasteurized, it is considered “raw” and may naturally harbor pathogens. Any cheese made from raw milk carries an elevated risk of contamination, which is why pasteurization is the primary safety measure for dairy during pregnancy.
Categorizing Queso: Safe and Risky Varieties
Queso preparations fall into two main categories based on the type of cheese used. Generally safe options include processed, shelf-stable dips or restaurant-style queso made from hard or semi-soft cheeses like Monterey Jack or cheddar. These commercial products are almost always made with pasteurized milk, and the high-heat melting process provides an additional safety measure.
The risky varieties are those prepared with fresh, soft, or Mexican-style cheeses, such as queso fresco, queso blanco, or requesón. These cheeses are traditionally unaged and often made with unpasteurized milk, meaning they are more likely to harbor harmful bacteria. Pregnant people are specifically advised to avoid unheated queso fresco-type cheeses, even when they are made from pasteurized milk, due to the high risk of post-processing contamination.
Practical Steps for Determining Safety
When consuming queso outside of your home, take specific steps to confirm its safety status. If preparing queso at home, always check the ingredient label on the cheese for the word “pasteurized.” Most commercially sold cheeses in the United States are pasteurized, but imported or specialty soft cheeses may not be.
At a restaurant, ask the server directly about the cheese source used to make the queso dip. Inquire whether the dip is made from a processed cheese or a fresh cheese like queso fresco, and confirm that the cheese was made using pasteurized milk. If the queso is made with a high-risk cheese type, such as queso fresco, it must be cooked to a minimum internal temperature of 165°F (74°C) or until it is steaming hot to reduce the risk of contamination. When the pasteurization status cannot be confirmed, or if the cheese is a soft, fresh variety served cold, it is safest to avoid it entirely.
Understanding Listeriosis Risks
This careful approach is necessary due to the risk of Listeriosis, caused by the bacterium Listeria monocytogenes. Pregnant individuals are about ten times more likely to contract Listeriosis than the general population because of immune system changes during pregnancy. Symptoms in the mother are often mild and flu-like, including fever, muscle aches, or gastrointestinal upset.
Despite the mother’s potentially mild symptoms, the infection can pass to the fetus and result in severe complications. Listeriosis carries the potential for serious outcomes, including miscarriage, stillbirth, preterm delivery, or severe health problems for the newborn. The strict dietary guidelines concerning unpasteurized soft cheeses are a preventative measure to protect the fetus from this serious foodborne illness.