Listeria lasts longer in the refrigerator than at room temperature.

The storage of cheeses and food safety are closely intertwined, particularly concerning various bacteria such as Listeria monocytogenes. Listeria not only poses serious problems in the food industry but also represents a direct threat to consumer health. This bacterium is particularly concerning in foods that have not undergone heat treatment, making proper storage and adherence to hygiene regulations critically important.

Storage Temperature and Salt Content

Storage temperature and salt content are essential factors regarding the shelf life of cheeses. Research shows that Listeria monocytogenes survives better at low temperatures than at room temperature, which sheds new light on cheese-making and storage practices. Reducing salt content has also been proposed as a potential method to limit the spread of bacteria; however, recent studies have shown that altering salt concentration does not affect bacterial behavior.

The Background of the Research

Research teams from the University of Córdoba and the University of Burgos jointly conducted investigations into the factors affecting the shelf life of soft and aged cheeses. The aim was to assess how storage temperature and salt content influence the proliferation of Listeria monocytogenes. Cheeses were tested at two different temperatures: 4°C (refrigerated) and 22°C (room temperature).

The results of the research were surprising: bacteria survived better in refrigerated environments than in cheeses stored at room temperature. This discovery warns that traditional storage methods may need to be reevaluated, particularly concerning soft cheeses, where the proliferation of Listeria may occur more rapidly.

Additionally, researchers found that reducing the salt content of soft cheeses between 1.17% and 0.30% did not affect bacterial behavior. This finding aligns with recommendations from the World Health Organization (WHO) aimed at reducing salt consumption. Therefore, the research provides important information not only for the scientific community but also for consumers regarding the safe storage of cheeses.

The Role of Salt Content in Cheese Safety

Salt content is a significant factor during cheese making and storage, as salt acts as a natural preservative and helps prevent bacterial proliferation. However, research shows that reducing salt does not necessarily correlate with an increased presence of bacteria.

In the case of soft cheeses, researchers observed that reducing salt concentration does not affect the proliferation of Listeria monocytogenes. This finding is particularly important because modern dietary recommendations often aim to reduce salt consumption. Thus, the results of the research offer manufacturers the opportunity to produce safe products even with reduced salt content, taking public health recommendations into account.

At the same time, it is important to note that different cheeses have distinct characteristics. While bacterial behavior may be favorable in soft cheeses, storage conditions are particularly critical for fresh cheeses, as these products are more prone to Listeria proliferation if not handled properly.

Cheese Production Practices and Safety

The practices employed during cheese production must strictly adhere to hygiene and safety regulations, which are essential in minimizing the risk of Listeria monocytogenes infection. In the European Union, cases of Listeria infections related to cheeses are continuously monitored, as the bacterium can pose a serious public health issue.

Although several cases of Listeria infections in cheeses have been reported in recent years, strict monitoring of manufacturing processes provides significant protection. To ensure food safety, manufacturers must continuously monitor hygiene standards and storage conditions of their products.

Cheesemakers must be aware that each type of cheese carries different bacterial risks. Fresh cheeses, in particular, require special attention, as these products can easily become contaminated if storage conditions change. Adhering to proper hygiene measures and strictly following food safety regulations are essential for producing safe and healthy cheeses.