Blue cheese is a delicious dairy product that can taste delicious but if you have it on your dinner table, you should be aware of the mold that is growing in it. The mold that grows in blue cheese can be very dangerous and can cause severe health problems.
Penicillium glaucum
Blue cheeses are a variety of dairy products that are typically aged for several months. During this time, the cheeses are made with a starter culture that turns lactose into lactic acid. This is also the source of the characteristic blue-green veins that appear in the cheese.
The mold spores that give the cheese its signature color and flavor are called Penicillium. These spores have been used for ages to make blue cheeses. Unlike other molds, the spores do not produce toxins that can harm humans. Instead, the mold spores produce interesting flavors and odors in the cheese. Some types of blue cheese can be eaten on their own, while others are often paired with other foods.
Penicillium glaucum is a popular option among blue cheeses. It is a blue mold that is often used to create Gorgonzola, a type of cheese produced in Italy. Gorgonzola is one of the oldest blue cheeses.
Generally, blue cheeses are made with starter cultures that are high in citrate-utilising bacteria. However, there are strains of Penicillium that can be harmful to humans. Therefore, it is important to know which penicillium is used to make blue cheeses.
Normally, a starter culture is added to raw milk before it is pasteurized. This is done to ensure that the curds are properly coagulated. After the curds are drained and the whey is released, Penicillium is sprinkled over the curds. During the aging process, the mould grows in the cheese and produces distinctive stains. Aside from the blue coloring, the mould also accelerates the breakdown of proteins and the production of anti-inflammatories.
The spores of Penicillium roqueforti are found in a variety of environments. They can grow in low temperatures and in areas with little oxygen. Since they are a common spoilage agent in a variety of food products, they are commonly used in blue cheeses. However, this doesn’t mean that the spores are dangerous. As a matter of fact, many people enjoy eating them.
In addition to the stains that appear in the cheese, the Penicillium roqueforti spores are also responsible for the famous flavor that comes from the cheese. The spores give the cheese a unique taste, with a sharp, salty, and sometimes sweet odor.
Most varieties of blue cheese are made with Penicillium roqueforti, but it is also possible to find some other species of penicillium in the cheese. In particular, the technological subspecies, P. roqueforti, is a more common mold spore in cheeses than the penicillium glaucum.
Although some strains of penicillium may be harmful to eat, the spores themselves are not toxic. This is because the spores are not inhaled. Nevertheless, it is important to remember that penicillium roqueforti is a spoilage agent in many dairy products.
As a result, the presence of penicillium roqueforti in cheese is widespread in nature. There are some commercial strains of the fungus that have been found to contain the compound Citrinin. Until now, however, the significance of the toxins has not been fully elucidated.
Lactobacillus plantarum
Lactobacillus plantarum is a widespread member of the genus Lactobacillus. It is widely used in food industries as a microbial starter. It has been shown to have anti-inflammatory, antidiabetic, and anticancer properties. These properties have been exploited to improve the quality and safety of fermented foods.
In this study, we investigated the effects of two probiotic strategies on the microbiome of feta cheeses. The first strategy was immobilization of a culture of L. plantarum on whey protein. This has been suggested as a way to maintain high probiotic cell loads and to ascertain the viability of the probiotic. We found that the presence of an immobilized culture had an effect on the abundance of lactic acid bacteria, particularly the lactobacilli, in the feta cheese. However, the levels of the lactobacilli in the feta cheese with immobilized cells were similar to those of the control feta cheese.
Another strategy was a challenge test in milk. After inoculating 107 cfu/g of milk with a solution of Ringer’s solution, we subcultured the cells in an MRS broth at 30 degC for 24 hours. Cultures were subsequently isolated by polymerase chain reaction – temperature gradient gel electrophoresis. Upon detecting the espece, we confirmed its identity by 16 s rRNA sequencing.
Despite the importance of identifying probiotics in the microbiome of feta cheese, there have been few studies investigating the effects of different probiotic strategies on the microbiome of this type of cheese. Thus, we conducted a study of the effects of immobilization and the challenge test on the microbiome of feta cheese. Our results showed that immobilization and a double inoculation of protective bacteria produced a different microbiome.
The results of the challenge test showed that the presence of an immobilized culture of L. plantarum on a whey protein reduced the viability of Streptococcus sp. after 16 days of storage. On the other hand, the presence of free L. plantarum T571 cells increased the abundance of lactobacilli in the feta-type cheese. The results also showed that the probiotic feta-type cheese exhibited an increase in the abundance of the genus Galactomyces.
During ripening, the counts of lactobacilli and enterococci grew. Leuconostoc lactis and S. thermophilus dominated the microbiome of DF cheese. But in the DF_2PL and 2PL cheeses, the protective lactobacilli increased the cell density of the thermophilic streptococci.
During storage, the levels of virulence factors were higher in Lb. plantarum B391 than in other Enteroccus isolates. Virulence factors included cytolisin, hyaluronidase, and gelE. Moreover, the bacteriocin B391 was heat-sensitive at pH values above 5.0 and remained stable at 121 degC. Furthermore, it showed antibacterial activity against L. monocytogenes B218.
Yeasts are important contributors to the flavor and texture of many types of cheese. They are also responsible for aroma formation. However, yeasts have been reported to be associated with the onset of ripening, affecting the appearance of the cheese.
Other microorganisms
The microflora of blue cheese consists of a variety of different organisms. These microbes contribute to the characteristic blue cheese flavor and appearance. Some are also present in the gut, producing a number of metabolites. However, the role of all microbes in cheese ripening and flavor is still unclear.
The Penicillium species form the core of the blue cheese flora. These organisms grow in the air spaces between curd particles. They are particularly adapted to low oxygen levels, making them a natural secondary starter culture for blue-veined cheeses. Many different species of Penicillium exist, containing over 300 distinct taxonomic units. While the majority of these species are known from cheese, they may be present in other forms of cheese, such as gouda, from caves and milk.
Several different species of yeast are found in blue cheese, such as Yarrowia lipolytica and Kluyveromyces marxianus. While some yeasts are important for flavor and texture of some cheeses, others can interfere with the taste and quality of other types of cheese. For example, some bacteria and molds may cause an off-flavor.
Another important part of the blue cheese microflora is the Penicillium camemberti. This obligate aerobe grows as a fluffy mass on the surface of Camembert and Brie cheese. It possesses a rapid adaptation process, characterized by changes in volatile compound profiles and reduced reproductive output.
Another important part of the microbial flora is lactic acid bacteria. These bacteria contribute to the production of lactic acid as the major end product in cheese. In addition to assisting with the coagulation of milk, these organisms also help with the acidification of cheese. During ripening, the lactic acid flora is replaced by enterococci. Although these organisms are not usually associated with blue cheese, the bacteria can have a positive influence on the taste of some types of cheese.
Other types of fungi are often present in blue cheeses. For example, Penicillium glaucum is responsible for the “blue” hue of some cheeses, while other genera of mold can be found in blue cheeses that are ripened in caves. Both bacterial and fungi interact with each other to produce aroma compounds, which are also key contributors to the flavor of blue cheese.
Microbial interactions are complex, and they can be competitive or cooperative. A combination of both can create a favorable microenvironment, allowing several different groups to survive on limited resources. By studying the relationship between the different microbial groups in a particular microbial community, it is possible to identify dominant populations and to determine the microbial relationships within them.
Biological interactions are mediated by a variety of molecular mechanisms, including the interaction of peptides, lipids, and protein breakdown products. In a microbial community, these interactions can affect the deacidification, ripening, and aroma formation processes.
