# The Inactivation of Microscopic Fungi in Bakery Products Using Hurdle Technology--A Case Study
## 4 Discussion  
Microscopic fungal growth can occur in the bakery environment, mainly in the air and on work surfaces, equipment, personnel, and ingredients, which can contaminate products after baking and ultimately contribute to food spoilage [12; 13]. [PERSON] et al. (2019); [PERSON] et al. (2005); [PERSON] et al. (2019 b), and [PERSON] et al. (2020) [13; 15; 16; 17] found mold in bakery air samples, where _Cladosporium_, _Aspergillus_, and _Penicillium_ genera predominated. However, few studies have focused on contamination control in bakery processing plants. Verifying mold contamination in the food industry involves a complex process. It is very important to study key environmental issues, such as hygiene related to microbiological air quality in factories [13] and contamination of food-contact surfaces [18]. Therefore, in the first stage of the study, microbiological analysis of the air and surfaces in the MAP drilling and packaging room of the manufacturing plant was carried out. The microbiological tests helped determine the level of contamination in the respective production areas. Based on the results obtained, the number of microscopic fungi in the air was found to range from 3.0 \(\times\) 10\({}^{1}\) to 1.6 \(\times\) 10\({}^{3}\) cfu/m\({}^{3}\). On the surfaces, on the other hand, the values were in the 3.1 \(\times\) 10\({}^{2}\)-6.8 \(\times\) 10\({}^{4}\) cfu/25 cm\({}^{2}\) range. The number of microorganisms tested in both rooms was therefore high, especially on the production surfaces. Figure 3: Appearance of products obtained with a starter containing **(1)**_L. plantarum_ and **(2)**_L. plantarum_ and _F. santrancisensis_ bacteria **(A)**—before packaging in MAP; **(B)**—in MAP packaging after storage; **(C)**—after storage and removal from packaging. Baked goods have a sterile surface after the baking process, and mold spores are inactivated during baking [19; 20]. Also, in the presented study, in all samples, regardless of the type of bread, after the half-baking process, the level of contamination with microscopic fungi was below \(10^{1}\) cfu/g. Further cooling, packaging, and slicing procedures, however, can quickly lead to the microbial contamination of products. Air, as well as contact with surfaces and equipment, is also often a source of contamination. This is confirmed by the results obtained, indicating a significant deterioration in the quality of bread after contact with the environment in the plant. The level of contamination, especially of hot dogs, increased to \(7.5\times 10^{2}\div 1.3\times 10^{3}\) cfu/g. This is not a high level compared to the data presented by [PERSON] et al. (2019 b), where the amount of mold in bread ranges from \(2.6\times 10^{7}\) to \(9\times 10^{8}\) cfu/g. However, it should be remembered that the tested products were intended for long-term storage, and what is more, molds are potential toxin-producing microorganisms. Also noteworthy is the fact that a ready-to-eat hot dog is not just the bread itself, but also cut, fresh vegetable. These ingredients are also very often highly contaminated [21]. Repeating the process of cutting such vegetables increases the number of bacteria, because the knife, contaminated during cutting, comes into contact with the vegetable several times. In the final product, the amount of microorganisms is therefore the sum of all contaminants and makes the product unfit for consumption. The reason for the increasing contamination of products after half baking is the poor quality of the production environment. Microscopic fungi present in the air and on production surfaces enter products both during the drilling and packaging processes. It is therefore important to prevent contamination after the baking process. Sanitary practices during the subsequent stages of production are of great importance here in particular. Mold causes not only changes in the color or taste of baked goods but also a loss of food quality due to the possible production of mycotoxins.