|
|
Cheese defects and possible causes of their origin
Mazal, Marek ; Legarová, Veronika (advisor) ; Vladimír, Vladimír (referee)
This bachelor thesis is dealed with cheese defects and possible causes of their origin, which are participated in their formation. The problems of cheese defects is not focused only on technical apects, but it is also focused on microbial risks of possible contamination, the work is directed there at microbial quality of milk, which is crucial at the cheese manufacture. Microbial quality of milk is very important for cheesemaking, but the milk can be contaminated during the manufacture and also during the transport or storage. It is obvious for the reason of milk contamination, that milk has to be heat-treat, in order not to be damaged the final product. However heat-treat is not complete solution, because some microorganisms tolerate higher temperatures or they survive by formation of spores. Another way of contamination is entering of microorganisms during the cheesemaking, maturing and due to unsuitable storage. The cheese is not damaged only by microorganisms, but there are also significant physical factors, which can influence the quality of cheese, these are water activity, pH, salt content and temperature. These factors influence the natural microflora, which is present in the final product. However it is important realize, that there are differencies of susceptibility to forming pathogens among the cheeses, long aged cheeses are low risk due to it´s low pH, which prevents forming of pathogens so the pathogens can not endanger the cheese quality.
It should be considered suitable methods for elimination of pontecial risks and relevant defects during the cheesemaking. The most important methods should be regular hygien procedures, appropriate manufacturing and agricultural processes. The system of risk analysis and Hazard Analysis and Critical Control Points (HACCP) should be certainly present. For the prevention of cheese defect it is necessary regular control of specific paramaters at important stages of manufacture.
Very important matter is cosumption of cheese contaminated by mycotoxins, because consumption of mycotoxins is relatively high risk for human health. Mycotoxins are able penetrate into the cheese primarly due to presence of microscopic fungus, furthermore they can occur also as derivatives of mycotoxins, which are eaten by animals with their feed.
|
guest ::
