Certain molds on the surface of dry sausages are capable of forming mycotoxins that are harmful to humans and animals. The aim of this thesis was to evaluate the influence of a collagen casing on formation of AFB1 mycotoxin and the surface-to-interior diffusion of AFB1 in dry sausages. For this purpose, we designed a model system for ripening dry sausages, where the stuffing of dry sausages was applied to petri dishes. The content of AFB1 mycotoxin, that was formed on the surface by Aspergillus parasiticus ŽMJ7, was determined in the samples. The AFB1 content was measured in YES (Yeast Extract Sucrose Agar), in stuffing of dry sausages with no collagen casing applied and in stuffing with undamaged or damaged casing placed on top of it. Half of the samples were incubated using a temperature program for ripening sausages and the other half at 25˚C. ISOLUTE Myco columns were used for solid phase extraction (SPE) and the AFB1 content was determined by HPLC. The majority of AFB1 was formed in the first 7-14 days of the total 21 days of ripening. AFB1 began to form more rapidly in samples exposed to the temperature program for ripening sausages. There were no differences in AFB1 content between samples from the two different temperature groups in the later stages of ripening. The majority of AFB1 was formed in YES, significantly less was formed in the dry sausage stuffing without casing. The least AFB1 was determined in samples on which collagen casings were used. The presence of collagen barrier reduced the content of AFB1 in dry sausage stuffing by as much as 80-90%. This was not a result of collagen casing preventing the mycotoxin AFB1 from diffusing through the barrier into the interior of the sausage. The collagen casing by itself strongly reduced the overall formation of the mycotoxin. Approximately half of the AFB1 diffused from the surface into the stuffing through the collagen barrier. Damaging the casing did not affect the content of AFB1 in the stuffing of dry sausages.
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