Fungal growth and mycotoxin production in a new formulated meat product with structured emulsions as substitutes for pork rigid fat

Abstract

One of the major changes in dietary habits of the last half-century has been the increase of meat-based products consumption. This increase has contributed to a diet rich in saturated fats, which can result in adverse health effects. A recent trend in food industry is the development of new meat products based on traditional ones, though having less saturated fats and adding healthy ingredients. In this work, the growth and mycotoxin production of three mycotoxigenic species that colonize meat products was evaluated in a new formulation of cured salami, where rigid pork fat was replaced by O/W structured emulsions based on sunflower oil. Together with the traditional formulation (TS), two degrees of rigid pork fat substitution were analysed, 50% (SF1) and total substitution (SF2). To evaluate fungal and mycotoxins contamination, salami produced in industrial environment were grinded and mixed with agar. This medium was inoculated with the toxigenic species Aspergillus nomius, Aspergillus westerdijkiae and Penicillium nordicum. At the end of the incubation period, fungal growth did not show significant differences between the three analysed samples for A. nomius; for P. nordicum results show a variation of approximately ± 10% of SF1 e SF2 in relation to TS; as for A. westerdijkiae SF1 and SF2 showed growth inhibitions up to 20% and 40%, respectively, when compared with TS samples. Despite fungal growth not being affected in the different, mycotoxin analysis revealed an almost complete inhibition of aflatoxin production by A. nomius in the SF2 medium and up to 90% for SF1, when compared with traditional salami. OTA production by P. nordicum was hindered by 15 to 30% for SF2 and up to 20% for SF1; and A. westerdijkiae OTA production was reduced by approximately 15%, in SF2 medium and up to 10% for SF1 medium, when comparing with traditional salami. Fatty acid profile shows a reduction of total fat of approximately 30% for SF1 and 60% for SF2, when compared with the traditional salami. More expressive differences are observed in palmitic, stearic, and oleic acid, where concentrations drop to half in SF2 samples. It is hypothesized that reduction of these fatty acids may be related to the reduced levels of mycotoxins, specially, in SF2 samples. Further studies are being developed to determine the factors responsible for mycotoxin inhibition in these new formulations.