Generation of non-protein nitrogen and volatile compounds by Penicillium chrysogenum Pg222 activity on pork myofibrillar proteins

A non-toxigenic strain of proteolytic Penicillium chrysogenum Pg222 isolated from dry-cured ham was tested for its ability to generate non-protein nitrogen (NPN) and volatile compounds from muscle myofibrillar proteins. The activity of mold led to higher accumulation of non-protein and amino acidic nitrogens than control samples. Volatile compound analysis revealed the presence of branched compounds, such as 3-methylbutanal and 3-methylbutanol only in samples inoculated with the mold. Similarly, compounds such as ethanol, propanol and 2-methoxy ethanol were detected only in inoculated samples at all sampling time. 3- and 2-methylpentane, benzoic and acetic acids, 2-butanone and 2-ethylhexanol, pyridine and 3-carene were detected occasionally, but only in the Pg222 batch. The proteolytic activity of P. chrysogenum Pg222 lead to accumulation of soluble NPN compounds, in addition to the generation of volatile compounds of great interest for dry-cured meat products. Therefore, this mold could be appropriate to be used as a non-toxigenic starter culture during the ripening of dry-cured meat products to stimulate proteolysis and flavour development.