title: Proteolytic activity of Saccharomyces cerevisiae strains associated with Italian dry-fermented sausages in a model system.
abstract: Strains of Saccharomyces cerevisiae isolated from Italian salami were screened for proteolytic activity in a model system containing sarcoplasmic (SMS) or myofibrillar (MMS) proteins, at 20°C for 14days, to evaluate the possible influence on the proteolysis of fermented sausages. SDS-PAGE revealed that 14 of the most osmotolerant strains were responsible for the extensive hydrolysis of the main myofibrillar proteins, while only one strain was able to hydrolyze sarcoplasmic proteins. Free amino acids (FAA) accumulated during proteolysis were strain-dependent with different patterns from sarcoplasmic or myofibrillar protein fraction. In general, proteolysis lead Cys, Glu, Lys and Val as the most abundant FAA in the inoculated MMS samples. Volatile compound analysis, determined by SPME-GC-MS, evidenced 3-methyl butanol in MMS, and 2-methyl propanol and 3-methyl-1-butanol in SMS as major compounds. Our findings highlight that S. cerevisiae could influence the composition in amino acids and volatile compounds in fermented sausages, with a strain-dependent activity.
authors.affiliation: Dipartimento di Scienze degli Alimenti, Università degli Studi di Teramo, Mosciano Stazione (TE), Italy. chaves@unite.it
authors.forename: Clemencia
authors.initials: C
authors.lastname: Chaves-López
authors.forename: Antonello
authors.initials: A
authors.lastname: Paparella
authors.forename: Rosanna
authors.initials: R
authors.lastname: Tofalo
authors.forename: Giovanna
authors.initials: G
authors.lastname: Suzzi
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D005516:Food Microbiology / Q000706:statistics & numerical data*; D006868:Hydrolysis; D007558:Italy; D008461:Meat Products / Q000382:microbiology*; D000439:Pentanols / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D059748:Proteolysis; D012441:Saccharomyces cerevisiae / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D013552:Swine / Q000378:metabolism
chemical_list: D000596:Amino Acids; D000439:Pentanols; D011506:Proteins; C032765:tert-amyl alcohol