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3. Dolci P., Alessandria V., Zeppa G., Rantsiou K., Cocolin L. (2008) Microbiological characterizationof artisanal Raschera PDO cheese: analysis of its indigenous lactic acid bacteria.Food Microb., 25, 392-399The aim of this research was to study the bacterial populations involved in the production of artisanal RascheraPDO cheese (Italian Maritime Alps, northwest Italy) in order to collect preliminary knowledge on indigenouslactic acid acteria (LAB). A total of 21 samples of Raschera PDO cheese, collected from six dairy farms locatedin the production area, were submitted to microbiological analysis. LAB were randomly isolated from M17 agar,MRS agar and KAA plates and identified by combining PCR 16S–23S rRNA gene spacer analysis, speciesspecificprimers and 16S rRNA gene sequencing. Biodiversity of Lactococcus lactis subsp. lactis isolates was investigatedby RAPD-PCR. LAB microflora showed the highest count values among all microbial groups targeted.They reached counts of 109 colony forming unit (cfu)/g in cheese samples after 3 days of salting and 15days of ripening. Yeast population also showed considerable count values, while enterococci and coagulasenegativecocci (CNC) did not overcome 107 cfu/g. L. lactis subsp. lactis was the species most frequently isolatedfrom Raschera PDO samples at all different production stages while in aged cheeses Lactobacillus paracasei wasfrequently isolated. RAPD-PCR highlighted that isolates of L. lactis subsp. lactis isolated from Raschera PDOwere highly homogeneous.4. Bertolino M., Zeppa G., Gerbi V., McSweeney P.L.H. (2008) Study of proteolysis in miniatureToma Piemontese cheese made using wild bacteria. Ital. J. Food Sci., 1, 20, 57-73The effects of 35 strains of indigenous bacteria on proteolysis in model Toma Piemontese cheese were studied at30 and 60 days of ripening. Proteolysis was assessed by urea-polyacrylamide gel electrophoresis (PAGE) of thepH 4.6-insoluble fractions of cheese, by reversed-phase high performance liquid chromatography (RP-HPLC) ofthe pH 4.6-soluble fractions at 30 and 60 days of ripening and by free amino acid (FAA) analysis at 60 days ofripening. Urea-PAGE showed that α s1 -casein was hydrolysed more than β-casein. The use of single strains markedlyinfluenced the peptide profiles obtained by RP-HPLC of the cheeses. Significant differences in the levels ofFAAs were also observed among the cheeses. The results of this study highlighted marked differences in theacidification and proteolytic activities of these bacterial strains.5. Dolci P., Alessandria V., Rantsiou K., Zeppa G., Cocolin L. (2008) Studio della microfloralattica del formaggio Castelmagno DOP con metodi coltura-dipendenti e coltura-indipendenti.Atti 8° Congresso Italiano di Scienza e Tecnologia degli Alimenti, Rho (MI), 7-8 Maggio2007, 301-305Lo scopo di questo lavoro è stato quello di studiare l’evoluzione della microflora lattica nel formaggioCastelmagno DOP. Da campioni di latte, cagliata e formaggio sono stati isolati 274 ceppi lattici successivamentesottoposti ad identificazione molecolare mediante le tecniche RSA (16S-23S rRNA gene spacer analysis), PCRspecie-specifica e sequenziamento del 16S. In parallelo è stata eseguita l’analisi DGGE (Denaturing Gradient GelElectrophoresis). Lactococcus lactis subsp. lactis è risultata la specie più frequentemente isolata durante lacaseificazione del Castelmagno DOP, mentre nel processo di stagionatura sono risultate prevalere le specieLactobacillus plantarum e Lactobacillus paracasei. In generale i risultati ottenuti dall’isolamento tradizionale supiastra hanno trovato corrispondenza con quelli ottenuti dall’analisi PCR-DGGE.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it460