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3. Maria De Angelis, Silvia de Candia, Maria Piera Calasso, Michele Faccia, Timothy P Guinee,Maria C Simonetti, Marco Gobbetti Selection and use of autochthonous multiple straincultures for the manufacture of high-moisture traditional Mozzarella cheese. Int J FoodMicrobiol. 2008 Jul 15;125(2):123-32.Lactobacillus plantarum 18A, Lactobacillus helveticus 2B, Lactobacillus delbrueckii subsp. lactis 20F, Streptococcusthermophilus 22C, Enterococcus faecalis 32C and Enterococcus durans 16E were the most acidifyingstrains within 146 isolates for natural whey starters. The effect of media and temperature on 2 autochthonousmultiple strain cultures (AMSI: 18A, 2B, 20F and 22C, 32C and 16E and AMSII: 18A, 2B, 20F and 22C) wasstudied. Genomic analysis showed a constant cell numbers for AMSII during 16 days of propagation in wheymilk. Mozzarella cheese was made by using AMSII, commercial starter (CS) or citric acid (DA). Compared toother cheeses, the DA had a lower level of protein, ash, Ca, free amino acids and a higher level of moisture.Based on confocal laser scanning microscopy analysis, AMSII cheese showed the lowest microstructural variationsduring the period of storage compared to other cheeses. All the sensory attributes were scored highest forAMSII cheese. ASMII extend the shelf-life to ca. 12−15 days instead of the 5−7 days of traditional highmoistureMozzarella cheese.4. A. Di Luccia, G. Picariello, A. Trani, P. Loizzo, M. Faccia, F. Addeo. Occurrence of Betacaseinfragments in cold-stored and curdled river buffalo (Bubalus bubalis L.) milk. Journal ofDairy Science. In press, proofs received.The safeguard of river buffalo Mozzarella cheese, a Protected Designation of Origin dairy product, has promptedanalytical study to devise a method to trace milk and curd raw matter in manufacturing to prevent the use of milkor curd from different geographical areas outside that used for river buffalo Mozzarella cheese production. Forthis purpose, we studied primary proteolysis occurring in fresh and frozen milk and curd to identify a molecularmarker that could indicate the raw matter used. Whole casein from frozen river buffalo milk was separated usingcation-exchange chromatography and sodium dodecylsulfate-PAGE, and a protein component with an estimatedmolecular weight of 15.3 kDa was detected. This protein component was revealed in fresh river buffalo milk as afaint electrophoresis band, which drastically increased in intensity in refrigerated and frozen milk as well as incurd and resulted linked to β-CN through hydrophobic interaction. By using matrix-assisted laserdesorption/ionization-time of flight peptide mass mapping, this component was identified as the C-terminalfragment (f)(69–209) of β-casein (expected molecular weight of 15,748.8 Da). β-Casein f(69–209), originatingfrom the early hydrolysis of Lys68-Ser69 by plasmin, has no counterpart in bovine milk. The increased rate ofhydrolysis by plasmin toward the cleavage site Lys68- Ser69 has to be ascribed to the elevated proline content ofthe peptide 61–73. The favored production of β-CN f(69–209) has also drawn attention to the complementaryproteose peptone β-CN f(1–68) that is presumed to play a physiological role in inducing milk secretion similar tothat of β-CN f(1–29). The higher in vivo and in vitro production rate, compared with γ1-CN formation, indicatesthat β-CN f(69–209) and its complementary fragment are candidate molecular markers to evaluate milk and curdfreshness. To perform a quantitative evaluation of proteolytic event was suggested an indirect ELISA analysisbased on the determination of intact β-CNSISTAL - 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.it13