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vestigation of the most represented basic muscle water-soluble proteins is suggested. Our method consists ofAcetic acid-Urea-Triton polyacrylamide gel (AUT-PAGE) analysis in the first dimension and standard sodiumdodecyl sulphate polyacrylamide gel (SDS-PAGE) in the second dimension. Although standard twodimensionalImmobilized pH Gradient-Sodium Dodecyl-Sulphate (2D IPG-SDS) gel electrophoresis has been successfullyused to study these proteins, most of the water-soluble proteins are spread on the alkaline part of the 2D map andare poorly focused. Furthermore, the similarity in their molecular weights impairs resolution of the classical approach.The addition of Triton X-100, a non-ionic detergent, into the gel induces a differential electrophoreticmobility of proteins as a result of the formation of mixed micelles between the detergent and the hydrophobicmoieties of polypeptides, separating basic proteins with a criterion similar to reversed phase chromatographybased on their hydrophobicity. The acid pH induces positive net charges, increasing with the isoelectric point ofproteins, thus allowing enhanced resolution in the separation. By using 2D AUT-PAGE/SDS electrophoresis approachto separate water-soluble proteins from fresh pork and from dry-cured products, we could spread proteinsover a greater area, achieving a greater resolution than that obtained by IPG in the pH range 3–10 and 6–11. Sarcoplasmicproteins undergoing proteolysis during the ripening of products were identified by Matrix AssistedLaser Desorption/Ionization–Time of Flight (MALDIToF) mass spectrometry peptide mass fingerprinting in aeasier and more effective way. Two-dimensional AUT-PAGE/SDS electrophoresis has allowed to simplify separationof sarcoplasmic protein mixtures making this technique suitable in the defining of quality of dry-curedpork products by immediate comparison of 2D maps to define the events occurring during their ripening and individuatecandidate molecular markers of the characteristic proteolytic processes. Considering that, essentially,muscle endogenous enzymic activity, calpains and cathepsins, occur in the ripening process of dry-cured ham,whereas a combined action between endogenous and microbial enzymes takes place in the case of sausage ripening,these results provide deeper insight into the respective role of endogenous and microbial enzymes in performingproteolysis. Finally, image analysis and creation of data bank could be achieved to quickly identify andprotect typical products.2. Nazzaro F., Fratianni F., Picariello G., Coppola R., Reale A., Di Luccia A. (2007). Evaluationof gamma rays influence on some biochemical and microbiological aspects in black truffles.Food Chemistry, 103: 344-354The effects of two gamma-ray doses (1.5 kGy and 2.0 kGy) on some biochemical aspects and on the microbiologicalprofile of black truffles was monitored, immediately after treatment and after 30 days of storage at 4 °C.Electrophoretic and chromatographic analyses of proteins and peptides, just like monitoring of polyphenol content,peroxides formation and microbial profile, allowed for the first time a better understanding of the mechanismsresponsible for biochemical alterations and bacterial pattern in black truffles during their storage. Treatmentat 1.5 kGy appeared to better preserve the characteristics of the fresh product. In 2.0 kGy-samples, the proteinprofile was characterised by a 20 kDa-polypeptide, which could be considered as an useful marker of the irradiationtreatment and of the storage time of the product. MALDI-TOF mass spectrometry analysis did not permita correct identification from tryptic peptides in databases, although the nano-ES/MS/MS analyses performedon the 10 kDa tryptic digest peptides showed an amino acidic sequence entirely contained in a protein of filamentousfungus Neurospora crassa.3. Faccia M., Gambacorta G., Caponio F., Pati S., Di Luccia A. (2007). Influence of type of milkand ripening time on proteolysis and lipolysis in a cheese made from overheated milk.International Journal of Food Science and Technology, 42: 427–433.A study was carried out in order to assess the influence of the type of milk and of the ripening time on the biochemicalchanges in Cacioricotta, a craft cheese manufactured from overheated milk. The features of the cheesewere strongly influenced by the peculiar cheese-making process, which is also characterized by absence of addedstarters and ‘forced drying’ in ventilated room. The electrophoretic patterns revealed heterogeneity of αs-casein,marked degradation of b-casein and slight hydrolysis of b-lactoglobulin in goat’s cheese, whereas presence of α-lactalbumin and strong hydrolysis of αs-casein were found in the ovine cheese. In spite of a significant primaryproteolysis, the ripening indices of matured cheeses were low, because of poor secondary proteolysis. Lipolysisproved to be the most significant biochemical event of ripening, and was strongly influenced by the type of milkused. The possible reasons of this particular ripening profile are discussed.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.it9