Abstract

The aim of the present work was to study the presence of interactions between volatile compounds and peptides and proteins from skeletal muscle using a recently extraction technique named solid phase microextraction (SPME). The purpose was to establish the effect of these interactions in the perception of dry-cured ham flavor. This study optimised the conditions for the application of solid phase microextraction (SPME) to the analysis of volatile compounds in dry-cured ham. It is necessary to take into account that many factors affect the extraction process as, the type of fibre, volatility and molecular mass of the volatile compounds. The extraction of the volatile compounds by different types of fibre was evaluated. The bipolar coatings Car/PDMS and DVB/Car/PDMS, were capable of extracting 70 different volatile compounds. Sixty compound were extracted by DVB/Car/PDMS fibre, whilst only 41 of then were found with CAR/PDMS fibre. In the study of interaction between volatile compounds with skeletal peptides (carnosine and anserine) and myoglobin the SPME technique was used. The interaction of carnosine with the volatile compounds was remarkable except for 2-pentanone. The peptide anserine showed interaction with 2-methylbutanal, 3-methylbutanal, hexanal and methional. Finally, myoglobin only presented interaction with 2-methylbutanal and hexanal. In all cases, the interactions followed the Scatchard's equation being no covalent and reversible. The effect of dry-cured agents in the interaction between volatile compound and muscular soluble peptides and proteins was studied. Ascorbic acid decreases the interaction for volatile compounds and carnosine. Finally, the effect of the dry-cured process parameters on the interaction between volatile compound and muscular soluble peptides and proteins was determined. The percentage of interaction is higher in the final stages of the dry-cured process in the presence of carnosine than in the presence of anserine and myoblobin. In conclusion, the results obtained demonstrate the presence of interactions between volatile compounds and muscular soluble protein compounds resulting in a modification of the relative proportion of these aromatic compounds in the headspace. The above mentioned modification can modulate the aroma and, consequently, change the sensory perception of the dry-cured ham.