Chemical and sensory effects of the freezing process on the aroma profile of black truffles (Tuber melanosporum)

Abstract

The aim of this work was to evaluate the effect of freezing black truffles (Tuber melanosporum) on their aroma both in sensory and chemical terms. The truffles were frozen at temperatures of -20 to -80°C. Descriptive and discriminative sensory and chemical analyses, based on headspace solid phase microextraction followed by gas chromatography-mass spectrometry analysis (HS-SPME-GC-MS), were carried out after 1, 20, 40 and 60 days. Fifteen compounds with high aromatic potential in truffles were determined. Their selective ion peak areas were calculated, summed and expressed as percentage of active odour compound, in order to monitor changes in odour profile. The aroma of frozen truffles differed significantly from the aroma of fresh truffles. Volatile composition data revealed that T. melanosporum aromatic profile is deeply modified as a consequence of a freezing process. These aromatic changes could explain the loss of freshness observed in all frozen truffles. Methional and some phenols were suggested as markers of freezing time. Interestingly, 1-octen-3-one appeared as a general marker of freezing process.

Does the host tree exert any influence on the aromatic composition of the black truffle (Tuber melanosporum)?

“…The volatile aromatic compounds shown in previous works to be relevant in the aroma of Tuber melanosporum have been analysed . Table shows the results expressed as average percentage areas, (% area), of the quantified aromatic compounds.…”

Truffle Research in the Post-Genomics Era

“…The aroma profile is commonly modified as a result of high-temperature processes or enzymatic reactions. The effect of storage and freezing on the volatile organic compounds (VOCs) profile, and subsequently on truffle aroma, has recently been reported (Culleré et al 2013;Pennazza et al 2013). Given that lyophilisation is performed at low temperatures, limiting the loss and degradation of volatile compounds, Palacios et al (2014) have recently tested it as a process for preserving truffles during storage.…”

Development of a robust HS-SPME-GC-MS method for the analysis of solid food samples. Analysis of volatile compounds in fresh raw beef of differing lipid oxidation degrees

“…Comparisons among samples of solid complex matrices are usually found using just raw areas (Machiels & Istasse, 2003;Perez, Rojo, Gonzalez, & De Lorenzo, 2008;Saraiva, Oliveira, Silva, Martins, Ventanas, & Garcia, 2015) or area percentages (Bergamini, Wolf, Perotti, & Zalazar, 2010;Cordero, Bicchi, & Rubiolo, 2008;R. Costa, Fanali, Pennazza, Tedone, Dugo, Santonico, et al, 2015;Cullere, Ferreira, Venturini, Marco, & Blanco, 2013). In the first case, there is no control over changes related to fibre adsorption-desorption or to detector sensitivity.…”