Shelf‐Life Extension of Fresh Tuber aestivum and Tuber melanosporum Truffles by Modified Atmosphere Packaging with Microperforated Films

Abstract

The aim of this study was to design a modified atmosphere packaging suitable for Tuber melanosporum and Tuber aestivum truffles that extend their shelf life and their availability as a fresh product. Their respiration rates were determined by O(2) depletion and CO(2) formation in closed systems performed at different temperatures: 4, 10, and 23 degrees C. The results were fitted by exponential equations and derivatives of these equations were used to obtain the experimental respiration rates. Our results revealed high respiration rates in both species of truffles and respiratory quotients (RQ) higher than 1 in all the cases studied. A linear dependence of respiration rate, both R(O2) and R(CO2), on O(2) concentration was revealed. A mathematical model was used to predict the evolution of the gaseous composition at 4 degrees C in the interior of polypropylene trays (250 mL) heat sealed with 4 microperforated films of different transmission rates. A microperforated film with 2 holes (90 x 50 microm) was selected to produce an internal atmosphere of 15%CO(2)/7%O(2) at 4 degrees C. The predicted atmosphere composition was confirmed by the experimental results. The quality and microbiological characteristics of fresh truffles, packaged in these conditions, revealed that the microbial counts of pseudomonads and Enterobacteriaceae were decreased, the weight loss was reduced, the typical hard texture was maintained, and the development of mycelium growth was delayed, enabling good scores for aroma and flavor, and therefore prolonging the shelf life of T. melanosporum and T. aestivum truffles to 28 and 21 d, respectively. Practical Application: This study describes the benefits of using MAP with microperforated films in the postharvest storage of Tuber melanosporum and Tuber aestivum fresh truffles. The shelf life of T. aestivum is prolonged to 21 d and of T. melanosporum to beyond 28 d increasing the possibilities for a foreign market.

Preservation of Truffles

“…Although truffles are sometimes eaten raw, current legislation does not establish limits for microbial counts or pathogen presence. The high initial microbial load and the presence of pathogenic microorganisms (Rivera, et al 2010) have created a need for early decontamination procedures (physical and/or chemical) that decrease the initial microbial population of truffles. Invasions of fungal pathogens, such as chestnut blight (Cryphonectria parasitica) and Dutch elm disease (Ophiostoma nova-ulmi), have resulted in devastating effects that are well documented (Desprez-Loustau et al 2007;Loo 2009).…”

“…Truffle quality was recently studied in relation with different postharvest technologies used to maintain them: canning (Coskuner and Ö zdemir 1997;Murcia et al 2002), modified atmosphere packaging (Kim et al 2006;Rivera et al 2010), freezing (Murcia et al 2002;Al-Ruqaie 2006;Saltarelli et al 2008) and irradiation (Akram and Kwon 2010;Nazzaro et al 2007;Rawi and Aldin 1979;Reale et al 2009;Rivera et al 2011). …”

Application of Modified Atmosphere Packaging on Quality of Selected Vegetables: A Review

“…A shelf life of 28 and 21 days was achieved for T. melanosporum and T. aestivum truffl es respectively stored at 4 °C under PMAP (a Mi-P fi lm was used) microbial load was reduced (2 and 1.2 log CFU/g reduction for mesophiles, 3.7 and 1 log CFU/g reduction for Enterobacteriaceae and 2.8 and 0.8 log CFU/g reduction for Pseudomonas on T. melanosporum and T. aestivum samples, respectively stored under MAP when compared with air stored samples) and texture and sensory characteristics (aroma, color) where better preserved on MAP samples (Rivera et al 2010 ).…”

Gene expression and metabolite changes during Tuber magnatum fruiting body storage

“…The aim of the present work was to monitor truffle quality, which is defined as a combination of several parameters (i.e., aroma, flavor, color, size, shape, appearance, and firmness; Hajjar et al 2010), during post-harvest conservation. Conservation is usually carried out by means of refrigeration (Saltarelli et al 2008), by irradiation (Nazzaro et al 2007;Reale et al 2009) or by modified atmosphere packaging (Rivera et al 2010), all of which lead to an extension of the shelf life and preservation of the truffle features (i.e., aroma, nutritional value). Some studies have been conducted to monitor the post-harvest quality of truffles.…”