ABSTRACT
Introduction ........................................................................................................ 671
Materials and Methods ..................................................................................... 672
Samples........................................................................................................ 672
DSC Analysis .............................................................................................. 672
Rheological Measurements....................................................................... 673
Analytical Determinations........................................................................ 673
Results and Discussion ..................................................................................... 673
References ........................................................................................................... 676
Balsamic vinegar, a typical product from the area of Modena and Reggio
Emilia in the north center of Italy dates back to the X to XI century. According
to Italian laws, traditional balsamic vinegar (Aceto Balsamico tradizionale di
Reggio Emilia, Italy), is obtained from natural sugar alcoholic fermentation
and acetic oxidation of unfermented, cooked, and concentrated crushed
grape (must) ($308Bx, according to Italian regulations) of the cv. Trebbiano,
Spergola, Lambrusco, and other local grape-wine varieties. This takes
place during long-term aging carried out in a series of small casks (vaselli)
made of different kinds of wood (mulberry, cherry, juniper) and with
progressively lower capacities. Every year the last and smallest cask of
the sequence provides a few liters of the final product, which are
compensated for by the product coming from the preceding barrel, and so
backward until the biggest ones where an amount of fresh must is added.
Generally, evaporation accounts for about 10% loss in volume per year; an
average of about 15 l of Traditionale can be obtained from 100 l of fresh must.
The traditional balsamic vinegar must be aged for at least 12 years but it is
possible to find some series of casks up to 100 to 200 years old. During the
process, microbial metabolism and natural evaporation induce a marked
increase in the concentration of derivatives of acetic fermentation, oxidation,
and Maillard reaction, which impart the typical sensorial characteristics to
the final product. Meanwhile, a change in some physical properties,
including density and viscosity, takes place (Mascolo, 1990; Giudici et al.,
1994; Meglioli et al., 1994; Anklam et al., 1998; Chiavaro et al., 1998; Del
Signore, 1998; Del Signore et al., 2000; Calabrese et al., 2002; Cocchi et al.,
2002; Zeppa et al., 2002).
