# Characterization of Freisa Wines from Piedmont (Italy) by Aroma and Element Profile
## 1 Introduction  
In 2017 Freisa wine celebrated 500 years of history. The first official witness of this kind of wine dates back to 1517, in an official municipal price list. Among Italian red wines, Freisa is almost exclusively produced in the Piedmont region. Currently, five denominations of controlled origin (DOC) of Piedmont Freisa wines are recognized: Freisa di Chieri (hereafter indicated in the paper as FC), Freisa d'Asti (FA), Monferrato Freisa (MF), Langhe Freisa (LF), and Colli Tortonesi Freisa (CTF), which are related to the area of production. Although Freisa does not belong to the group of most famous \"noble\" Piedmont wines (such as Barolo and Barbaresco), it is gaining growing popularity among consumers also because of its versatility, since it can be vinitialed in different ways, ranging from sparkling to still and even sweet wines. Freisa wines are traditionally consumed young, and those that are subjected to aging represent a minor fraction. Information reported on the websites of the most important cellars indicates that fermentation and refinement are usually performed in steel or cement barrels. According to production regulations, the employment of wood barrels is not mandatory even for aged wines, which are often sold under the denomination 'Superior'. Nonetheless, most of the wines belonging to this category spend a variable period of time during refinement and/or aging in oak tasks, especially those of the Langhe Freisa DOC. Today, Freisa is cultivated over an area of about 850 hectares, with a year's production of 2.5 million bottles. In a demonstration of the growing interest in this kind of wine, some papers recently appeared in the literature regarding its characterization at various levels. The phenolic composition [1,2] and anthocyanins profile [1,3] of grapes wereinvestigated, as well as the genetic profile of the Freisa variety [4; 5]. Moreover, a recent paper appeared on the physicochemical characterization of Freisa grapes and wines [6]. Herein, the authors studied the mechanical features of berries and the phenolic content of grapes and wines, determining the standard chemical parameters (total acidity, alcohol content, dry net extract, etc.) of wines. Volatile compounds present in wine are mainly responsible for the so-called bouquet, i.e., the typical fragrance of wine. This results from the occurrence of hundreds of volatile compounds, which belong to different chemical families, including higher alcohols, fatty acids, esters, aldehydes, and terpen; their concentrations range from ng/L to mg/L. The volatile compounds profile may be obtained by gas-chromatography--mass spectrometry (GC-MS) after an extraction-pre-concentration step. Solid phase microextraction (SPME) is an extraction technique developed by [PERSON] and coworkers [7] and represents a valuable and highly reproducible tool for the extraction of volatile and semi-volatile analytes from different matrixes. The sample volume required is small, and the coupling with gas chromatography and mass spectrometry (GC-MS) provides high sensitivity. It has been widely employed for the study, among others, of many different food matrixes. In the headspace mode (HS-SPME), analytes are extracted from the gas phase, which is in equilibrium with the liquid sample. This avoids contamination of the fiber by non-volatile substances without lowering the sensitivity of the method. On the other hand, several mineral elements are present in wine at different concentrations, encompassing major elements such as Na, Ca, and P, minor elements (e.g., Fe, Na, Rb) and trace elements (e.g., Cu, Zn, Cr, Ni). Their content in wine is linked to several factors, the most important being the geographical origin of the wine, i.e., soil composition and, to a lesser extent, grapes and wine treatment and contamination [8]. Elemental analysis may be easily performed by several experimental techniques, such as atomic absorption spectroscopy and inductively coupled plasma optical emission spectroscopy (ICP-OES).