Chemical Characterization of Craft Filuferru Spirit from Sardinia, Italy
Total Page：16
File Type：pdf, Size：1020Kb
beverages Article Chemical Characterization of Craft Filuferru Spirit from Sardinia, Italy Ilaria Langasco 1 ID , Marco Caredda 2, Gavino Sanna 1,* ID , Angelo Panzanelli 1, Maria Itria Pilo 1, Nadia Spano 1, Giacomo Petretto 3 and Pietro Paolo Urgeghe 3 ID 1 Department of Chemistry and Pharmacy, Sassari University, via Vienna 2, 07100 Sassari, Italy; [email protected] (I.L); [email protected] (A.P.); [email protected] (M.I.P.); [email protected] (N.S.) 2 Department for the Reseach on the Animal Production, Agris Sardegna, Loc. Bonassai, S.S. 291, Sassari–Fertilia, Km. 18,600, 07100 Sassari, Italy; [email protected] 3 Department of Agriculture, Sassari University, Viale Italia 39, 07100 Sassari, Italy; [email protected] (G.P.); [email protected] (P.P.U.) * Correspondence: [email protected]; Tel.: +39-079-229500; Fax: +39-079-0971-388 Received: 15 July 2018; Accepted: 16 August 2018; Published: 20 August 2018 Abstract: Traditional Filuferru is an ancient spirit from Sardinia, Italy, which is usually obtained from the distillation of wine or grape marc. In this contribution, the results of the first chemical characterization of a wide number of crafts Filuferru samples has been accomplished in terms of an evaluation of the alcoholic strength, qualitative and quantitative gas-chromatography–mass spectrometry (GC-MS) analysis of the volatile composition of the distillate, and its trace element composition by means an inductively coupled plasma–mass spectrometry (ICP-MS) method. Both instrumental methods have been validated and applied on 21 craft samples of Filuferru, whereas one sample of commercial distillate has been analyzed for comparison purposes. Alcoholic strength ranged between 41.0 and 62.4% (v/v). Sixty volatile compounds were identified and ten of them have been quantified. Analogies and differences with Grappa (i.e., the Italian distilled spirit closer to Filuferru) have been highlighted in the qualitative and quantitative profile of this matrix. Often meaningful amounts of acetaldehyde, ethyl acetate, dietyl acetal, and acetic acid were measured. Elemental analysis, performed on toxic, non-toxic elements, and oligoelements, 18 in total, revealed a wide variability of concentrations in both analytes and samples. High concentrations of Cu are sometimes evidenced, which are likely caused by losses from the distillation apparatus. The principal components analysis (PCA) allowed the differentiation of the ten volatile compounds quantified in two groups: the former, as described mainly by PC1, constituted by acetic acid, ethyl acetate, dietyl acetal, and acetaldehyde, and the second, described by PC2, constituted by 1-propanol, 2-methyl-1-propanol, the two coeluiting isomers 2-methyl-1-butanol and 3-methyl-1-butanol,1-hexanol, 2-phenylethanol, and 2,3-butanediol. Data obtained may be useful in order to establish a regulation for the production of high-quality traditional Filuferru from Sardinia. Keywords: Filuferru; spirit; distillation; grape marc; volatile compounds; copper; trace elements; GC-MS; ICP-MS; PCA 1. Introduction Traditional Filuferru is an ancient, high alcoholic strength beverage from Sardinia, Italy. For centuries, it is well-known and consumed by indigenous people not only as a beverage, but also as an ingredient in their traditional cuisine. Its artisanal manufacture took place in clandestine distilleries placed in domestic cellars or in the immediate neighbors of the vineyards, where usually wine (in the western side of Sardinia) or fermented grape marc (in the central or eastern side of the Isle) Beverages 2018, 4, 62; doi:10.3390/beverages4030062 www.mdpi.com/journal/beverages Beverages 2018, 4, 62 2 of 21 Beverages 2018, 3, x FOR PEER REVIEW 2 of 21 bottleswere distilled. of the product Since unauthorized in order to distillationoccult them was from prohibited inspections by law, that the were distillers made buriedby policemen, the bottles and of onlythe product a wire (i.e., in order Filuferru to occult in the them Sardinian from inspectionslanguage) tied that at were the neck made of by the policemen, bottle and andemerging only a from wire the(i.e., soilFiluferru levelin for the few Sardinian centimeters language) indicated tied at the the neckpoint of where the bottle the andvaluable emerging spirit from was the left. soil Craft level distillationfor few centimeters of Filuferru indicated is still today the point accomplished where the valuable by using spirit an internally was left. tinned Craft distillation copper pot of stillFiluferru with ais volume still today of usually accomplished between by 25 using and 100 an internallydm3. Figure tinned 1 represents copper a pot typical still withapparatus a volume for traditional of usually 3 batchbetween distillation. 25 and 100 dm . Figure1 represents a typical apparatus for traditional batch distillation. Figure 1. A typical pot still used for batch distillation of spirits. 1: Tinned copper pot; 2: still head; 3: Figure 1. A typical pot still used for batch distillation of spirits. 1: Tinned copper pot; 2: still head; 3: swan’s neck; 4: copper coil; and, 5: water cooling tank. swan’s neck; 4: copper coil; and, 5: water cooling tank. Heating of pot was accomplished by the combustion of wood or (preferably) liquid petroleum gas. WineHeating (or ofa potmixture was accomplishedof fermented bygrape the marc combustion and water) of wood is first or (preferably) fed in the pot liquid and petroleum then heated, gas. andWine great (or a care mixture was ofkept fermented in order grape to avoid marc overheating and water) isof first the fedcharge. in the The pot temperature and then heated, of the and vapors great measuredcare was kept on the in orderstill head to avoid is representative overheating ofof thetheir charge. chemical The composition, temperature ofand the this vapors information measured is usedon the by still the head distillers is representative in order to separate of their chemicalthe heart composition,of the distillate and from this the information head and is the used tail, by both the containingdistillers in toxic order and to separate unpleasant the heartsubstances, of the distillatelike methanol from theor headhigh-boiling and the organic tail, both compounds, containing respectively.toxic and unpleasant The heart substances, of the distillate like methanol was henc or high-boilinge condensed, organic giving compounds, rise to the respectively. final product, The normallyheart of the obtained distillate in a was single-sta hencege condensed, distillation giving step. riseTraditional to the final Filuferru product, is usually normally a colorless obtained spirit, in a whosesingle-stage aromas distillation recalled those step. of Traditional the winesFiluferru (or the grapis usuallye marc) a of colorless origin. spirit,Variants whose to the aromas pure distillate recalled arethose those of the aged wines or flavored (or the grape with marc)typical of spontane origin. Variantsous essences to the of pure Sardinia, distillate like are strawberry those aged tree or (flavoredArbutus Unedo with typical L.) fruits, spontaneous seeds of wild essences fennel, of Sardinia,or hot pepper. like strawberry Unlike Italia treen grappa (Arbutus (i.e., Unedo the L.)distilled fruits, spiritseeds by of grape wild fennel, marc technologically or hot pepper. most Unlike close Italian to Filuferru grappa) [1–6], (i.e., theto the distilled best of spirit our knowledge, by grape marc no scientifictechnologically publications most closeconcerning to Filuferru the chemical)[1–6], to characterization the best of our knowledge,of the main and no scientificthe trace composition publications ofconcerning traditional the Filuferru chemical are characterization until now published, of the main so the and principa the tracel aim composition of the present of traditional contributionFiluferru is to performare until the now qualitative published, and so thethe principal quantitative aim determination of the present contributionof both principal is to performand trace the constituents qualitative ofand this the ancient quantitative beverage. determination Hence, on ofa bothreliable principal sampling and of trace Filuferru constituents spirits distilled of this ancient by grape beverage. marc collectedHence, on by a reliablea number sampling of craft of Filuferruproducersspirits from distilled the Central by grape Sardinia, marc collected the alcoholic by a number strength, of craftthe chromatographicproducers from the qualitative Central Sardinia, profile, the alcoholicquantitative strength, determination the chromatographic of ten of the qualitativeprincipal volatile profile, compoundsthe quantitative beyond determination ethanol, and of the ten amount of the principal of 18 trace volatile elements compounds (i.e., Al, beyondB, Ca, Cd, ethanol, Cr, Cu, and Fe, theK, Mg,amount Mn, ofNa, 18 Ni, trace Pb, elements Sb, Sn, Sr, (i.e., W, Al,and B, Zn Ca,) have Cd, Cr,been Cu, measured Fe, K, Mg, and Mn, discussed. Na, Ni, Pb, Sb, Sn, Sr, W, and Zn) have been measured and discussed. 2. Materials and Methods 2.1. Samples 21 Filuferru samples produced from craft distillation of grape marc in eleven towns of central Sardinia (Figure 2) have been considered in this study. Beverages 2018, 4, 62 3 of 21 2. Materials and Methods 2.1. Samples 21 Filuferru samples produced from craft distillation of grape marc in eleven towns of central SardiniaBeverages 2018 (Figure, 3, x FOR2) have PEER been REVIEW considered in this study. 3 of 21 Figure 2. Geographical localization of the eleven towns