title: Application of a stir bar sorptive extraction method for the determination of volatile compounds in different grape varieties.
abstract: BACKGROUND
  Stir bar sorptive extraction (SBSE) has been employed for the analysis of aroma compounds directly from Spanish and Italian grape extracts. The extraction conditions have been optimized using a statistical approach, obtaining results that improve the current state of the art.
  
  
  RESULTS
  The proposed analytical conditions were: sample volume 40 mL, extraction time 80 min, 25% (w/v) NaCl and stirring speed 750 rpm using 20 mm × 0.5 mm stir bars. Performance characteristics of the SBSE procedure were further studied and showed correlation coefficients, detection and quantification limits, linear ranges, recoveries and precision values adequate for analysing these compounds in grapes. Twenty-four grape varieties (aromatic and non-aromatic) were analysed. Statistically significant differences (P < 0.05) according to geographical origin were found, being derived mainly from the terpenoid content. By principal component analysis it was possible to note that the terpenoids were more effective in the separation of the non-aromatic samples, showing negative and positive scores for Italian and Spanish grapes, respectively.
  
  
  CONCLUSIONS
  For non-aromatic grape varieties, the factor 'geographic location' was the most significant, thus corroborating the high influence of this parameter on the volatile composition of grapes and therefore on the genuineness of wines. © 2016 Society of Chemical Industry.
authors.affiliation: Life Sciences Department, BIOGEST-SITEIA, University of Modena and Reggio Emilia, 42122, Reggio Emilia, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Vasile-Simone
authors.affiliation: Analytical Chemistry Department, Faculty of Sciences, Andalusian Center of Wine Research (CAIV), University of Cádiz, Puerto Real, 11510, Cádiz, Spain.
authors.forename: Remedios
authors.initials: R
authors.lastname: Castro
authors.affiliation: Analytical Chemistry Department, Faculty of Sciences, Andalusian Center of Wine Research (CAIV), University of Cádiz, Puerto Real, 11510, Cádiz, Spain.
authors.forename: Ramón
authors.initials: R
authors.lastname: Natera
authors.affiliation: Life Sciences Department, BIOGEST-SITEIA, University of Modena and Reggio Emilia, 42122, Reggio Emilia, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Masino
authors.affiliation: Analytical Chemistry Department, Faculty of Sciences, Andalusian Center of Wine Research (CAIV), University of Cádiz, Puerto Real, 11510, Cádiz, Spain.
authors.forename: Carmelo G
authors.initials: CG
authors.lastname: Barroso
authors.affiliation: Analytical Chemistry Department, Faculty of Sciences, Andalusian Center of Wine Research (CAIV), University of Cádiz, Puerto Real, 11510, Cádiz, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Durán-Guerrero
mesh_terms: D000327:Adsorption; D018556:Crops, Agricultural / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D005163:Factor Analysis, Statistical; D005504:Food Analysis / Q000295:instrumentation / Q000379:methods*; D063427:Food Quality; D005638:Fruit / Q000737:chemistry* / Q000145:classification / Q000254:growth & development / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D007558:Italy; D057230:Limit of Detection; D015999:Multivariate Analysis; D009812:Odorants; D010860:Pigments, Biological / Q000032:analysis / Q000096:biosynthesis; D025341:Principal Component Analysis; D015203:Reproducibility of Results; D012677:Sensation; D013030:Spain; D013045:Species Specificity; D013499:Surface Properties; D013729:Terpenes / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D027843:Vitis / Q000737:chemistry* / Q000145:classification / Q000254:growth & development / Q000378:metabolism; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D004129:Dimethylpolysiloxanes; D010860:Pigments, Biological; D013729:Terpenes; D055549:Volatile Organic Compounds; C013830:baysilon
keywords: differentiation; experimental design; grapes; optimization; stir bar sorptive extraction; volatile compounds