Worldwide market screening of saffron volatile composition

Similar documents
One class classification based authentication of peanut oils by fatty

Effect of Different Drying Methods on Saffron (Crocus Sativus L) Quality

RESOLUTION OIV-OENO ANALYSIS OF VOLATILE COMPOUNDS IN WINES BY GAS CHROMATOGRAPHY

Analytical Method for Coumaphos (Targeted to agricultural, animal and fishery products)

Journal of Chemical and Pharmaceutical Research, 2017, 9(9): Research Article

Evaluation of ISO Method in Saffron Qualification

Evaluation of Quality Characteristics and Microbial Contamination of Saffron Samples Dried by Microwave

Detection of Artificial Red Colorants in Saffron Using UV-Vis Spectrometry and Tristimulus Colorimetry

Analytical Report. Volatile Organic Compounds Profile by GC-MS in Cupcake Batter Flavor Concentrate

Tyler Trent, SVOC Application Specialist; Teledyne Tekmar P a g e 1

Analytical Report. Volatile Organic Compounds Profile by GC-MS in Clove E-liquid Flavor Concentrate. PO Box 2624 Woodinville, WA 98072

Profiling of Aroma Components in Wine Using a Novel Hybrid GC/MS/MS System

Solid Phase Micro Extraction of Flavor Compounds in Beer

Determination of the concentration of caffeine, theobromine, and gallic acid in commercial tea samples

Determination of Caffeine in Coffee Products According to DIN 20481

Analytical Report. Table 1: Target compound levels. Concentration units are ppm or N/D, not detected.

Somchai Rice 1, Jacek A. Koziel 1, Anne Fennell 2 1

Table 1: Experimental conditions for the instrument acquisition method

Morphological Characteristics of Greek Saffron Stigmas from Kozani Region

Effect of Storage Time on Physiochemical and Microbial Properties of Saffron

GAS-CHROMATOGRAPHIC ANALYSIS OF SOME VOLATILE CONGENERS IN DIFFERENT TYPES OF STRONG ALCOHOLIC FRUIT SPIRITS

A novel approach to assess the quality and authenticity of Scotch Whisky based on gas chromatography coupled to high resolution mass spectrometry

Solid Phase Micro Extraction of Flavor Compounds in Beer

High-Resolution Sampling 2D-LC with the Agilent 1290 Infinity II 2D-LC Solution

Methanol (Resolution Oeno 377/2009, Revised by OIV-OENO 480/2014)

Fast Analysis of Smoke Taint Compounds in Wine with an Agilent J&W DB-HeavyWax GC Column

Somchai Rice 1, Jacek A. Koziel 1, Jennie Savits 2,3, Murlidhar Dharmadhikari 2,3 1 Agricultural and Biosystems Engineering, Iowa State University

Determination of Melamine Residue in Milk Powder and Egg Using Agilent SampliQ Polymer SCX Solid Phase Extraction and the Agilent 1200 Series HPLC/UV

EXTRACTION OF SEDIMENTS FOR AROMATIC AND CHLORINATED HYDROCARBONS

Identification of Adulteration or origins of whisky and alcohol with the Electronic Nose

Comprehensive analysis of coffee bean extracts by GC GC TOF MS

Analysis of Volatile Compounds of Jasminum nitidum [Acc.JN.1] Flowers

Acta Chimica and Pharmaceutica Indica

Novel Closed System Extraction of Essential Oil: Impact on Yield and Physical Characterization

Phytochemical composition of Moroccan saffron accessions by headspace solid-phase-microextraction

CHAPTER 8. Sample Laboratory Experiments

Comparison of Supercritical Fluid Extraction with Steam Distillation for the Extraction of Bay Oil from Bay (Pimenta Racemosa) Leaves

Bromine Containing Fumigants Determined as Total Inorganic Bromide

! " # # $% 004/2009. SpeedExtractor E-916

Application Note: Analysis of Melamine in Milk (updated: 04/17/09) Product: DPX-CX (1 ml or 5 ml) Page 1 of 5 INTRODUCTION

Determination of Pesticides in Coffee with QuEChERS Extraction and Silica Gel SPE Cleanup

Rapid Analysis of Soft Drinks Using the ACQUITY UPLC H-Class System with the Waters Beverage Analysis Kit

RIPENING OF WHITE CHEESE IN LARGE-CAPACITY BRINE TANKS

EXTRACTION. Extraction is a very common laboratory procedure used when isolating or purifying a product.

Determination of Methylcafestol in Roasted Coffee Products According to DIN 10779

The Benefits of GC/MS Coupled with a Headspace Trap to Monitor Volatile Organic Compounds in the Production of Beer

Development and characterization of wheat breads with chestnut flour. Marta Gonzaga. Raquel Guiné Miguel Baptista Luísa Beirão-da-Costa Paula Correia

AppNote 2/2003. Wine Discrimination using a Mass Spectral Based Chemical Sensor KEYWORDS ABSTRACT

5. Supporting documents to be provided by the applicant IMPORTANT DISCLAIMER

A COMPARATIVE STUDY OF THE CAFFEINE PROFILE OF MATURE TEA LEAVES AND PROCESSED TEA MARKETED IN SONITPUR DISTRICT OF ASSAM, INDIA.

Analysis of Volatile Compounds from the Concrete of Jasminum multiflorum Flowers

The Importance of Dose Rate and Contact Time in the Use of Oak Alternatives

EXTRACTION OF SEDIMENTS FOR BUTYLTINS

Agilent J&W DB-624 Ultra Inert Capillary Column Screens Distilled Spirits by GC/MS Static Headspace

Emerging Applications

PECTINASE Product Code: P129

TSKgel TECHNICAL INFORMATION SHEET No. 131

Evaluation of Soxtec System Operating Conditions for Surface Lipid Extraction from Rice

Influence of climate and variety on the effectiveness of cold maceration. Richard Fennessy Research officer

Extraction of Essential Oil from Citrus junos Peel using Supercritical Carbon Dioxide

FLAVOR CHARACTERIZATION OF THREE MANDARIN CULTIVARS (SATSUMA, BODRUM, CLEMANTINE) BY USING GC/MS AND FLAVOR PROFILE ANALYSIS TECHNIQUES ABSTRACT

[ application note note ] ]

High Sensitivity Quantitation Method of Dicyandiamide and Melamine in Milk Powders by Liquid Chromatography Tandem Mass Spectrometry

AppNote 4/2003. Fast Analysis of Beverages using a Mass Spectral Based Chemical Sensor KEYWORDS ABSTRACT

CHAPTER 8. Sample Laboratory Experiments

Extraction of Acrylamide from Coffee Using ISOLUTE. SLE+ Prior to LC-MS/MS Analysis

THE EFFECTS OF FIXED-BED DRYING ON THE YIELD AND COMPOSITION OF ESSENTIAL OIL FROM LONG PEPPER (Piper hispidinervium C. DC) LEAVES

Application Note FP High Sensitivity Coumarin Analysis. Introduction. Keywords

Quantitative Measurement of Sesquiterpenes in Various Ginger Samples by GC-MS/MS

Experiment 6 Thin-Layer Chromatography (TLC)

Optimization of pomegranate jam preservation conditions

Recent Developments in Coffee Roasting Technology

Determination of Ochratoxin A in Roasted Coffee According to DIN EN 14132

TOOLS OF SENSORY ANALYSIS APPLIED TO APPLES

Zoe Grosser, Vinson Leung, Jim Fenster, Brian LaBrecque Horizon Technology, Inc., Salem, NH USA

Elemental Analysis of Yixing Tea Pots by Laser Excited Atomic. Fluorescence of Desorbed Plumes (PLEAF) Bruno Y. Cai * and N.H. Cheung Dec.

Determination of natamycin in wines Résolution OIV-SCMA

Assessment of the CDR BeerLab Touch Analyser. March Report for: QuadraChem Laboratories Ltd. Campden BRI Group contracting company:

UNIVERSITY OF CALIFORNIA AVOCADO CULTIVARS LAMB HASS AND GEM MATURITY AND FRUIT QUALITY RESULTS FROM NEW ZEALAND EVALUATION TRIALS

Project Summary. Principal Investigator: C. R. Kerth Texas A&M University

Universidad, Gobierno de Aragón, Apdo. 727, Zaragoza, Spain e

The Determination of Pesticides in Wine

Varietal Specific Barrel Profiles

Determination Of Saponin And Various Chemical Compounds In Camellia Sinensis And Genus Ilex.

NEW ZEALAND AVOCADO FRUIT QUALITY: THE IMPACT OF STORAGE TEMPERATURE AND MATURITY

Proceedings of The World Avocado Congress III, 1995 pp

Effect of irrigation water salinity, manure application and planting method on qualitative compounds of saffron (Crocus sativus L.

Aromatic Potential of Some Malvasia Grape Varieties Through the Study of Monoterpene Glycosides

Chapter 1. Spices Sources, Processing, and Chemistry

EU Legal framework Wine Council Regulation (EC) 1234/207 integrating Regulation (EC) 479/2008 Commission Regulation (EC) 606/2006 Amendments of this r

Saffron Frauds in Jammu and Kashmir: Preliminary Organoleptic and Microscopic Investigation

distinct category of "wines with controlled origin denomination" (DOC) was maintained and, in regard to the maturation degree of the grapes at

Enhancing the Flexibility of the NGC Chromatography System: Addition of a Refractive Index Detector for Wine Sample Analysis

Investigating the factors influencing hop aroma in beer

ISO INTERNATIONAL STANDARD. Oilseed residues Determination of oil content Part 2: Rapid extraction method

Determination of Volatile Compounds in Romanian White Wines by Headspace Solid-phase Micro-extraction and Gas Chromatography Mass Spectrometry

Study on grinding of black pepper and effect of low feed temperature on product quality

Definition of Honey and Honey Products

Detecting Melamine Adulteration in Milk Powder

Transcription:

Research Article Received: 4 March 2009 Revised: 12 May 2009 Accepted: 14 May 2009 Published online in Wiley Interscience: 26 June 2009 (www.interscience.wiley.com) DOI 10.1002/jsfa.3679 Worldwide market screening of saffron volatile composition Luana Maggi, a Manuel Carmona, a C Priscila del Campo, a Charalabos D Kanakis, b Eirini Anastasaki, b Petros A Tarantilis, b Moschos G Polissiou b and Gonzalo L Alonso a Abstract BACKGROUND: Saffron (Crocus sativus L.) is one of the most valuable spices and nowadays its main use is as a foodstuff. Numerous papers have been published on saffron aroma and its volatile content, but nothing has been written about the aroma quality of samples available on the market to consumers. The aim of this study was to analyse and compare 418 commercial samples of saffron belonging to different ISO categories. Ultrasound-assisted extraction (USAE) with an organic solvent and dynamic headspace desorption (DHD) followed by gas chromatography/mass spectrometry were used to screen for saffron volatile composition. RESULTS: For both methods the saffron aromatic profile was characterised by spicy aromatic notes due to safranal, the most abundant volatile component, by a floral contribution attributable to isophorone and 2,2,6-trimethyl-1,4-cyclohexanedione, together with citrus and spicy notes from 4-ketoisophorone and 2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1-one respectively. CONCLUSION: USAE allowed the detection of a greater number of compounds, whereas DHD was faster and a smaller amount of saffron was required. Compared with the USAE method, the DHD method defined the samples as having a spicier and more floral aromatic contribution, thus corroborating that the extraction method considerably changes the aromatic fingerprint of saffron samples. c 2009 Society of Chemical Industry Keywords: aroma; saffron (Crocus sativus L.); GC analysis; ISO categories; volatile composition 1950 INTRODUCTION Saffron spice comes from the dried stigmas of Crocus sativus L. and nowadays its main use is as foodstuff. During the drying process the stigmas lose up to 80% of their weight, thus reducing the moisture content of saffron to 70 100 g kg 1. Important modifications have also been observed in terms of colour, 1,2 taste and aroma. 3 There are different drying processes depending on the country of production and therefore different characteristics and qualities of saffron. 1 By far the most important saffron-producing country is Iran (>90%), followed by Greece, Morocco, India, Spain and Italy. 4 The quality of saffron is determined by ISO 3632, 5 which classifies it into three categories according to physical and chemical parameters. Of these three parameters, colour has traditionally been the most appreciated, with aroma and taste only recently being noticed. On the international market, producers know that initially saffron has a wide variety of aromatic notes, some of which are lost and others of which become more intense and piercing over time. 6 In terms of the aroma chemistry of saffron, 2,6,6-trimethyl- 1,3-cyclohexadiene-1- (safranal) is the major compound together with 3,5,5-trimethyl-2-cyclohexene-1-one (isophorone), 2,6,6-trimethyl-2-cyclohexene-1,4-dione (4-ketoisophorone), 3,5,5-trimethyl-3-cyclohexen-1-one (an isomer of isophorone), 2,6,6-trimethyl-1,4-cyclohexadiene-1- (an isomer of safranal), 2,2,6-trimethyl-1,4-cyclohexanedione, 4- hydroxy-2,6,6-trimethyl-1-cyclohexen-1- (HTCC) and 2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1-one. 7,8 Some authors have reported the identification of more than 160 volatile compounds in saffron spice, though others have asserted that the number of these substances is not so high, since many of them could either be generated as artefacts when an exhaustive isolation procedures are employed. 9 The main techniques currently used to isolate saffron aroma 10 13 compounds are solvent extraction, distillation, including steam distillation and simultaneous distillation/extraction (SDE), 14 headspace techniques 3 and supercritical fluid extraction (SFE). 15 Some of these techniques seem to facilitate the extraction of several less important compounds (e.g. SFE) or to generate a large number of substances (e.g. SDE), but the best two extraction meth- Correspondence to: Gonzalo L Alonso, Cátedra de Química Agrícola, ETSI Agrónomos, Universidad Castilla-La Mancha, Campus Universitario, E-02071 Albacete, Spain. E-mail: Gonzalo.Alonso@uclm.es a Cátedra de Química Agrícola, ETSI Agrónomos, Universidad Castilla-La Mancha, Campus Universitario, E-02071 Albacete, Spain b Laboratory of Chemistry, Department of Science, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece J Sci Food Agric 2009; 89: 1950 1954 www.soci.org c 2009 Society of Chemical Industry

Worldwide market screening of saffron volatiles www.soci.org ods appear to be solvent extraction and headspace techniques. 9 Numerous papers have been published on saffron aroma and its volatile content, 9,14,16,17 but nothing has been written about the aroma quality of samples available on the market to consumers. The aim of this study was to analyse and compare 418 commercial samples of saffron belonging to different ISO categories. Ultrasound-assisted extraction (USAE) with an organic solvent and dynamic headspace desorption (DHD) followed by gas chromatography/mass spectrometry (GC/MS) were used to screen for saffron volatile composition. EXPERIMENTAL Samples Four hundred and eighteen saffron samples from Greece, India, Iran, Italy, Morocco and Spain belonging to different harvests (from 2004 to 2006) and commercial categories (according to ISO 3632 5 specifications) were collected for study (Table 1). The samples were obtained directly from the producers with a guarantee of origin and freedom from adulteration and were kept at 4 Cinthe absence of light until their analysis. All samples were analysed in duplicate using the two proposed methods. volume of the final aromatic extract in diethyl ether was 4 ml. The collected diethyl ether was analysed by GC to check if there was a loss of saffron volatiles during the evaporation procedure, but no saffron volatiles were detected. An HP 5890 Series II chromatograph (Hewlett Packard, Palo Alto, CA, USA) equipped with an HP 5972 mass-selective detector in electron impact mode (70 ev) and an HP-5MS capillary column (30 m, 0.25 mm i.d., 0.25 µm film thickness) with helium as carrier gas at a flow rate of 1 ml min 1 was used for the analysis of saffron aromatic extracts. The column temperature was initially held for 3 min at 50 C, then increased to 180 Catarateof3 Cmin 1 and finally increased to 250 Catarateof15 Cmin 1 and held for 5 min. The injector and detector temperatures were set at 220 and 290 C respectively. Samples (1 µl)were injectedmanuallyin splitless mode. For quantification of safranal the external standard method was applied. The calibration curve was established for the series of safranal standard solutions in diethyl ether, with the equation mg safranal kg 1 saffron = 86.6 Area safranal (R 2 = 0.999) where Area safranal = safranal peak area/10 6 in the GC chromatogram. Chemicals and reagents Safranal of 98% purity was obtained from Sigma-Aldrich (Madrid, Spain) as a standard. The solvents diethyl ether and cyclohexane were purchased from Panreac (Barcelona, Spain). Water was purified through a Milli-Q system (Millipore, Bedford, MA, USA). Series of safranal standard solutions in diethyl ether and cyclohexane were prepared and used to construct calibration curves for USAE/GC/MS and DHD/GC/MS respectively. A filtration membrane made of hydrophilic polytetrafluoroethylene (PTFE) with a porosity of 0.45 µm (Millipore) was used. Procedure and instrumentation USAE/GC/MS USAE was performed in a Super RK 255H ultrasound water bath (Sonorex, Berlin, Germany) at a fixed frequency of 35 khz. The temperature of the sonicated water bath was 25 C. The sample flask was charged with 4 g of saffron stigmas. The solvent system extractant was 40 ml of diethyl ether. Each saffron sample was sonicated twice for 15 min (two fractions per saffron sample). For each sonication a new volume of the solvent system extractant was added to the sample flask. The organic extract (80 ml) was concentrated using a Laborata 4000 Efficient rotary evaporator (Heidolph Instruments GmbH & Co.KG, Schwabach, Germany). The Table 1. Numbers of saffron samples from each country belonging to categories specified in ISO 3632 5 Country Category I Category II Category III Greece 112 10 0 India 2 0 0 Iran 101 48 8 Italy 60 0 0 Morocco 4 0 0 Spain 60 5 8 Total samples 339 63 16 DHD/GC/MS Ground saffron (10 mg) was placed in a stainless steel tube and DHD was carried out using a Perkin-Elmer TurboMatrix ATD thermal desorption system (Norwalk, CT, USA). The headspace isolation conditions were as follows: oven temperature, 50 C; desorption time, 5 min; cold trap temperature, 30 C; helium inlet flow rate, 45 ml min 1. The desorption unit was coupled to a Varian CP-3800 gas chromatograph (Palo Alto, CA, USA) equipped with a Saturn 2200 ion trap mass spectrometer provided with a VF-5MS Factor Four fused silica capillary column (30 m, 0.25 mm i.d., 0.25 µm film thickness) from Varian (Palo Alto, CA, USA). The column temperature was initially held for 2 min at 80 C, then increased to 200 Cat10 Cmin 1 and held for 5 min and finally increased to 250 Cat20 Cmin 1 and held for 5 min. The transfer line and detector temperatures were set at 230 and 300 C respectively. Helium was used as carrier gas at a flow rate 1 ml min 1.Inthe mass spectrometer the electron impact mode was set up at 70 ev. The mass range varied from 40 to 500 u. A calibration curve was constructed by injecting 10 µl aliquots of safranal standard solutions into stainless steel thermal tubes containing glass wool, previously conditioned for 1 min at 300 C under a nitrogen flow of 100 ml min 1. The quantification of safranal was again carried out using the external standard method. The calibration curve was established for the series of safranal standard solutions in cyclohexane, with the equation mg safranal kg 1 saffron = 10.88 + 36.76 Area safranal (R 2 = 0.998) where Area safranal = safranal peak area/10 6 in the GC chromatogram. Not all volatile compounds present in saffron are commercially available as standards, so safranal has been used as reference and other volatile substances have been compared against it. 1951 J Sci Food Agric 2009; 89: 1950 1954 c 2009 Society of Chemical Industry www.interscience.wiley.com/jsfa

www.soci.org L Maggi et al. 1952 Statistical analysis Evaluation of the statistical significance of differences was performed by analysis of variance (ANOVA) using the SPSS 15.0 for Windows statistical program (SPSS Inc., Chicago, IL, USA). Discriminant analysis was carried out with SPSS 15.0 for Windows to differentiate the saffron samples into the three ISO categories. RESULTS AND DISCUSSION According to the specifications of ISO 3632, 5 81% of the commercial saffron samples belonged to category I, 15% to category II and only 4% to category III. In Table 2 the main volatile compounds (expressed as g kg 1 total volatile content) found in the samples are reported, separated according to ISO category and analysis method. With respect to comparison of the two methods at first sight, USAE allowed for the determination of a higher number of volatile constituents, up to 22, while DHD only allowed for six, although other compounds were detected at trace levels. Safranal (compound 1), isophorone (compound 4), 2,2,6- trimethyl-1,4-cyclohexanedione (compound 5), 4-ketoisophorone (compound 7), 2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1- one (compound 9) and 2,6,6-trimethyl-1,4-cyclohexadiene-1- (compound 13) were the six main volatile compounds detected in all three categories using both methods. The total content of these compounds ranged between 540 and 630 g kg 1 for USAE, whereas it was almost 1000 g kg 1 for DHD. For both methods, analysis of the samples indicates that the major constituent of the aromatic composition of saffron is safranal, as reported previously. 7,18 In terms of saffron flavour chemistry, compound 1 has typical saffron spicy aromatic notes. 19 In terms of volatile composition screening of samples available on the market, with the USAE method the safranal content varied significantly between categories I, II and III, ranging from 336 to 429 g kg 1, whereas with the DHD method no significant differences were observed between the three categories, with levels similar to those ( 600 720 g kg 1 volatile fraction) reported by others. 7,14,20 The content of compound 4 was 87 g kg 1 for category I and decreased to 76 and 78 g kg 1 for categories II and III respectively with USAE, whereas DHD gave 188 g kg 1 for category I and 165 g kg 1 for categories II and III, confirming data ( 140 g kg 1 ) reported by Cadwallader. 19 For both methods, ANOVA did not allow us to separate the content of compound 4 between the three categories. Also, for compound 5 obtained by both USAE and DHD, there were no significant differences in its content between the three categories. With regard to saffron flavour chemistry, compounds 4 and 5 contribute to the aromatic profile of this spice with floral notes. 19,21 For USAE the content of compound 7 varied from 41 g kg 1 (category I) to 42 g kg 1 (category II) and 40 g kg 1 (category III), whereas for DHD it varied from 39 g kg 1 (category I) to 34 g kg 1 (category II) and 35 g kg 1 (category III). For both methods the levels obtained were in agreement with data ( 40 g kg 1 ) reported by Cadwallader 19 and there were no significant differences in the content of compound 7 between the three categories. Citrus aromatic notes have been attributed to compound 7 by Rödel and Petrzika. 21 The content of compound 9, characterised by spicy aromatic notes, 19 increased from 10 g kg 1 (category I) to 22 g kg 1 (category III) for USAE and from 21 g kg 1 (category I) to 28 g kg 1 (category III) for DHD. Also in this case there were no significant differences in the content of compound 9 between the three categories. The content of compound 13 decreased slightly from 6 g kg 1 (category I) to 3gkg 1 (category III) for USAE, while it increased from 31 g kg 1 (category I) to 41 g kg 1 (category III) for DHD. Again, for both methods there were no significant differences in the content of compound 13 between the three categories. With USAE the content of compound 2 was 153 g kg 1 for category I, 122 g kg 1 for category II and 163 g kg 1 for category III and it was possible to distinguish category II from categories I and III. The content of compound 3 decreased from 116 g kg 1 for category I to 66 g kg 1 for category III, showing significant differences between categories I and II and category III. The content of compound 6 increased from 51 g kg 1 for category I to 71 g kg 1 for category III, showing significant differences between the three categories. The content of compound 8 was 13 g kg 1 for category I, 7 g kg 1 for category II and 16 g kg 1 for category III, while that of compound 10 was 9 g kg 1 for category I, 10 g kg 1 for category II and 8 g kg 1 for category III. The content of compound 11 was 9gkg 1 for all three categories, whereas the content of compound 12 decreased from 7 g kg 1 for category I to 4 g kg 1 for category III. The contents of compounds 14 and 15 increased from 6 g kg 1 for category I to 44 g kg 1 for category III and from 5 g kg 1 for category I to 36 g kg 1 for category III respectively, so for both compounds there were significant differences between the three categories. The contents of compounds 16 and 17 ranged from 5gkg 1 for category I to 19 g kg 1 for category III and from 4gkg 1 for category I to 13 g kg 1 for category III respectively. In both cases it was possible to distinguish categories I and II from category III. The contents of compounds 18, 19 and 20 did not show significant differences between the three categories. Finally, compounds 21 and 22 were detected only for category I at 1 g kg 1. Furthermore, the 22 volatile components were used in a discriminant analysis to differentiate the saffron samples according to the three ISO categories (Fig. 1). The samples were clearly separated by two canonical discriminant functions, the first explaining 99.5% of the variance and the second explaining 100% of the accumulated variance. Compounds 2, 16 and 6 were observed as being the variables that contributed most to the differentiation in function 1, while compounds 6 and 16 contributed greatly to the differentiation in function 2. With regard to DHD, the mean contents of volatile compounds were not significantly different between ISO categories, which could be explained by the absence of sample handling. This confirms that saffron aroma has the same volatile fingerprint independently of its category, 20 which may be useful to detect adulteration of saffron aroma. Using USAE, significant differences in the volatile composition between ISO categories were observed, which could be explained by the ultrasound action that allows the isolation and detection of less volatile compounds of higher molecular weight. Also, the ultrasound water bath was operated at 35 khz, at which frequency no artefacts are produced. 14 Farmers produce saffron belonging to category I; subsequently, according to its postharvest treatment, saffron maintains its category or evolves to category II or III. As is known, saffron of the best quality belongs to category I not only for colour and flavour but also for aroma. USAE could be a good tool to distinguish ISO categories by means of the different contents of compounds 6, 14 and 15. As their contents increase, saffron aroma evolves negatively and its category worsens. Compounds 21 and 22 are quality markers for category I and therefore saffron containing these compounds is of higher quality. With respect to the sensory flavour profile, the data obtained corroborate that the extraction method considerably changes the aromatic fingerprint of saffron samples. www.interscience.wiley.com/jsfa c 2009 Society of Chemical Industry J Sci Food Agric 2009; 89: 1950 1954

Worldwide market screening of saffron volatiles www.soci.org Table 2. 3632 5 Main volatile compounds (expressed as g kg 1 total volatile content) of saffron samples belonging to categories I, II and III specified in ISO USAE (g kg 1 ) DHD (gkg 1 ) No. Compound Compound ions a (m/z) I II III I II III 1 2,6,6-Trimethyl-1,3- cyclohexadiene-1- (safranal) 2 4-Hydroxy-2,6,6-trimethyl-3- oxocyclohexa-1,4-diene- 1-3 4-Hydroxy-2,6,6-trimethyl-1- cyclohexen-1- (HTCC) 4 3,5,5-Trimethyl-2- cyclohexene-1-one (isophorone) 5 2,2,6-Trimethyl-1,4- cyclohexanedione 6 Isomerof 4-hydroxy-3,5,5-trimethyl- 2-cyclohex-1-one 7 2,6,6-Trimethyl-2- cyclohexene-1,4-dione (4-ketoisophorone) 8 Isomer of 4-hydroxy-2,6,6- trimethyl-3-oxocyclohex- 1-en-1 9 2-Hydroxy-4,4,6-trimethyl- 2,5-cyclohexadien-1-one 10 (E)-4-(2,2,6-Trimethyl-7-oxa- bicyclo[4,1,0]heptan-1- yl)but-3-en-2-one 107 (100), 91 (86), 121 (62), 150 (47) 109 (100), 137 (88), 123 (55), 180 (43) 107 (100), 135 (85), 79 (70), 168 (37) 82 (100), 138 (28), 54 (12), 95 (9), 41 (7) 139 (100), 56 (98), 42 (75), 154 (60) 98 (100), 70 (48), 69 (42), 154 (3) 68 (100), 96 (86), 152 (46), 109 (12) 43 (100), 41 (83), 153 (87), 182 (15) 109 (100), 124 (61), 152 (52), 137 (40) 123 (100), 111 (48), 168 (36), 208 (0.3) 11 Isophorone-4-methylene 107 (100), 91 (50), 108 (50), 150 (46) 12 Phenyl ethyl alcohol 91 (100), 92 (56), 122 (27), 65 (24) 13 2,6,6-Trimethyl-1,4-121 (100), 91 (50), 107 (40), cyclohexadiene-1-150 (8) (an isomer of safranal) 14 2-Hydroxy-3,5,5- trimethylcyclohex-2-en- 1,4-dione 15 4-Hydroxy-3,5,5-trimethyl-2- cyclohex-1-one 16 4-Hydroxy-2,6,6-trimethyl-3- oxocyclohex-1-en- 1 17 2,6,6-Trimethyl-3-oxo-1- cyclohexen-1-18 2,3-Dihydroxynapthalene- 1,4-dione 19 2,2-Dimethyl-cyclohexane- 1-20 3-[(E)-But-1-enyl]-2,4,4- trimethyl-cyclohex-2-enol 21 3,5,5-Trimethyl-3- cyclohexen-1-one (an isomer of isophorone) 22 2(3H)Furanone-dihydro-4- hydroxy 84 (100), 56 (80), 55 (59), 168 (44) 98 (100), 70 (58), 69 (39), 154 (7) 43 (100), 153 (87), 125 (87), 182 (15) 91 (100), 93 (83), 121 (77), 166 (28) 116 (100), 53 (69), 41 (46), 190 (7) 107 (100), 41 (40), 43 (36), 140 (12) 43 (100), 41 (69), 121 (62), 194 (11) 96 (100), 138 (78), 81 (75), 123 (65) 44 (100), 43 (68), 72 (24), 102 (9) 405 ± 32b 429 ± 36b 336 ± 27a 654 ± 66a 679 ± 61a 665 ± 64a 153 ± 14b 122 ± 8a 163 ± 21b 116 ± 17b 112 ± 19b 66 ± 16a 87a ± 11a 76 ± 13a 78 ± 14a 188 ± 21b 165 ± 18a 165 ± 19a 61 ± 7a 61 ± 8a 57 ± 10a 67 ± 6a 63 ± 7a 66 ± 5a 51 ± 5a 61 ± 4b 71 ± 5c 41 ± 16a 42 ± 11a 40 ± 13a 39 ± 10a 34 ± 7a 35 ± 3a 13 ± 2b 7 ± 1a 16 ± 3b 10 ± 2a 17 ± 4b 22 ± 2b 21 ± 5a 23 ± 3a 28 ± 2a 9 ± 1a 10 ± 2a 8 ± 1a 9 ± 1a 9 ± 1a 9 ± 2a 7 ± 2a 6 ± 1a 4 ± 2a 6 ± 2a 5 ± 1a 3 ± 2a 30 ± 9a 35 ± 7a 41 ± 6a 6 ± 1a 16 ± 2b 44 ± 12c 5 ± 1a 13 ± 2b 36 ± 10c 5 ± 2a 4 ± 1a 19 ± 4b 4 ± 1a 3 ± 1a 13 ± 3b 4 ± 1a 3 ± 1a 4 ± 2a 4 ± 1a 3 ± 2a 6 ± 2a 2 ± 1a 1 ± 1a 4 ± 2a 1 1 Different letters within a row indicate significant differences at the 0.05% level. Numbers in parenthesis denote mass abundance in the peak. a Ions used for compound identification. Bold type denotes ion selected for compound quantification. 1953 J Sci Food Agric 2009; 89: 1950 1954 c 2009 Society of Chemical Industry www.interscience.wiley.com/jsfa

www.soci.org L Maggi et al. Function 2 100 50 0-50 -100-100 1-50 2 0 Function 1 50 3 100 1 : category I 2 : category II 3 : category III Figure 1. Plot of canonical discriminant functions: according to ISO categories. CONCLUSION Four hundred and eighteen samples of saffron belonging to the three ISO categories were analysed using USAE with an organic solvent and DHD followed by GC/MS. The results were then compared to determine the screening of their volatile profile and to give an overview of world production. USAE allowed the detection of a greater number of compounds and differentiation of ISO categories, whereas DHD was faster, required a smaller amount of saffron and was able to characterise the saffron volatile fingerprint. Hence the aromatic profile of saffron available on the market to consumers was characterised by spicy aromatic notes due to compound 1, the most abundant volatile component, by a floral contribution attributable to compounds 4 and 5, together with citrus and spicy notes from compounds 7 and 9 respectively. ACKNOWLEDGEMENTS This work has been co-financed by the EC 6th Framework Programme for Research as a Research Project for the Benefit of SMEs Associations (SAFFIC COLL-CT-2006-030195-2). We thank the whole Project Consortium and the Project Officer Mr Valcárcel (German.VALCARCEL@ec.europa.eu) for their support and collaboration. REFERENCES 1 Carmona M, Zalacain Aramburu A, Pardo JE, López E, Alvarruiz A and Alonso Díaz-Marta GL, Influence of different drying and aging conditions on saffron constituents. JAgricFoodChem 53:3974 3979 (2005). 2 Bolandi M and Ghoddusi HB, Flavour and colour changes during processing and storage of saffron (Crocus sativus L.). Dev Food Sci 43:323 326 (2006). 3 Carmona M, Martínez J, Zalacain A, Rodríguez-Méndez ML, de Saja JA and Alonso GL, Analysis of saffron volatile fraction by TD GC MS and e-nose. Eur Food Res Technol 223:96 101 (2006). 4 Ghorbani M, The economics of saffron in Iran. Acta Hort 739:321 332 (2006). 5 ISO, Technical Specification. Saffron (Crocus sativus L.). Part 1 (Specification) and Part 2 (Test Methods). ISO 3632-1/2 (2003). 6 Carmona M, Zalacain A and Alonso GL, The aroma, in The Chemical Composition of Saffron: Color, Taste and Aroma, ed. by. Editorial Bomarzo SL, Albacete, pp. 123 124 (2006). 7 Tarantilis PA and Polissiou MG, Isolation and identification of the aroma components from saffron (Crocus sativus L.). J Agric Food Chem 45:459 462 (1997). 8 Winterhalter P and Straubinger RM, Saffron. Renewed interest in an ancient spice. Food Rev Int 16:39 59 (2000). 9 Carmona M, Zalacain A, Salinas MR and Alonso GL, A new approach to saffron aroma. Crit Rev Food Sci Nutr 47:145 159 (2007). 10 Zarghami NS and Heinz DE, Monoterpene aldehydes and isophoronerelated compounds of saffron. Phytochemistry 10:2755 2761 (1971). 11 Tarantilis PA, Polissiou MG and Manfait M, Separation of picrocrocin, cis trans-crocins and safranal of saffron using high-performance liquid chromatography with photodiode-array-detection. J Chromatogr A 664:55 61 (1994). 12 Sujata V, Ravishankar GA and Venkataraman LV, Methods for the analysis of the saffron metabolites crocin, crocetins, picrocrocin and safranal for the determination of the quality of the spice using thinlayer chromatography, high-performance liquid chromatography and gas chromatography. J Chromatogr A 624:497 502 (1992). 13 Loskutov AV, Beninger CW, Hostfield GL and Sink KC, Development of an improved procedure for extraction and quantitation of safranal in stigmas of Crocus sativus L. using high performance liquid chromatography. Food Chem 69:87 95 (2000). 14 Kanakis CD, Daferera DJ, Tarantilis PA and Polissiou MG, Qualitative determination of volatile compounds and quantitative evaluation of safranal and 4-hydroxy-2,6,6-trimethyl-1-cyclohexene-1- (HTCC) in Greek saffron. J Agric Food Chem 52:4515 4521 (2004). 15 Lozano P, Delgado D, Gómez D, Rubio M and Iborra JL, A nondestructive method to determine the safranal content of saffron (Crocus sativus L.) by supercritical carbon dioxide extraction combined with high-performance liquid chromatography and gas chromatography. J Biochem Biophys Meth 5:367 378 (2000). 16 Zougagh M, Ríos A and Valcárel M, Determination of total safranal by in situ acid hydrolysis in supercritical fluid media: application to the quality control of commercial saffron. Anal Chim Acta 578:117 121 (2006). 17 Du H, Wang J, Hu Z and Yao X, Quantitative structure retention relationship study of the constituents of saffron aroma in SPME GC MS based on the projection pursuit regression method. Talanta 77:360 365 (2008). 18 Alonso GL, Salinas MR, Esteban-Infantes FJ and Sánchez- Fernández MA, Determination of safranal from saffron (Crocus sativus L.) by thermal desorption gas chromatography. J Agric Food Chem 44:185 188 (1996). 19 Cadwallader KR, Flavor chemistry of saffron, in Carotenoid-derived Aroma Compounds, ed. by Winterhalter P and Rouseff RL. ACS Symposium Series 802, Washington, DC, pp. 220 239 (2002). 20 Alonso GL, Salinas MR and Garijo J, Method to determine the authenticity of aroma of saffron (Crocus sativus L.). J Food Protect 61:1525 1528 (1998). 21 Rödel W and Petrzika M, Analysis of volatile components of saffron. JHighResolChromatogr14:771 774 (1991). 1954 www.interscience.wiley.com/jsfa c 2009 Society of Chemical Industry J Sci Food Agric 2009; 89: 1950 1954