Las Meninas. Chemical Markers of Sensory Defects: The Role of Minor Components in Quality. Las Meninas

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1 Las Meninas Chemical Markers of Sensory Defects: The Role of Minor Components in Quality Ramón Aparicio Instituto de la Grasa (CSIC) Sevilla (Spain) ACS Long Beach, April 2012 Diego Rodríguez de Silva y Velázquez ( ) Painted in: 166 Museo del Prado (Madrid, Spain) Pablo Ruiz Picasso ( ) Painted in: 197 Museo Picasso (Barcelona, Spain) Las Meninas Are all the Chemical Compounds responsible for Virgin live il Sensory Quality? Researchers usually have three key questions to consider : Is there an underlying casual relationship? Do they smell/taste? Is the association merely a spurious correlation? Partial explanation? Is the association statistically significant? Strict validation? Association can be due to Confounding, Happenstance, Diego Rodríguez de Silva y Velázquez ( ) Painted in: 166 Museo del Prado (Madrid, Spain) CHEMISTRY Causal Pablo Ruiz Picasso ( ) Painted in: 197 Museo Picasso (Barcelona, Spain) SENSRY ASSESSMENT Causality. 1

2 Association can be due to: Confounding In Chemistry: V with high concentration of PPP indicates non freshly made just obtained V Association can be due to: Happenstance In Chemistry: A high content of 1,3 DAG indicates V with defects. PPP Freshness Scientific support: Time The 1,3-isomers are attributed to enzymatic or chemical hydrolysis of TAGs occurring before or during the oil extraction process. Also poor-quality olives show a significant increase of 1,3-isomers, and free fatty acids as well. Association can be due to: Happenstance In Chemistry: A high content of 1,3 DAG indicates V with defects. 1,3 DAGs Low Quality A negative sensory evaluation is usually the consequence of the combined effect of several sensory defects. Association can be due to: Causality There are four criteria: Consistency of association It s observed in all living beings Strength of association i Differences with and without aroma Temporal relationship Volatiles vary over time as aroma does Mechanism Plausible physiological and biochemical explanations Cum hoc ergo propter hoc with this, therefore, as a result of this 2

3 bjective Analysis of Aroma GMP Sensory Quality in Perspective: Stating the Problem lives lives Defective olives Processing Processing Inapropriate practices Identification and quantification of volatile compounds Causal Panel test Causal Sensor systems Probability 1.2 Md= Extra Virgin +Virgin Lampante Time, Tª, Light "Nothing is in the mind that did not first pass through the senses" -Aristotle. Analysis of flavour compounds bjective component DHS-GC (TENAX trap) SPME-GCMS (SPME fiber) GC-lfactometry Standardized method Long experience. Model to follow by other food products MS sensors SAW sensors DHS-MS Median of Defects Sensory evaluation Subjective component Black box Sensory Quality in Perspective: Stating the Problem Volatile Compounds: The RAD MAP Lampante Virgin live il Virgin live il Extra-Virgin live il ISLATIN CNCENTRATIN Vs ENRICHMENT F VLATILES SEPARATIN V not fit for consumption V with slight defects V without defects EV with unique qualifiers? Do we need a Hawk-Eye as well? IDENTIFICATIN SENSRY EVALUATIN SEPARATIN F CMPUNDS CHEMICAL STRUCTURE ELUCIDATIN F ARMA 3

4 counts m Instituto de la Grasa (CSIC), Seville, Spain Measuring Quality with Analytical Instruments Sensory Concepts Automatic HeadSpace with SPME - GC Preconcentration Sample amount (g) 2 Concentration 2 20 P1 C1 Tª (ºC) 40 Equilibrium Time (min) 1 Analytical instrumentation GC Varian CombiPAL Triple fiber SPME: DVB/CAR/PDMS R1 Internal standard: 4-Methyl-2-pentanol Adsorption Time (min) 40 Stirring Si Desorption Tª (ºC) 260 Desorption Time (min) Chromatographic conditions Injector Tª 260 ºC Detector Tª 280 ºC Carrier-gas H 2 Column 1 ml/min TRB-WAX (60m, 0.2mm, 0.2μm) Injector FID ven temperature program Tª (ºC) Ratio (ºC/min) Isotherm t (min) Total (min) SPME-GC-MS The sensory impact of the compounds does not depend on the concentration only! Sensory Concepts Sensory Concepts Concentration Concentration Why do small changes in flavour compounds have a major impact in perception? 1 Sensory Description Sensory Description 2 GC-lfactometry dour threshold h 1 = 00 x dour Threshold h 2 Small differences in quantification AV Major impact on sensory perception Sniffing Port Drawback: There is not a consensus about odor thresholds 4

5 Sensory Quality Estimation from live Paste Analysis Backward-tracing live Cleaning Crushing decanter olive oil Quality markers Ethyl propanoate Acetic acid Nonanal C6 (E-2-Hexenal, Hexanal) García-González, D.L.; Tena, N.; Aparicio (2007) Eur. J. Lipid Sci. Technol. 9, SPME-GC- Low quality High quality Explaining origin of olive oil defects by live il Aroma Markers live il Processing xygen, Time, Light Stickland reaction Defect ( Sensory descritor) Ketones, Marker of the defect (Volatile compounds) Aldehydes. Cause of the defect (Technological aspects) Cause of the defect (Biological aspects) Acids, Alcohols. live Health Quality Fungus, Yeast Temperature Extra-Virgin live il: Health olives ptimum ripeness Good Manufacturing Practices Adequate storage and bottling Shelf life Ethiology & live il Aroma Markers 1 SPME-GC No acids High content of C 6 esters Low content of alcohols High content of C and C 6 aldehydes (Biogenesis) live Cleaning Crushing decanter rigin: -Inadequate of lives in Transportation and/or prior to processing olive oil Fusty lives in an advanced stage of anaerobic fermentation 2-Methyl-1-propanol 3-Methyl -1-butanol Ethyl butanoate Propanoic acid Butanoic acid Aparicio & García-González; live il. In: Gourmet and Health-Promoting ils. Edited by A. Kamal-Erdin, R.A. Moreau ACS Press, 2009

6 Clostridium Pseudomonas Enterobacter Ethiology & live il Aroma Markers + Temperature and time, and without xygen 1 1 Fusty live Cleaning Crushing decanter rigin: - lives or paste in contact with dirty machinery olive oil Clostridium Stickland reaction D-Alanine Acetate H 2 NH + 4 HS-CA C 2 Pi HS-CA ADP ATP H - SCoA H H P - Pyruvate NH 2 Alanine Ferredoxin Phosphotranscetylase Acetate- Deshidrogenase xidorreductase Kinase Vinegary Winey Ethyl acetate Alcoholic fermentation of Acetic acid paste or damaged olives 3-Methyl-1-butanol Aparicio & García-González; live il. In: Gourmet and Health-Promoting ils. Edited by A. Kamal-Erdin, R.A. Moreau ACS Press, Alcoholic Fermentation Yeast (Candida, Pichia & Saccharomyces ) Acetobacteria + Temperature and time Ethiology & live il Aroma Markers 1 1 Fusty 1 Vinegary live Cleaning Crushing decanter olive oil rigin: - Unwashed lives collected with earth/mud or olives stored under humid conditions for days Acetobacteria Ethanol Acetaldehyde Acetic acid Musty Humidity Fermentation by fungi and yeasts Ethyl acetate Propanoic acid Acetic acid 1-cten-3-ol 2-Heptenol A-DH AL-DH Cytoplasm Aparicio & García-González; live il. In: Gourmet and Health-Promoting ils. Edited by A. Kamal-Erdin, R.A. Moreau ACS Press,

7 H H CH CH CH Instituto de la Grasa (CSIC), Seville, Spain Fermentation Fungus Humidity (Penicillium, Aspergillus) Temperature Yeast (Candida, Pichia and Saccharomyces) Time Ethiology & live il Aroma Markers Fusty Vinegary live Cleaning Crushing decanter olive oil rigin: - Inadequate storage conditions in tanks. Bottle storage conditions at supermarkets Linoleic acid -H- ctadienoic acid LX HPL 1 Musty Humidity Rancid Nonanal Hexanal ils undergoing autoxidation ctanal (hydroperoxide breakdown) Hexanoic acid (E)-2-Decenal cten-3-ol + 3-ctanone Reduction Aparicio & García-González; live il. In: Gourmet and Health-Promoting ils. Edited by A. Kamal-Erdin, R.A. Moreau ACS Press, 2009 xidation (autoxidation, thermoxidation) Temperature Time Ethiology & live il Aroma Markers 1 Light Cu, Fe, etc. Rancid live Cleaning Crushing decanter olive oil rigin: - il that have been left in contact with the sediment that settles in tanks and containers. leic acid Linoleic acid Linolenic acid Muddy Sediment Anaerobic fermentation of rest of solids and water. 6-Methyl--hepten-2-one 2-Butanol 2-Heptanol 1-Penten-3-one H 9-H -H 11-H 9-H 13-H 9-H 12-H 13-H 16-H 2-Undecenal Decanal 2-Decenal Nonanal ctanal 2,4-Decadienal 3-Nonenal Hexanal 2,4,7-Decatrienal 2,4-Heptadienal 27 3-Hexenal Propanal Aparicio & García-González; live il. In: Gourmet and Health-Promoting ils. Edited by A. Kamal-Erdin, R.A. Moreau ACS Press,

8 ur time is characterized by the perfection in the means and confusion in the objectives Albert Einstein live Cleaning Crushing decanter olive oil rigin: - Excessive temperature (T 3ºC) or prolonged heating time (t >60min) Heated Promotion of certain LX pathways over others (E)-2-hexenol Hexanol Nonanal Hexanal Pentanal Aparicio & García-González; live il. In: Gourmet and Health-Promoting ils. Edited by A. Kamal-Erdin, R.A. Moreau ACS Press, Ramón Aparicio, D.L. García-González, N. Tena, I. Romero, M.T. Morales, Jorge Vivancos, Instituto de la Grasa (CSIC) Seville, Spain (aparicio@cica.es) 8