title: Retention of aroma compounds: an interlaboratory study on the effect of the composition of food matrices on thermodynamic parameters in comparison with water.
abstract: BACKGROUND
  Partition coefficients give an indication of the retention of aroma compounds by the food matrix. Data in the literature are obtained by various methods, under various conditions and expressed in various units, and it is thus difficult to compare the results. The aim of the present study was first to obtain gas/water and gas/matrix partition coefficients of selected aroma compounds, at different temperatures, in order to calculate thermodynamic parameters and second to compare the retention of these aroma compounds in different food matrices.
  
  
  RESULTS
  Yogurts containing lipids and proteins induced a higher retention of aroma compounds than model gel matrices. The observed effects strongly depend on hydrophobicity of aroma compounds showing a retention for ethyl hexanoate and a salting out effect for ethyl acetate. A small but noticeable decrease in enthalpy of affinity is observed for ethyl butyrate and ethyl hexanoate between water and food matrices, suggesting that the energy needed for the volatilization is lower in matrices than in water.
  
  
  CONCLUSIONS
  The composition and complexity of a food matrix influence gas/matrix partition coefficients or aroma compounds in function of their hydrophobicity and to a lower extent enthalpy of vaporization.
authors.affiliation: Institut National de la Recherche Agronomique, UMR 1129 FLAVIC, Dijon, France.
authors.forename: Mirela
authors.initials: M
authors.lastname: Kopjar
authors.forename: Isabelle
authors.initials: I
authors.lastname: Andriot
authors.forename: Anne
authors.initials: A
authors.lastname: Saint-Eve
authors.forename: Isabelle
authors.initials: I
authors.lastname: Souchon
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Guichard
mesh_terms: D000085:Acetates / Q000737:chemistry; D002087:Butyrates / Q000737:chemistry; D002208:Caproates / Q000737:chemistry; D004041:Dietary Fats; D004044:Dietary Proteins; D005232:Fatty Acids, Volatile / Q000737:chemistry*; D005524:Food Technology; D005782:Gels; D057927:Hydrophobic and Hydrophilic Interactions; D008956:Models, Chemical; D009812:Odorants; D013816:Thermodynamics; D014835:Volatilization; D014867:Water; D015014:Yogurt
chemical_list: D000085:Acetates; D002087:Butyrates; D002208:Caproates; D004041:Dietary Fats; D004044:Dietary Proteins; D005232:Fatty Acids, Volatile; D005782:Gels; D014867:Water; C007650:ethyl acetate; C079237:ethyl hexanoate; C045572:ethyl butyrate