Effect of ethanol, temperature, and gas flow rate on volatile release from aqueous solutions under dynamic headspace dilution conditions.
On the basis of a mechanistic model, the overall and liquid mass transfer coefficients of aroma compounds were estimated during aroma release when an inert gas diluted the static headspace over simple ethanol/water solutions (ethanol concentration = 120 mL x L(-1)). Studied for a range of 17 compounds, they were both increased in the ethanol/water solution compared to the water solution, showing a better mass transfer due to the presence of ethanol, additively to partition coefficient variation. Thermal imaging results showed differences in convection of the two systems (water and ethanol/water) arguing for ethanol convection enhancement inside the liquid. The effect of ethanol in the solution on mass transfer coefficients at different temperatures was minor. On the contrary, at different headspace dilution rates, the effect of ethanol in the solution helped to maintain the volatile headspace concentration close to equilibrium concentration, when the headspace was replenished 1-3 times per minute.
Samworth Flavor Laboratory, Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, United Kingdom. maroussat@gmail.com
Maroussa
M
Tsachaki
Anne-Laure
AL
Gady
Michalis
M
Kalopesas
Robert S T
RS
Linforth
Violaine
V
Athès
Michele
M
Marin
Andrew J
AJ
Taylor
D000431:Ethanol / Q000737:chemistry*; D007700:Kinetics; D013058:Mass Spectrometry; D008956:Models, Chemical; D044367:Phase Transition; D012996:Solutions / Q000737:chemistry*; D013696:Temperature; D014835:Volatilization
D012996:Solutions; D000431:Ethanol