Tsachaki Maroussa, Gady Anne-Laure, Kalopesas Michalis, Linforth Robert S T, Athès Violaine, Marin Michele, Taylor Andrew J
Samworth Flavor Laboratory, Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, United Kingdom.
J Agric Food Chem. 2008 Jul 9;56(13):5308-15. doi: 10.1021/jf800225y. Epub 2008 Jun 5.
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.
基于一个机理模型，当惰性气体稀释简单乙醇/水溶液（乙醇浓度 = 120 mL×L⁻¹）上方的静态顶空时，估算了香气化合物在香气释放过程中的总传质系数和液相传质系数。对17种化合物进行了研究，与水溶液相比，它们在乙醇/水溶液中的传质系数均有所增加，表明由于乙醇的存在，除了分配系数变化外，传质效果更好。热成像结果显示了两种体系（水和乙醇/水）对流的差异，这表明液体内部乙醇对流增强。溶液中乙醇对不同温度下传质系数的影响较小。相反，在不同的顶空稀释率下，当顶空每分钟补充1 - 3次时，溶液中乙醇的作用有助于使挥发性顶空浓度保持接近平衡浓度。
