No abstract

Volatility of two aroma compoundssethyl butanoate and ethyl hexanoateswas investigated in monophasic and biphasic systems. Monophasic systems were either water, an aqueous solution of sodium caseinate or sucrose stearate, or triolein. Biphasic systems, emulsified or not, consisted of triolein and one of those aqueous phases. Volatility measurements were carried out by headspace analysis and exponential dilution. In homogeneous systems, aroma retention was affected by the nature of the nonvolatile compounds: it was nearly 100% in triolein for both ethyl butanoate and ethyl hexanoate; in 5 g/L aqueous solution of sodium caseinate or sucrose stearate, retention values were 20% and 35% for ethyl butanoate and ethyl hexanoate, respectively. In biphasic systems, the vapor-liquid partition coefficient of ethyl hexanoate was not changed whether or not the system was emulsified and regardless of the nature of the surface active compound, i.e., sodium caseinate or sucrose stearate.

No abstract

Relative retention, volatility, and temporal release of volatile compounds taken from aldehyde, ester, and alcohol chemical classes were studied at 70 degrees C in model systems using equilibrium static headspace analysis and real time dynamic headspace analysis. These systems were medium-chain triglycerides (MCT), sunflower oil, and two structured systems, i.e., water-in-oil emulsion and L2 phase (water-in-oil microemulsion). Hydrophilic domains of the emulsion type media retained specifically the hydrophilic compounds and alcohols. Four kinetic parameters characterizing the concentration- and time-dependent releases were extracted from the aroma release curves. Most of the kinetic parameter values were higher in structured systems than in oils particularly when using MCT. The oil nature was found to better control the dynamic release profiles than the system structures. The release parameters were well-related (i) to the volatile hydrophobicity as a function of the oil used and (ii) to the retention data in the specific case of the L2 phase due to a specific release behavior of alcohols.