Sachiko Odake

Flavor release of diacetyl and 2-heptanone from cream style dressings in three mouth model systems.

The release of volatile compounds from a cream style dressing, which consisted of a thickening agent dispersed in the water phase of an oil in water (o/w) type of emulsion, was studied by the purge-and-trap (PT), dynamic head space mastication (DHM) and dynamic headspace (DH) model systems for diacetyl and 2-heptanone as two volatile compounds. Big differences were detected in the quantity of volatiles released by the three models for both diacetyl and 2-heptanone: PT released the most, followed by DHM and DH. Nitrogen gas bubbling in PT and plunger up-and-down motion in DHM mimic mouth movements and promoted volatile release more than DH. The quantity of volatiles released depended on the nitrogen gas flow rate and isolation period with both the PT and the DHM model. Static headspace measurements indicated that no interaction occurred between the volatiles and the dispersion thickening agent, nor between the volatiles and protein of saliva.

The Diffusion of Seasoning Substances in Various Slurries -Application of Nondestructive Measurement Using Ultrasonic Technique-

An apparatus which applies the ultrasonic technique was constructed to measure the diffusion coefficients of sodium chloride in corn starch sols. At a frequency of 1 MHz, the ultrasonic velocity was observed to increase proportionally with the concentration of sodium chloride and of starch. By employing the ultrasonic technique, it becomes possible to detect the concentration changes continuously and nondestructively. Furthermore, the accurate diffusion coefficient of substances in fluids may be obtained. The diffusion coefficients of sodium chloride in 1%, 3% and 5% corn starch sols were obtained as 1.12, 1.07 and 0.94 x 10-5 cm2/s, respectively.