Ultrasound assisted water extraction from spice and determination on-line by using continuous manifold flow and Karl-Fisher reagent

ANYL 75

María del Pilar Cañizares-Macías, pilarm@servidor.unam.mx and Thania Susana Jiménez-Martínez. Department of Analytical Chemistry, Autonomous National University of Mexico, Ciudad Univeristaria, Mexico D.F, 04510, Mexico
Ultrasound assistance is increasingly being used in analytical chemistry, enabling different steps in the analytical process, particularly in sample preparation. In this study by means of a 3 mm probe, ultrasound waves were applied to a methanol solution containing Mexican spices such as vanilla, parsley, coriander, epazote herb, avocado leaf, bay leaf, damiana, pingüica, jamaica flower and spearmint. The extracted water was measured online using a continuous manifold flow and Karl-Fisher reagent. The environmental water was eliminated before the extraction using a flow of N2. Excellent results were obtained, with an extraction time of 2 min. for spices containing less of 15 % of water, and of 6 min. for samples with 15 % or more, whereas with the standard method, (by using methanol as extractant) it is necessary an extraction time of between 30 min. (if stirring) and 60 min. (when left to stand).
 

General Papers
7:00 PM-9:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

Division of Analytical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006