Study of the State of Water and Oil in Frozen Emulsions Using Time Domain NMR

• Published in: Journal of colloid and interface science 2000-06, Vol.226 (1), p.16-21
• Main Authors: Le Botlan, D., Wennington, J., Cheftel, J.C.
• Format: Article
• Language: English
• Subjects: frozen emulsion; T1 and T2 relaxation time; time domain NMR
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1006/jcis.2000.6785

Here T1 and T2* relaxation time measurements by low-field NMR have been used to quantify the state of oil and water in frozen emulsions. Water-in-oil and oil-in-water emulsions have been studied. A discrete method (NLREG program) and a continuous method (CONTIN program) have been used to analyze the FID and inversion-recovery relaxation curves. The FID signal (T2*) analysis allowed us to calculate the global solid–intermediate–liquid ratio, and the state of the solid and liquid phases was determined by the T1 values. Thus we have been able to show that the major part of water (∼99%) is in a solid state in such emulsions (average droplet diameter of about 1.5 μm). This result was confirmed by the study of a solid paraffin–Span 80–water emulsion and a heavy water–caseinate–triolein emulsion. These first results have shown the interest of this new method for the study of the state of water and oil in frozen emulsions.