Solid-state emulsions: evaluation by 1H and 13C solid-state nuclear magnetic resonance

The molecular environment of sucrose and mineral oil within sucrose and mineral oil solid state emulsions was investigated by NMR techniques. The 13C and 1H chemical shifts of sucrose and mineral oil to those observed in solid state emulsions (comprised of sucrose and mineral oil) were equivalent, indicating that the local structure of sucrose is unaffected by the presence of mineral oil in the solid-state emulsion. Cross-polarization, magic angle spinning 13C (CP-MAS) in conjunction with single-pulse studies indicated that the 1H-13C dipole-dipole interactions are very weak, i.e., mineral oil is highly mobile. Spinning side bands were observed, however, in 1H single-pulse, magic angle spinning (SPMAS) spectra of the solid-state emulsion, indicating that the mineral oil has solid properties. Although the mineral oil was shown to be highly mobile, it also appears to be constrained or included by the sucrose.