Small angle neutron scattering from voids in crystalline trilaurin

  • D. J. Cebula
  • D. J. McClements
  • M. J. W. Povey
Article

Abstract

Small Angle Neutron Scattering (SANS) experiments show that a high density of voids of molecular size is formed within the crystalline structure of solidified trilaurin. It is proposed that these voids are defects in the crystal structure and that ordinary metallurgical concepts of defect controlled crystal growth and material strength may be applied to trilaurin and, by analogy, other triglycerides. The presence of voids would explain the anomalous expansion of simple, saturated triglycerides on cooling. SANS experiments did not reveal evidence of liquid crystalline order in trilaurin, supercooled below its β melting point. If ordered regions do exist, their density contrast with the disordered liquid must be less than 1% (the sensitivity of the instrument) or their scale must lie outside the region between 9.3 and 63 nm.

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Copyright information

© AOCS Press 1990

Authors and Affiliations

  • D. J. Cebula
    • 1
  • D. J. McClements
    • 2
  • M. J. W. Povey
    • 2
  1. 1.Unilever Central Research LaboratoriesColworth HouseShambrookUK
  2. 2.Department of Food ScienceUniversity of LeedsWest yorkshireUK

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