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Chapter 2: Analytical Tests of Fats and Oils


Fats and Oils
Pages 15-27
DOI: https://doi.org/10.1094/9780913250907.002
ISBN: 0-913250-90-2






Abstract

Topics Covered

  • Physical Tests
    • Solid Fat Index/Content
    • Melting Point
    • Cloud Point
    • Oxidative Stability
    • Fire Danger Points
    • Polar Lipids in Frying Fat
    • Sensory
    • Plasticity
  • Chemical Tests
    • Fatty Acids
    • Iodine Value
    • Oxidative Degradation
    • Phosphorus (Residual Gums)
    • Unsaponifiable Material
  • Product Specifications

Introduction to Chapter

Analytical tests are important at every stage in the use of fats and oils. Measurements made on crude oil help determine some of the refining parameters, while measurements on fat and oil products ensure that individual refining steps have been carried out correctly. The finished product must match the expectations of the customer for that product. The fat processor's finished product specifications are (or should be) the same as the customer's raw material specification. To make these match, both parties (vendor and buyer) should be using the same tests, performed by qualified analytical personnel.

There are two manuals of standard analytical methods for fats and oils. At least one, if not both, of these must be on the shelf of the quality control laboratory. These are:

  • D. Firestone, ed. Official Methods and Recommended Practices of the American Oil Chemists Society, 4th ed. AOCS, Champaign IL, 1990
  • C. Paquot and A. Hautfenne, eds. IUPAC Standard Methods for the Analysis of Oils, Fats, and Derivatives, 7th ed. Blackwell Scientific Publications, Oxford, London, UK, 1987. A Diffenbacher and W.D. Pocklington, eds., 1st Supplement, Blackwell, 1992

Procedures for performing most of the tests discussed below are given in one or both of these sources. In some instances, no standard method is available, and a pragmatic alternative is suggested. The specific method references for the various tests are given in Table 2-1.