Contribution of Particle Sizes and Particle Size Distributions in Crystalline Fractionation of Lard

Abstract

Particle sizes and particle size distributions of lard in the process of multiple-step crystalline fractionation were studied by natural sedimentation spectrophotometry according to Stokes's law and Beers's law. The average particle size diameter and their distributions of lard fractions varied with the crystallization temperatures. Average particle size decreased significantly 0, < 0.05) with the crystallization vessel cooling rates (0.5, 1.0, and 2.0 "C min-l) and agitator speeds (50,100, and 150 rpm). Furthermore, the firmness of lard crystal fractions decreased with the vessel cooling rate and agitator speed. Decreases in average particle sizes in addition to the firmness of lard crystal fractions were related to the increase in unsaturated fatty acid and to their triglyceride compositions.

Suitable cooling program for chicken fat dry fractionation

“…2d). Wang and Lin [5] also demonstrated that the mean size of crystals (as measured by spectrophotometry) decreases as the cooling rate increases. Herrera and Hartel [4] drew the same conclusions in a study on milk fat using polarized light microscopy.…”

“…They have an impact on the nucleation rate [2], crystal number and size [3][4][5], crystalline polymorphism [6] and the nature of the crystallized triacylglycerols. During dry fractionation of these fats, cooling conditions affect the quality of the resulting fractions [7][8][9].…”

Characterisation of chicken fat dry fractionation at the pilot scale

“…The cooling rate, and more directly the degree of supercooling, have a major impact on crystal morphology (number and size) (Wang and Lin [29]), fraction yield and quality (Deffense [5]; Deffense [30]). A higher degree of supercooling leads to the formation of a large number of nuclei and uncontrollable crystallisation, i.e.…”

Composition and Thermal Analysis of Lard Stearin and Lard Olein

“…Firmness of lard was improved through blending with hydrogenated stock 2 or hard component isolated from fractional crystallization. In the past, the separation of hard component of lard stearin has been accomplished through techniques such as short-path distillation 8 , supercritical carbon dioxide extraction 9 , or dry and solvent crystallization 10,11 . Although stearin is the mainly targeted product, a fair proportion of the liquid component is also recovered as the co-product of fractionation.…”