福州大学：《食品化学》课程教学课件（PPT讲稿）Cocoa Butter

Cocoa Butter crystallization,tempering,bloom

Cocoa Butter crystallization, tempering, bloom

Plan Lipid structure,crystallization polymorphism Tempering theory practice ·Bloom

Plan • Lipid structure, crystallization & polymorphism • Tempering theory & practice • Bloom

Fatty Acids Stearic acid 18 carbon carboxylic acid linear molecule Oleic Acid 16 carbon carboxylic acid single double bond puts a "kink" HO

Fatty Acids Stearic acid 18 carbon carboxylic acid linear molecule Oleic Acid 16 carbon carboxylic acid single double bond puts a “kink” C O HO

Fatty Acids in Cocoa Butter 26wt% 16:0 Palmitic acid 34wt% 18:0 Stearic acid 35wt% 18:1 Oleic acid .plus about 5 others

Fatty Acids in Cocoa Butter .plus about 5 others 26 wt% 16:0 Palmitic acid 34 wt% 18:0 Stearic acid 35 wt% 18:1 Oleic acid

0 -CH2 CH CH Triglycerides take on a tuning fork configuration

Triglycerides take on a tuning fork configuration

Homogeneous Nucleation T=Tmelt T<<Tmelt supercooling True melt Crystal embryos Crystal lattice

True melt Crystal embryos Crystal lattice T>Tmelt T=Tmelt T<<Tmelt supercooling Homogeneous Nucleation

Heterogeneous Nucleation T-I melt T<Tmelt less supercooling True melt Nucleation Crystal lattice

True melt Nucleation Crystal lattice T>Tmelt T=Tmelt T<Tmelt less supercooling Heterogeneous Nucleation

SFC is a function of temperature SFC is a function of 100%solid temperature history SFC is a function of time SFC is a function of composition heating cooling 100%liquid cold hot Temperature

Temperature cold hot 100% liquid 100% solid Solid Fat Content • SFC is a function of temperature • SFC is a function of temperature history • SFC is a function of time • SFC is a function of composition

Polymorphism Molecular packing can vary by angle of tilt

Molecular packing can vary by angle of tilt. Polymorphism

.and by chain packing

.and by chain packing