Sphingolipids z Sphingomyelin, a ceramide with a phosphocholine or phosphethanolamine head group, is a common constituent of plasma membranes z A cerebroside is a sphingolipid (ceramide) with a monosaccharide such as glucose or galactose as polar head group. H2C H C O CH NH CH C CH2 CH3 H OH ( )12 C R O O O P O H2 C H2 N C + CH3 H3C CH3 Sphingomyelin phosphocholine sphingosine fatty acid − cerebroside with β-galactose head group H2C H C CH NH CH C CH2 CH3 OH C R O OH O H H H H OH OH CH2OH H O H ( )12
Sphingolipids z Sphingomyelin, a ceramide with a phosphocholine or phosphethanolamine head group, is a common constituent of plasma membranes z A cerebroside is a sphingolipid (ceramide) with a monosaccharide such as glucose or galactose as polar head group. H2C H C O CH NH CH C CH2 CH3 H OH ( )12 C R O O O P O H2 C H2 N C + CH3 H3C CH3 Sphingomyelin phosphocholine sphingosine fatty acid − cerebroside with β-galactose head group H2C H C CH NH CH C CH2 CH3 OH C R O OH O H H H H OH OH CH2OH H O H ( )12
Attributes of Food Lipids z Three major functions in foods – Energy and health – Influence food flavors z free fatty acids contribute flavors z lipids act as solvents for carrying hydrophobic flavors and aromas (and nutrients) – Texture z Solid vs liquid z Emulsions Attributes determined by types and positions of fatty acids on glycerol backbone
Attributes of Food Lipids z Three major functions in foods – Energy and health – Influence food flavors z free fatty acids contribute flavors z lipids act as solvents for carrying hydrophobic flavors and aromas (and nutrients) – Texture z Solid vs liquid z Emulsions Attributes determined by types and positions of fatty acids on glycerol backbone
Plant Triglycerides z Cocoa butter –~ equal 16:0, 18:0, 18:1 – sn-2 primarily unsat’d (U) – sn-1,3 mostly sat’d (S) 0 10 20 30 40 50 60 70 80 90 mole % of fatty acid groups C16:0 C18:0 C18:1 C18:2 fatty acid constituent sn-1 sn-2 sn-3 all – Coconut, palm oil richer in 8:0-16:0 (Belitz and Grosch, 1999; © Springer-Verlag.) S S U 81% U S U 15% (S at sn-1 or sn-3)
Plant Triglycerides z Cocoa butter –~ equal 16:0, 18:0, 18:1 – sn-2 primarily unsat’d (U) – sn-1,3 mostly sat’d (S) 0 10 20 30 40 50 60 70 80 90 mole % of fatty acid groups C16:0 C18:0 C18:1 C18:2 fatty acid constituent sn-1 sn-2 sn-3 all – Coconut, palm oil richer in 8:0-16:0 (Belitz and Grosch, 1999; © Springer-Verlag.) S S U 81% U S U 15% (S at sn-1 or sn-3)
z Coconut oil – 80% of triacylglycerols are trisaturated z Lauric at sn-2 z Octanoic at sn-3 z Myristic or palmitic at sn-1 Plant Triglycerides
z Coconut oil – 80% of triacylglycerols are trisaturated z Lauric at sn-2 z Octanoic at sn-3 z Myristic or palmitic at sn-1 Plant Triglycerides
Plant Triglyceride s z Peanut Oil – ~40% oleic; 40%linoleic – sn-2 largely unsat’d – Soybean oil similar 0 10 20 30 40 50 60 mole % of fatty acid groups C16:0 C18:0 C18:1 C18:2 fatty acid constituent sn-1 sn-2 sn-3 all (Belitz and Grosch, 1999; © Springer-Verlag.) S U U U U U (< 30%) (> 70%)
Plant Triglyceride s z Peanut Oil – ~40% oleic; 40%linoleic – sn-2 largely unsat’d – Soybean oil similar 0 10 20 30 40 50 60 mole % of fatty acid groups C16:0 C18:0 C18:1 C18:2 fatty acid constituent sn-1 sn-2 sn-3 all (Belitz and Grosch, 1999; © Springer-Verlag.) S U U U U U (< 30%) (> 70%)