U2

carboxylic acids with a short to long aliphatic chain

organic compounds where carbon atoms form open chains rather than rings

melting point decreases as number of double bonds increases

unbranched varying length and degree of saturation 4-28C even numbered usually usually cis

• more volatile • lower melting point • liquid at RT • more soluble in water

• not volatile - dont contribute to flavor • higher melting point • solid at RT • less water soluble - more hydrophobic

pentadecanoic acid and heptadecanoic acid

the salt form of a fatty acid water soluble and has strong surface tension reducing properties

trivial and IUPAC

IUPAC and trivial and omega • -enoic acid • positional reference • configuration

IUPAC - count from COOH omega - count from CH3

• kinked, not linear • 1 bond = 40 degree turn • harder to form a lattice structure so… • lower melting point • lower density

• linear • metabolized like saturated fatty acids • higher melting point • higher density

elaidic acid - a lot like stearic acid

double bonds are separated by a methylene group (CH2) - normal

double bonds are adjecent. formed during processing. more thermodynamically stable but more susceptible to autoxidation

mixture of conjugated and unconjugated. occurs since linolenic and polyunsaturated fatty acids are unstable and reactive, thus easily converted to having both conjugated and unconjugated elements

stabilized by hydrophobic interaction along acyl residues. temperature required to melt the crystal increases with number of carbons in the chain (length)

can - saturated, even, trans can’t - unsaturated, odd

the angle the fatty acid is bent at is lower, thus the molecule is more linear and the melting point is higher

• cis 2. unconjugated

due to the relationship between unsaturated, unconjugated fatty acids there are 3 groups: • w3 • w6 • w9

branced fatty acid found in cottonseed oil contains a cyclopropanic ring (triangle)

hydroxy side chain. in castor oil