ied GC and/or Analyst contributions on the quality of MLT Data
Absence (or limited) problems for the quantification of: C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C14:1 n-5, C16:0, C18:0, C18:2 cis n-6, C18:3
n-3 (a), C20:0, C20:3 n-6 (dhgla), C20:3 n-3, C20:5 n-3, C22:0, C22:1 n-9, C22:2 n-6, C22:6 n-3, C24:0, and C24:1 n-9
Comment
Fatty Acid
One peak but co-elution is possible (branched fatty acids in dairy)
C15:0, C15:1 n-5,
C16:1 n-7, C17:0
Possible presence of two isomers (n-7 or n-8) and possible co-elution (branched fatty acids in dairy)
C17:1 n-
One peak but possible wrong identification or co-elution C18:3 trans isomers
C18:3 n-6 (g)
One peak but presence of other C20:1 isomers (
i.e.
dairy) and/or co-elution with C18:3 trans isomers
C20:1 n-9
One peak but possible co-elution with C20:2 n-6 (
i.e.
dairy)
C-18:2 CLA
One peak but possible co-elution with CLA isomers (
i.e.
dairy)
C20:2 n-6
One peak but possible co-elution or wrong peak identification (e.g. C22:1 n-9)
C20:4 n-6 ARA
Always two peaks (n-9 & n-7) the n-7 cis isomers is naturally present in fats & oils. MUFA and w-9 results can be
impacted with error in reporting for C18:1 cis
C18:1 cis
Presence from Δ4 to Δ16
trans
isomers (i.e. dairy fat), traces of hydrogenated fat in vegetable oils
C18:1
trans
Various isomers having different origin (i.e.
trans
in deodorized vegetable oil)
C18:2
trans
Absence in milk, but presence of 2,3 or 4
trans
isomers in deodorized vegetable oil and/or possible co-elution with
C18:3 n-6 g and C20:1 isomers
C18:3
trans
Sum of C18:1, C18:2 & C18:3
trans
The final result can be impacted by individual results reported separately for C18:1
trans
, C18:2
trans
and C18:3
trans.
TFA
