6
Stakeholder Comments
3.
I would replace the phrase “free and/or total” with “total individual” in the applicability
statement From a nutritional perspective it is the total amount of the individual amino acids
.
that is important, not the fact that they are free or protein bound.
We do not disagree with this
reasoning but feel that, although the total content is generally the nutritionally relevant measure,
the distinction is necessary in order obtain methodology with the flexibility to determine only
free forms, if only because of the procedural simplification that this allows in those cases
(although limited) where only free amino acids are relevant. An example would be Elemental
formulas manufactured with only free amino acids. Free amino acids are added to some
“standard” formulas, as well, and it can be of interest to differentiate free and bound forms.
Stakeholder Comments
4.
The applicability statement lists the amino acids that any method(s) will need to be able to
analyse in Table 1 However I believe that some statement is required that draws the attention of
.
,
potential study authors to the fact that any submitted method(s) will need to be able to
distinguish between the unmodified amino acids and amino acids that have been modified as a
result of processing. At the last meeting in March, I made this comment and the reply to that
comment was that this point should not be part of the SMPR, but rather, was an issue that would
be addressed when the submitted methods are evaluated by the ERP. However, I don’t agree and
I can envision a situation where many submitted methods will have to be rejected by the ERP
simply because potential study authors were not aware of the effects of food processing on
amino acids. The classic example would be where methods for determining methionine and
cysteine that are based on performic acid oxidation. The latter methods are unsuitable if
methionine and/or cysteine have been partially oxidised in the infant formulas as a result of their
processing during manufacture. Consequently, I would recommend adding text to the legend of
Table 1 to mitigate that possibility. For example: “where applicable, methods must be able to
distinguish between the “native” amino acid and any amino acid derivative that that is present as
a result of the processing during manufacture (eg. lysine that has undergone Maillard reactions or
oxidised methionine and cysteine)”.
