Abstract
Hydrophobic prolamins are endosperm storage
proteins accounting for about 40% of the
total protein in most cereal seeds. Despite the
absence of a reference method, several procedures
have been periodically published to
quantify prolamins in cereals. The aim of this
study was to compare a conventional fractionation
assay (LND) vs three other methods: one
based on sequential extractions (HAM) and
two rapid turbidimetric procedures (L&H and
DRO). Prolamins were extracted in duplicate
on barley, corn and wheat samples. For the turbidimetric
prolamin evaluation in barley and
wheat, a universally available purified gliadin,
as alternative to purified zein, was also tested
as standard reference material (SRM). The
extraction prolamin values were different
among grain types (P<0.01) and methods
(P<0.01) without interaction (P>0.05). LND
agreed sufficiently well both with HAM and
with L&H methods (R2=0.664 and R2=0.703,
respectively, P<0.01). On all tested cereals,
LND and L&H gave similar prolamin extraction
values (P>0.05), whereas a higher prolamin
quantification was obtained using HAM
(P<0.05). Overall, DRO did not provide similar
comparison and performance parameters with
respect to other method comparisons. The
effect of changing purified zein with purified
gliadin was noteworthy only for L&H, both for
wheat and barley samples (P<0.01).
Considering the increasing attention of animal
nutritionists on prolamins, our results
could get useful information for routine laboratory
analysis.
Lingua originale | English |
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pagine (da-a) | 7-13 |
Numero di pagine | 7 |
Rivista | Italian Journal of Animal Science |
Stato di pubblicazione | Pubblicato - 2011 |
Keywords
- cereals
- extraction method
- prolamin