314 / 328
ER 5
Satisfactory
ER 6
Method is clearly written I didn't have problems following it, with the exception of the units used for
the enzyme activities. It would be preferable for the authors to define the units of activity for each
enzyme since definitions vary from manufacturer to manufacturer. This will be fundamental if the
enzymes used need to be replaced with others.
ER 7
good
ER 8
Well thought through study and well written
Pros/Strengths
ER 1 Single vessel
ER 2
Relatively more efficient method. Very well studied and validated in SLV. 15 labs. collaboratively
studied the method and analyzed 10 homogenous test materials (animal feeds and pet foods) using the
described method for dietary starch (ranging starch contents of 1-70%). The average within lab.
Repeatability as sr for % Dietary starch was 0.49 with a range of 0.03 to 1.56, and among –laboratory
repeatability of standard deviation sR averaged 0.96 with a range of 0.09 to 2.69. HORRAT averaged 2.0
for all test samples and 1.9 for samples containing dietary starch more than 2%.
ER 3
Measurement of carbohydrates by enzyme-digestion and analysis of the liberated mono-saccharides is
an established approach which has worked well for a range of carbohydrates. The collaborative data
from this study demonstrates this approach works well for dietary starches due to properly accounting
for sucrose & inherent glucose interferences, and in deterring formation of maltulose. Dietary starch is
digested to glucose and the increase in glucose level is used to calculate %dietary starch. Potential
interferences are either accounted for (inherent glucose) or excluded (deter inherent sucrose digestion
and deter maltulose formation).
ER 4
Traditional chemistry that has been well studied. Can be carried out in modestly equipped laboratories
by technical personnel with modest training.
ER 5
Relatively straightforward procedures Satisfactory recovery on glucose and corn starch. Low
interference from sucrose , β-glucan and cellulose. Good repeatability and reproducibility.
ER 6
- A simple method that does not need specialized equipment. - option to use alternative methods for
glucose analysis is mentioned if a lab does not wish to use the GOPOD assay
ER 7
no comment
ER 8
The specific advantages of this method over AOAC Method 996.11 are not clear. With both methods,
good
reproducibility and recovery of starch was obtained over a wide range of samples. This method is no
easier to
perform than 996.11.
Cons/Weaknesses
ER 1 None
ER 2
The method underestimates dietary starch in feeds and foods whose antioxidant content is known to
exceed 10-20 micromol of hydrophilic antioxidant (as ascorbic acid) per 0.1 g of test dry matter. The
method in the current format may not be easily applicable to foods/feeds high in phenolic compounds
(e.g. beets, red sorghum grain).
ERP PROFILE SUMMARIES
274