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ER 4
See method scope and applicability statement.
ER 5
Applicable to pet foods (wet and dry), animal feed, forage, as well as grains.
ER 6
method has been applied to a range of different animal feeds; canned dog food, low starch horse feed,
ground corn, complete dairy feed, soybean meal, distillers grains, poultry feed, corn silage, dry dog
kibble, alfaalfa pellets. It is applicable for the analysis of "dietary starch" as defined in the introduction
of the paper.
ER 7
good
ER 8
Non-resistant starch in animal feeds
General Comments
ER 1 Positive feedback from collaborators
ER 2
The manuscript describes a method and SLV and its performance in multilaboratory study for dietary
Starch (glycogen, maltooligosaccharides, and other alpha-1,6-linked glucose carbohydrates, exclusive
of resistant starch). This method is replacement of invalidated AOAC 920.14 due to unavailability of
one of the enzyme required in the assay. The described method is more efficient than other methods
considered.
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.
ER 4
Excellent approach
ER 5
This method is similar to older, but now obsolete methods in principal, with better description in
choice of enzymes and analysis approach of the glucose contents. This method also simplifies
experimental procedures by adding reagents into the same tube until the final dilution step.
ER 6
The principles of the method are good. Enzymes are used to specifically hydrolyse the relevant alpha-
glucans in feeds (i.e. starch, maltooligosaccharides, etc) composed of alpha-1,4 and alpha-1,6 linked
glucose. Other poly- or oligosaccharides should not be hydrolysed. Resulting glucose is determined
using a well established procedure (GOPOD) and free glucose which would interfere is accounted for by
running a sample without enzymatic hydrolysis. I don't know if the concept of resistant starch is used in
the animal feed world. If yes, it would be good to clarify if the methodology is expected to account for
all the starch or only the available starch.
ER 7
none
ER 8
Page 2, line 25. In reference to AOAC Method 996.11, the author refers to the method being “quasi-
empirical” and justifies this by stating that “glucose is the analyte detected, but its release is
determined by run conditions and specification of enzymes.”
The term “quasi-empirical” is unacceptable. This method was run through a full AOAC International
interlaboratory evaluation involving 31 laboratories and over this number, the RSDr and RSDR values
were similar to those reported in this paper. In reference to the comments about the run conditions
and specification of enzymes, of course the method was defined. This is a requirement of any method.
It is especially important to specify details of enzymes and particularly purity. This is the reason why so
many enzyme based methods have failed in the past. It is dangerous to recommend industrial, or in
fact any, enzymes that have not been analysed for activity and purity (contamination with other
ERP PROFILE SUMMARIES
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