- Sampling of raw ingredients and the finished products of aquaculture feed
milling should be conducted routinely so as to be certain that the raw materials
going into the feed and the finished feed itself meet formula specifications
(Bates, Akiyama and Lee, 1995) and do not contain any defects which could
be harmful to the farmer’s crop or the human consumer. For additional
information and details see AFIA (1993), AOAC (1990), Boonyaratpalin &
Chittiwan (1999), Divakaran (1999), Dong & Hardy (2000), Hardy & Roley
(2000), McEllhiney (1994) and Parr (1988).
Ingredients:
- If bulk truck shipments are sampled, samples should be taken from the beginning,
middle and end of the discharge stream. Avoid taking samples from the very
beginning and very end. Grain should be sampled with a grain probe in at least
5 locations (4 corners and middle).
- Railroad box cars, barges and sea containers may be sampled in several
locations during the unloading operation. Avoid taking samples close to the
outside walls.
- If sampling railroad hopper cars (and some barges), each compartment should
be sampled by obtaining 3 samples at appropriate intervals (beginning, middle
and end of loading) during the discharge. Avoid sampling the very beginning
or very end of the discharge.
- Samples of liquid ingredients (i.e., fats, oils, tankage) may be taken
from the unloading stream after the load has been allowed to discharge for
at least 5 minutes.
- If sampling bagged shipments, samples should be taken by diagonal probing.
(The hole made by the probe should be resealed with tape immediately after
sampling.)
- All subsamples should be placed in a large container, mixed, and approximately
1/4 to 1/2 kilogram placed in an appropriate container. All samples should
be identified by date, car (barge, container, etc.) number, ingredient, receiving
report number, supplier, sample name, and name of sampler.
- Ingredients should be periodically tested when or if pesticides or other
toxicants are suspected, and, in some instances, the product should be checked
microscopically. Sampling to determine whether ingredients meet specifications
may be necessary if there is any doubt about the quality of goods received.
- The production manager should determine what tests are appropriate and
should be responsible for evaluating the results.
- All samples of ingredients and finished product must be well-preserved
and protected against destruction (rodents, insects, etc.), deterioration
(moisture, mould, etc.) or adulteration. A preferred means of preservation
is to put the samples in a chest freezer or refrigerator.
Finished Feeds:
- Every production run, bag feed or bulk, should be physically inspected
for: colour, odour, texture, and moisture (when appropriate).
- Samples of bagged production runs should be taken periodically.
- When sampling bulk shipments, appropriately spaced samples should be taken
at intervals (beginning, middle, and end of loading). Taking samples at the
very beginning or end of the loading process should be avoided.
- All subsamples should be placed in a large container, mixed, and approximately
1/4 to 1/2 kilogram placed in an appropriate container. Bagged production
run samples should be identified with a properly coded tag. Bulk or liquid
feed samples should be identified by customer name, date delivered, and quantity
(kilos, etc.).
- The production manager should determine appropriate tests and be responsible
for evaluating the results.
- The above sampling procedure may also apply to liquid feeds, premixes,
supplements, and concentrates. Analytical testing of specific ingredients
for toxicants should follow standard AOAC (1990) methods or equivalent nationally
approved analytical methods.
