- Feed ingredients which are dry before processing should be kept dry and
cool and used on a first-in, first-out basis. As a general rule the moisture
percentage should be less than 13% particularly in humid and/or tropical areas
(Cruz, 1996; Parr, 1988).
- The tanks in which these ingredients are commonly stored should be cleaned
monthly, or as indicated by experience, to prevent the build-up of dust and
fragments of feedstuffs. Such build-up creates habitat for mould (and therefore
the possible production of mycotoxins) and insects which will quickly destroy
the food value of the products being stored; heat is also produced by these
organisms and spontaneous combustion resulting in serious ingredient losses,
and possible property losses may occur. The elevator legs, other conveying
equipment and spouting should also be routinely inspected and cleaned out
for the same reasons.
- While processing may dilute or kill concentrations of mould and insects,
keeping equipment and storage free of dust and build-up of old feedstuffs
will prevent or at least reduce the possibility of contamination of the finished
feed.
- Liquid ingredients such as tallow, amino acids, and molasses should be
stored in accordance with manufacturers’ recommended procedures to protect
freshness.
- Fats and oils may need to be heated for ease of handling and/or have antioxidants
added (to prevent lipid peroxidation and control off-flavors in food animals)
to maintain quality (Hardy & Roley, 2000).
- In general, aquafeeds are usually composed of some highly perishable and
often very expensive ingredients and care must be taken to keep both the feed
ingredients and the finished feed away from contamination including heat and
light, as well as biological factors such as mildew, insects, birds and rodents
(Cruz, 1996; O’Keefe, 2000).
- Propionic acid and other antifungal agents may be used during processing,
but these chemicals may adversely affect palatability and efficacy of the
feed. Both the feed miller and the farmer/end user of the feed need to remember
that heat, light, and moisture can damage feed and that sacked feed should
be stored off the ground on pallets, and out of direct sunlight due to the
damaging effects of ultraviolet rays (New, Tacon and Csavas, 1995).
- Depending upon the source and nature of bulk feedstuffs, ingredient cleaning
may be necessary. Most feed mills have grain cleaning systems, designed to
remove broken seed, tramp metal, and other foreign materials which contaminate
inbound ingredients from time to time.
- It is wise for the buyer to specify that dust (fines) and other contaminants
shall not exceed a certain level. Inbound ingredients should be subject to
rejection if contamination levels exceed specification.
- Aquatic animals are particularly sensitive to low levels of, for example,
fumigants, and possibly mycotoxins, and for that reason great care must be
taken in the choice, sourcing and handling of feed ingredients for aquaculture
(Cruz, 1996).
- Bins, silos, warehouses, and ingredient handling systems should be designed
so that moisture, rodents, birds and other pests are denied access. Regular
cleaning of storage facilities will go a long way toward assuring a high quality
finished product.
- One of the main components of receiving and storing is proper scheduling
of the arrival of ingredients so as to minimize storage time and handling
of the ingredients. Quality of ingredients, be they sacked supplements and/or
medications, or bulk corn, or soybean meal, for example, may lose nutrient
value or efficacy from excessive handling. Handling also invites problems
with shrink.
- Misformulated, damaged or returned feed must be stored such that it cannot
contaminate other feeding stuffs. Confirming analysis should be made to determine
if such waste feed can be reprocessed, or must be destroyed. Here again a
paper trail is important, especially for medicated feeds.
