impacton reducing insectactivity;however, without a goodsanitationpro-
gramme one will nevereliminatethe source of the infestation.
Inspection and monitoring
Directmethods
As mentionedbeforeit is essentialthatlargestock of stored ingredientsand
products, particularlyif theyare not usedor movedat frequent intervals,be
inspectedregularly (withinthe life cycleof the insect)for signsof infestation,so
that control measures can be appliedbeforethe infestationbecomesserious.One of
the mosteffectivewaysof detectinginsectsin raw ingredientsis to installand
inspectsiftingequipment.The firstand mostreliable methodpasses ingredients
overand through the sifterscreen and trailsthe insectsover to reject.The finerthe
ingredientparticlesize,the finer the meshof the siftingscreenmustbe, and the
moreefficientit is in removingall formsof insectlife, including eggs.Stored-
productinsects are most prominent in grains/grain-based food products and
dehydrated fruitsand vegetables. To removeadultstored-product pests, a minimum
30-meshscreenwitha (0.4 mm)meshopeningneeded.The 30-mesh will remove
mostof the insects in the larvastagealso. A 10XXscreen is needed (0.13mm)to
removeeggs.The important detectionmethodis frequently examiningthe tailings
for evidenceof insectinfestation. Thisis veryeffectiveat minimizing large
infestationsthat are brought into the storageand processingsystem.For bulkloads
of productscoming in the sifter,tailingsneedto be inspectedat the beginning,
middle, and end of the unloadingprocess.For in-processinspections, tailingshould
be inspectedonce per shiftfor evidenceof insect infestation.
Anothermeans of detectionis the use of UV lightFlintrol units.The UV
wavelengthemitted fromthese unitsis attractiveto manyflyingstoredproduct
adultinsects and whentheyfly into the unit,the insectsare electrocutedand
theyfall into a collection pan.Weeklyinspectionof the collection panscan
providethe first sign of a problemwithan ingredient or finished product stored
in a warehouse or process area.
Glueboard zonemonitors are similarto rodent glueboards; however, theyare
madeto be attachableto walls, columnsor palletsand are designedto monitor
for insectactivity. Severaltypesof zonemonitors utilizea foodattractantto
increase its effectiveness.
Pheromone traps are specialized monitoring devices that utilize a sex
pheromoneattractant to lure a particularinsectto the trap. Thisdevice is
particularly useful because it can monitor activity overa large areaof the
facility.Caremust be usedwhenutilizingthis trap becauseone doesnot wantto
lure specificinsects into a facility that are alsoindigenous to the areaof the
storage/processing facility. As a result,they must be utilized and monitoredwith
greatvigilance.
Indirect methods
Nearlyall storedproduct insects causean increasein temperature. Therefore,it
is extremely importantto be awareof temperature changes in the grainbulkby
Improvingthe control of insects in foodprocessing 419