Introduction - Kansas State Universityspiru.cgahr.ksu.edu/proj/iwcspp/pdf2/9/6151.pdf · P. Trematerra1,*, L ... Plant and Environmental Science, University of Molise, Via De Sanctis,

Alternative Methods to Chemical Control

747

PS7-11 – 6151

Integrated Pest Management in Italian pasta factories

P. Trematerra1,*, L. Süss2

1 Department of Animal, Plant and Environmental Science, University of Molise, Via De Sanctis, I-86100 Campobasso,Italy; e-mail: [email protected]; fax: +39 874404855.

2 Institute of Agricultural Entomology, University of Milan, Via Celoria 2, I-20133 Milano, Italy.* Corresponding Author

Abstract

Pasta factories can be infested by insects,leading to negative economic and commercialconsequences. Considering the importance ofItaly as a producer and exporter, alimentary pastehas been the subject of much research. Pastafactories use semolina, a raw material obtainedfrom hard wheat which comes directly from themill. Because of the structure of the building,the possible use of infested cereals and largequantity of dust always present, semolina is themain source of reproduction and diffusion ofpests. As a result, the same pests [Ephestiakuehniella Z., Plodia interpunctella (Hb.),Lasioderma serricorne (F.), Oryzaephilus spp.,Rhyzopertha dominica (F.), Sitophilus spp.,Stegobium paniceum (L.), Tribolium spp.]present in warehouses, silos and in mills arecarried into pasta factories where they canmultiply. In some Italian pasta factories recently,new technics and Integrated Pest Management(IPM) have been suggested for the preventionand control of pests. The results obtained led toextending these methods to improve healthysanitation practices and reduce chemicaltreatments. Despite these provisions, the problemof pest attacks by Lasioderma, Plodia,Rhyzopertha, Sitophilus and Stegobium in pastafactories, from packaging to the consumer,remains unsolved because of specific aspects ofused packaging and the negligence of warehousesand stores in addition to the long average shelf-life of the product. Warehouse managers and

shopkeepers must be involved in the processingcycle by encouraging frequent visits on the partof inspectors and the distribution of bookletsconcerning relevant problems and their possiblesolutions. In the meantime, potential newpackaging methods that are less susceptible topest attacks must be studied. Only by controllingthe entire processing chain will it be possible toreduce the risk of infestation.

Key words: IPM, pasta factories, Italy.

Introduction

Many sources indicate that pasta originatedin China and that the explorer Marco Polo wasthe first to report its existence. In Italy, thewidespread use of handmade and industrialpastas undoubtedly began in Naples in the early18th century, when production of pasta changedfrom manual to mechanical. The use and mix ofbest quality durum wheat, Triticum durum Desf.,combined with unrelenting technologicalresearch have in time decreed the global successof pasta and Italian pasta manufacturers.Production and consumption have received aboost from the technological advancement ofmachines designed to increase productivity andreduce costs.

Italy is at the top of the world league table forthe production and consumption of pasta.According to data gathered by the UnioneIndustriale Pastai Italiani (UNIPI, 2005), global

9th International Working Conference on Stored Product Protection

748

pasta production reached 3,374 million Euro in2004. In terms of quantity, 3,121,598 tons wereproduced, 3,023,589 tons of which consisted ofdried pasta and 98,000 tons of industrial freshpasta. As for domestic consumption (1,591,548tons), annual pro capita consumption was 28 kg,consisting mostly of dried pasta (26 kg), whereasthe consumption of fresh pasta (2 kg) graduallyincreased. Exports (1,530,050 tons) accountedfor 49 % of production and there have been signsof slight growth. In 2004, 63 % of exports weredestined for the 15 member EU countries whereGermany is the principal market. As far as nonEUmarkets are concerned, there were goodperformances in Japan, Russia and the newmarkets of China and India.

From 2000 to 2004, expenditure on pasta rosefrom 23 % to 24 %; in the same period thevolume of pasta sold through modern distributionchannels climbed from 74 % to 78 %. Italianindustry continues to maintain its position asworld leader thanks to its structure, which breaksdown into 152 industrial plants; 121 of theseplants are specialized in the production of driedpasta, 18 in the production of fresh industrial pastaand 13 in the production of both. The productivecapacity of the sector is estimated to be about4,600,000 tons/year, with a degree of plantexploitation of approximately 68 %.

The packaging of dried pasta for familyconsumption involves to two large packagingcategories: solid board boxes and plastic bags(with a structured base and flowpack). For pastaproducts destined for hotel use, restaurants andcatering, large volume paper or plastic bags areused. In contrast, fresh pasta is packaged inprotective plastic (tubs or bags), with the exceptionof fresh pasta with a very short shelflife, whichis packaged using plastic that provides nobarriers, such as tubs wrapped in flexible plasticfilm. Every type of pasta is shipped in corrugatedcardboard boxes transported on pallets.

In the dried pasta sector, production is dividedinto the following percentages: dried semolinapasta, 90 %; dried egg pasta, 6 %; dried stuffedpasta, 4 %.

Pasta destined for the Italian or overseas

consumer is essentially delivered in sealedpackages according to three different quantities(250 gr, 500 gr and 1000 gr) and in two packagingtypologies: cardboard boxes and flexible plasticwrappers. Depending on the various pastafamilies and different markets, the product isdestined for domestic or overseas use anddelivered in specific quantities; packagingtypologies may vary somewhat.

With reference to the three principal categoriesof dried pasta, the choice of packaging differs.When destined for families, 50 % of driedsemolina pasta is packaged in plastic flowpacks,5 % in plastic bags with a structured base and45 % in cardboard boxes. Sixty percent ofproducts destined for hotels, restaurants andcatering are packaged in plastic bags (averagevolume, 10 kg) and 40 % in paper bagscontaining the same volume. The mix remainsessentially the same. Three packaging typologiesare used for dried egg pasta: flowpack pluscardboard tub (85 %); cardboard box (10 %);plastic bag (mainly for small pasta used in broth)5 %. Regarding dried stuffed pasta, whosedemand is decreasing, packaging consists offlexible polylaminate bags with a structured base.In the majority of cases, boxes are made fromwhite/grey retrofood cardboard weighing 320-330 gr/m2. Plastic bags and flowpack packagingare made of double film: OPP on the outside andcast PP on the inside.

Pest problems

Pasta factories, as any other food industry, canbe infested by insects, leading to negativeeconomic and commercial consequences (Süssand Locatelli, 1996; Riudavets et al., 2002;Trematerra, 2002, 2004; Barros et al., 2003;Stejskal et al., 2004). Considering the importanceof Italy as a producer and exporter, alimentarypaste has been the subject of much research(Frilli, 1965; Dal Monte, 1985; Süss andLocatelli, 1996, 1997; Trematerra, 2002, 2004).

Pasta factories use semolina, a raw materialobtained from hard wheat (Triticum durum

Alternative Methods to Chemical Control

749

Desf.), which comes directly from the mill.Because of the structure of the building, thepossible use of infested cereals and the largequantity of dust always present, semolina is themain source of reproduction and diffusion ofpests. Consequently, the same pests [Ephestiakuehniella Z., Plodia interpunctella (Hb.),Cryptolestes spp., Gnathocerus cornutus (F.),Lasioderma serricorne (F.), Oryzaephilus spp.,Rhyzopertha dominica (F.), Sitophilus spp.,Stegobium paniceum (L.), Tribolium spp.]present in warehouses, silos and mills are carriedinto the pasta factories where they can multiply.

Sometimes the pasta factory and mill mayconstitute an industrial unity where the above-mentioned species can also fly and penetrate intothe processing and packaging departments if thesimplest prevention standards reported in theHACCP procedures are lacking. Moreover,during the summer period some of these pestsare able to multiply outside the industrialfacilities, hidden under semolina encrustationsor on rejected products (Figures 1 to 7).

The first critical step in a pasta factory is toexamine the quality of raw material; however, itis difficult to detect an infestation that is inprogress. In fact, random samples of semolinaon large bags and trucks cannot be consideredreliable sources, especially in the case of eggsand larvae. The presence of Cryptolestes andTribolium adults on the surface of semolina canbe easily verified by inspection only when theraw materials come from heavily infested mills.Once the flour is purchased, insects and theirfragments are stored and become part of the firststeps in the processing cycle which is similar inthe pasta factory and modern mills.

It has been observed that kneading machinesand die plates, in particular, represent anunsurmountable obstacle to living insects andeggs. The kneading, subsequent pressure andstretching of the mass and high temperature donot permit insect survival. However, only insectfragments remain, testifying to the bad qualityof raw material or the infestations present in thefactory. From the desiccation process onwards,alimentary pasta can suffer from insect attacks

that are easily detected by consumers. Even whenusing the most modern desiccation equipment,alimentary pasta wastes often fall on the floor,especially at the end of belt carriers.

However, in the pasta factory, high temperatureand humidity favour the development of Blattaorientalis L., Thermobia domestica (Packard),and Musca domestica (L.); if moulds areparticularly conspicuous, saprophagous andmycetophagous insects, such as Typhaeastercorea (L.) and mites (Glycyphagus spp. andTyrophagus spp.), can also be observed.

Neglected places such as belt carriers, hoppersand electrical devices allow the growth of insects,which lay eggs on ensiled alimentary pasta. Shortpasta, in particular, stored for longer periodsbefore packaging can become heavily infested.Wood silos, which are common in Italy, providemany crevices in which insects can nest. Insectscan reach these places by flying or crawling onthe floor, pipes and on machinery.

The first barrier to pest infestation is the useof closed doors and windows. The risk ofpackaging infested alimentary pasta can occureven if insects are not yet present. Packagingdepartments must be kept clean and placed undersurveillance to prevent infestations.

Infestations (mainly larvae of P. interpunctellaand adults of R. dominica, Sitophilus andTribolium) can occur during the storage processin industries, warehouses, general stores andretail shops already colonized by insects derivingfrom other products. The shelf-life of pasta isparticularly long (in general 2 years, but also upto 3 years); in this period, insects can easilypenetrate into the packaging and reproduce manygenerations (Locatelli and Süss, 2002). Theyoften enter through the micro-holes that havebeen made to remove air during packaging. Theproduct can be attacked by P. interpunctella(larvae), R. dominica and Sitophilus spp. (adults)[mainly S. oryzae (L.)], L. serricorne and S.paniceum (adults) when it is placed on the shelfnear infested rice and other foodstuffs (Süss andTrematerra, 2003). In this respect, in a surveyconducted over a period of several years, it wasobserved that complaints and returns by

9th International Working Conference on Stored Product Protection

750

Figures 1-7. Died pasta (Figure 1); short pasta and spaghetti (Figures 2-3); funnel traps (Figure 4);insect marks (Figure 5); S. oryzae adult (Figure 6); shop (Figure 7).

customers were due to attacks generallyoccurring after the product left the factory.Inspections carried out in all of Italy, in severalshops where infested alimentary pastas were

bought (general stores, small and big departmentstores), showed that usually the stores wereneglected and the shelves dusty with infestationsin progress (unpubl. data).

Alternative Methods to Chemical Control

751

In Italy, pasta factories are usually subject toone or two yearly treatments of generalfumigation (conducted during April or August)using methyl bromide (25-30 g/m3 for 48-72hours); however, these treatments are generallynot sufficient to prevent the growth of infestations(Süss and Trematerra, 2003).

Opening doors and windows for degassing canfavour the arrival of adult E. cautella, E.kuehniella, P. interpunctella, R. dominica,Sitophilus spp., Lasioderma and Stegobium.Moreover, treatments with toxic gasses do notalways provide successful results. Often thestructures are inadequately sealed and gas doesnot reach the proper concentrations;consequently, results are unsatisfactory in spiteof high treatment costs.

Specimens of Sitophilus and Tribolium mayalso be present in the raw materials delivered.

Trends in integrated pestmanagement

The Integrated Pest Management (IPM)concept emphasizes the integration of disciplinesand control measures including biologicalenemies, cultural management, sanitation, propertemperature utilization and pesticides into a totalmanagement system aimed at preventing pestsfrom reaching damaging levels. Crucial factorsfor IPM in stored products include understandingfactors that regulate systems, monitoring insectpopulations, maintaining good records and usingthis information to make sound managementdecisions.

In recent years, new methods of protecting theproduction cycle have been introduced for theprevention and control of pests.

Constant monitoring of insects with differenttechniques and particular attention on behalf ofstaff prevent heavy infestations. Moreover, acontinuous inspection of raw materials has beenconducted by sampling semolina, using the filthtest, and by controlling companies’ supplies withon the spot investigations.

Prevention techniques were suggested, and in

some cases also applied, from ensiling semolinato die plates. This was accomplished bymonitoring Lepidoptera and Coleoptera withpheromone and food traps, by examining trackson dust, substituting wooden structures, sealingcrevices and by replacing screw conveyers withpneumatic feeding. Some elements in buildingdepartments and machinery were changed:gaskets were replaced. Crevices in which debriscould accumulate were sealed, walls edges andcolumn floor junctions were modified.Nowadays, however, the plan managers of foodindustries only rarely consider the problem ofmaintaining proper hygienic conditions, whichrepresent the first step in reducing pestinfestations. However, standard cleaningprocedures were modified and staff were trainedto clean the least accessible areas that aregenerally neglected and therefore sure sourcesof infestation. Big vacuum cleaners were usedto eliminate the accumulated dust. In fact, theremoval of debris is more efficacious than anylocalized chemical treatment.

Nonetheless, it was necessary to study howto reduce processing wastes and how to protectbelt carriers for unpackaged alimentary paste. Anintegrated method to protect alimentary pasteprocessing must involve planning engineers,foremen, mechanics and bricklayers.

In this context, the use of pheromones alsoplays an important role, especially in monitoringtiming. To control E. kuehniella, funnel trapsbaited with 2 mg of (Z,E)-9,12-tetradecadien-1olacetate (TDA) were used with good results inthe packaging department, and to survey P.interpunctella, sticky wing traps baited with 0.2mg of TDA were used in the processing andpackaging departments. Different types ofpheromone traps (Anobi-trap, Lasiotrap, Serrico-trap) have been used to verify the presence of L.serricorne and S. paniceum. Placed in differentareas of the pasta factory (processing department,packaging department, etc.), mainly near pastasilos, kneading machines and in warehouses,these traps revealed several hot spots of insectinfestation. These areas were treated by cleaning,modifying critical points and sometimes by using

9th International Working Conference on Stored Product Protection

752

localized chemical applications with synergizedpyrethrum or pyrethroids. A high number ofcatches generally occurred in the area ofalimentary pasta silos.

The use of pheromones to control T.castaneum (Herbst) and T. confusum du Val wasunsatisfactory. On many occasions, the numberof insects collected in the traps (Pantry Patroltrap, PC Beetle trap or Window trap) was inferiorto the observed infestation. In this case, properinsect monitoring through periodical inspectionsof debris, insect marks, as well as livingindividuals, offers many more significant results.The severity of infestation can be assessed byobserving the number and frequency of marks.To trap Tribolium specimens, better results havebeen obtained recently by using food bait trapsapplied in a study on the spatial distribution ofbeetle pests (Trematerra and Sciarretta, 2004).In this case, it was also important to clean andcarry out some localized treatments.

The articulated use of the above-cited methodsimproved the situation in pasta factories thatadopted this new method of integrated pestcontrol. The results obtained extended to otherItalian pasta factories reducing the use ofpesticides.

In several pasta factories, ProFume® isreplacing methyl bromide in fumigant treatments;other structures are introducing heat treatmentsas experimental applications in pest controlmanagement (Savigliano et al., 2006).

Despite these preventive measures, theproblem of pest attacks in pasta factories frompackaging to the consumer remains unsolvedbecause of certain aspects of used packaging andthe negligence of warehouses and stores inaddition to the long average shelf-life of theproduct. Warehouse managers and shopkeepersmust be involved in this processing cycle byencouraging frequent visits on the part ofinspectors and the distribution of bookletsconcerning the problems and their possiblesolutions. In the meantime, potential newpackaging methods that are less susceptible topest attacks must be studied.

Only by controlling the entire processing

cycle, from the purchase of raw material to thedistribution of the finished product, will it bepossible to reduce the risk of infestation.

References

Barros, G., Maia, A., Rodrigues, A., Mexia, A.,2003. Stored product insect pests in pastaresidues in Portugal. Proceedings 3rd

Meeting of COST Action 842-WGIV,Berlin, 48.

Dal Monte, G., 1985. La difesa delle pastealimentari dagli insetti. Ministerodell’Agricoltura e Foreste, Roma, 1-67.

Frilli, F., 1965. Le paste infestate. Indaginesulla frequenza degli insetti dannosi e deiloro parassiti. Molini d’Italia XXI, 247-257.

Locatelli, D.P., Süss, L., 2002. Capacitàattrattiva di pasta di semola nei confronti dilarve di Plodia interpunctella (Hbn.) e diadulti di Sitophilus oryzae (L.). Atti 7°Simposio “La difesa antiparassitaria nelleindustrie alimentari e la protezione deglialimenti”. Piacenza 2002, 163168.

Riudavets, J., Lucas, E., Pons, M.J., 2002.Insects and mites of stored products in thenortheast of Spain. IOBC wprs Bulletin 25,41-44.

Savigliano, R., Minuto, A., Camponogara, A.,Savoldelli, S., Süss, L., Gullino, M.L.,2006. Bromuro di metile: eliminazionesenza rimpianti. Informatore fitopatologico3, 31-35.

Stejskal, V., Kucerova, Z., Lukas, J., 2004.Evidence and symptoms of pasta infestationby Sitophilus oryzae (Curculionidae;Coleoptera) in the Czech Republic. PlantProtection Sciences 40, 107-111.

Alternative Methods to Chemical Control

753

Süss, L., Locatelli, D.P., 1996. New trends inpest control in an Italian “pasta” factory.Proceedings International Forun, Storedproduct protection and post-harvesttreatment of plant products. Council ofEurope, Strasbourg, 171-177.

Süss, L., Locatelli, D.P., 1997. Attività diSitophilus oryzae (L.), Rhyzoperthadominica (F.), Tribolium confusum du Val ePlodia interpunctella (Hbn.) su pastealimentari. Atti VI Simposio “La difesaantiparassitaria nelle industrie alimentari ela protezione degli alimenti”. Piacenza1997, 47-55.

Süss, L., Trematerra, P., 2003. Tecnicheinnovative per la disinfestazione di derratee industrie alimentari. Informatorefitopatologico 10, 44-50.

Trematerra P., 2002. Practical use ofpheromones. In: Integrated management ofinsects infesting stored cereals and pasta.Proceedings II International workshop“Durum wheat and pasta quality: recentachievements and new trends”, Rome2002, 119-125.

Trematerra P., 2004. Integrated management ofinsects infesting pasta factories in Italy.Proceedings 5th Meeting of COST Action842 WG4, Barcelona, 31-34.

Trematerra, P., Sciarretta, A., 2004. Spatialdistribution of some beetles infesting a feedmill with spatio-temporal dynamics ofOryzaephilus surinamensis, Triboliumcastaneum and Tribolium confusum.Journal of Stored Products Research 40,363-377.