Disinfestation of Copra, Desiccated Coconut and Coffee Beans by Gamma Radiation

Report No. IAEA -R- 3098-F

TITLE Disinfestation of Copra, Desiccated Coconut and Coffee Beans by Gamma Radiation

FINAL REPORT FOR THE PERIOD 1 May 1982 - 31 January 1986

AUTHOR(S) E. C. «anato

INSTITUTE Philippine Atomic Energy Commission, Diliman, Quezon City, Philippines

INTERNATIONAL ATOMIC ENERGY AGENCY DATE August 1987

ti DISINFESTATION OP COPRA, DESICCATED COCONUT AND COFFEE BKANS BI GAMMA RADIATION B.C. Manoto» L.R. Blanco* A.B. Mondoza and S.S. Rosilva Philippine Atomic Energy Commission Diliraan, ijuozon City PHILIPPIiWS

ABSTRACT Sovoral posts wore observed attacking copra in storage, the most prevalent of which is the eopra beetle (CB), Nccrobia rufipes DoOoor. While in coffee, the coffee bean weevil (CBW), Araecorus faaciculatua DoQoor showed preference for arabica, liborica and excolaa varieties but none for robusta coffoo. *W mass roaring, the most efficient diet for CB was a combination of desicoated coconut + yeast (2*1) and for CBW, dried cassava chips + yeast Oil). Using the above diet, the life cycles wore completed in 43 to 60 days and **2 to % days in CB and CBW, respectively. Irradiation studios for the 2 species showed the eggs as the most sensitive followed by the larva and the pupa. A dose of 0.05 kGy prevented adult «ncrgonco from irradiated eggs and younger larvae while doses of 0.10 to 0*25 kfly were offoctivo in eliminating adult survival from irradiated older larvae and pupae* However, a dose of 0.50 IcPy would bo effective for disinfestation of small packages (0.25 to 0*50 kg) of eopra or coffeo beans initially infested with iamature stagos of CB or CBW, respectively. Also, packaging of irradiated cosnodities in polypropylene bogs particularly those impregnated with peraetkrin prevented roinfostation by the insect posts* Toxic rosiduoa of per- taethrla in the propylene film resulted in high insect mortality thereby preventing insect penetration of the packaging materials* Both CB and CBW were rather good invaders rather than penetratora since these speeioa onterod packaging materials readily through existing openings in jute sack, woven synthetic polypropylene sack or flour bag* Orga» noleptic tests showed no change in aroma, flavor and general acceptability of irradiated coffoo beans*

desiccated coconut, a maximum dose of 6.0 kOy would be required to eliminate Salmonella entoritidls* COeoout and coffoo beans are two of the dollar generating commodities of the Philippines* Copra, one of toe chief coconut product of trade, ranks next to soybean as the world source of oil (ttoodroff, 197O)* According to the report of the Philippine Coconut Authority (PCA) in 1985« the value of copra and related by-products exported to different countries anounted to about US$551 million. Qn the other hand, the export value of coffee beans in 198^ was approximately VSt?1* million from a total of 35,000 metric tons of beans (basod on the annual report of the Bureau of Plant Industry)* While the trend for world doraand of copra is decreasing, it is oxppcted that in the ensuing years, earnings from coffee beans will even surpassed that of copra. Rowovor, both copra and coffee beans ore susceptible to infestcition by pests and microorganisms* For instance, desiccated coconut, an important coconut product, is infected by a number of microorganisms, particularly Salmonella enteritidis. Some shipments contaminated with this pathogen were condemned and rejected, causing tremendous losaos to exporters* For this reason, the PCA adopted a «oro mioroblal count as a requirement for all desiccated coconut intended for export* Likewise, copra and ooff00 beans are beset with numerous insect posts which lower the fuolity of the products* IhO most serious insects are the copra beetle, Nocrobia rufipos do Q* and the coffee bean weevil, Araocerus fasciculatus de 3, Xn this regard, on effective method of disinfesting those commodities was doomed nocodsary to minimise losses and improve their quality in order to IM more competitive in the world market* Various chemicals and fumiganis are currently utilized to control the posts but tholr use poses certain environmental and hftalth problems* Honco, alternative method hod to b«i looked into* Th* UM of gamma radiation for disinfestation of various food and agricultural products, have boon oxtonsively studied in many countries and results showed some promise (Cornwell, 1966, Tilton and ftrowar, 1973, liitoa an* SunUtt,

1933, FDA9 19Ö1). Sho main thrust of this projoet, therefore, is to establish on effectivo disinfostation dose for oopra, desiccated coconut and coffee boons* Specifically, this project hail the following objectives» 1* ?o survey the incidence of insect infestation in copra and preference for certain variety of coffee beans by coffee boan weevil* 2» To find offective roaring media fir copra beetle and coffee boan weevil* 3* 1O determine the biolosy/life history of the copra beetle and coffee bean weevil* k» 'i'o study the effects of gamma radiation on survival rates of different immature stages of copra beetle and coffee bean weevil* 5* ^o determine the radiosonsitivity of Salmonella ontorltidia in dosi- efcatod coconut. 6* Vo conduct organoleptie testa on irradiated and uhlnradiated coffee beans* 7. 'fo evaluato the offocta of different packaging materials in protecting irradiated eoaoodity from relnfestation*

MATBSlALS AND METHODS ty and Incidonce of Posts , / Samples of copra, were eollocted from different copra warehouses throughout the Philippines through the assistance of the Philippine Coconut Auhtority (PCA)* About 5 to 10 kg~saaples of copra wero taken at random from 2h different warehouses and subsequently brought to the laboratory for examinations* 'fhoso wore weighed and placed in aualin sack or jars for weekly counts of pests* Identification of the posts

«as done by the rosoorchors or sent to the Department of ftttonology» University of the Philippines at !«os Sanos for further verification of Identified species* With coffoe boons about l«kg samples for each of the coffeo species.

i*o*t Arabica. Hobusta, fixcelsa and Uborica - ware obtained from BatoBflBSt a province south of Luzon Islands* She coffoe saaples wero brought to the laboratory, weighed and placed in synthetic propylene

sack» One aonth oftor collectiont coffee bean weevils wore counted. Monthly counts wort» done for a period of 3 months.

Bforing and Biology Studi«e In tho preliminary studies, 7 diet combinations wore tried in rearing the copra beetle (CB) and these woret (a) copra alone» (b) desiccated coconut (DCN) + yeast (T), (e) OCN + Rabbit pelL»t. (d) flour + Y, (e) copra raeal + Y, (f) DON + fish meal and (g) DCS + toxturizod vegetable protein (WP). In the later atago» the diet combinations were roduced to h and these wore: (a), (b), (f) and l(g)« On the other hand» for the coffee bean weevil (CBW)* the foliowing media wore tested* (a) whole coffee beans» (b) whole coffee beans + Y, (e) ground coffee boons + wheat germ (ivG) + Yj (d) ground corn + IVG + Y and (•) ground copra pellets + 'HQ + Y.anLfttofr |n 1984» a iaodifiod diet combination was tried based on the work of Santos at tho JjIOTHOP, Indo- nesia (Unpublished» 1983)* firied cassava chips + yeast waq prepare^ at 3il ratio using either yellow or white cassava variety. 'tf ^o test tho best rearing medium» the criteria used worot % adult emergence and duration of developiaent from larva to adult/ Tho developmental stages of CB and CBVV were studied microscopically using ai dissecting compound Bauach and Lomb microscope* : ;\,vj Stock Culturea of CB and CBV/ \ Adults of copra beetle were collected from the warehouses of the

•f1 ••' Philippine Befining Co. and Philippine Coconut Authority froth located \ '. in MetroManlla. '^liesa were mass roared in ball jars using DCN + Yoast \ \ (£jl W/W). For CBW » samples of infested coffee beans iroi'o bought from \ some provinces in Southern Luaon whore coffee is grown! and brought to \ I \ tho laboratory* The adult CBW were transferred to plastic containers \ and provided with a mixture of dried cassava chips and yeast (3il)«

Pro-irradiation Treatment Fifty adults of OB wore each confined in plastic oontelaers provided with 300-gm DCN and yeast tatsturo for egg deposition» Aftor 2V30 hrs» the booties wore removed and the diot mixtures containing tho eggs woro kept in screened shelves until the samples wore ready for irradiation* 'or CBW« 30 adult* wore collected from the stock culture and confined in plastic jars containing approximately 300*gm mixture of cassava chips and yeast for egg deposition* She weovils wore removed 3 days after and returned to the stock culture* The jars containing the eggs were maintained at room temperature until the different stages and ages of CBW were ready for irradiation» Irradiation All irradiations were done in the Cobalt»60 Öaiaaacoll 220 facility at a doao rate varying fro» 31.8 - 32.2 Gti/m&n, For GB, eggs wore irradiated at 2 ago groups* 1-2 and 3*4 days after egg deposition. She larvae» wore irradiated at 1-2, 7-8, 1^-15, 21-22 and 28-29 days while the pupae wore treated at 3-4 and 6-7 days. Doses used were 0.01, O.O25t O.Q5, 0.10 and 0125 kffy. On the other hand, for CBW, tho dosos were 0.025* 0.05, 0.10 and 0.25 kfly. Jaggs wore treated at 5-6 days olclj tho larvao at 4»5» 7-8 and 13-14 days and the pupae at 2-3 and 6»? days. All treatments were replicated 4 titties with 2 replications done on tho same day* An untroated batch served as the control lot*

Post-Irradiation Treatment Both irradiated and unirradiated samples of CB and CBW were kept in aluminum-screened shelves to prevent any contamination of unwanted insects* ffiio hutnber of adults that omorgod from each of the treated and untreated batches wore recorded after pre-doterrained tine intervals based on the biology of the insect* Similar procedure was adopted for CBS* She number of emerged adults froo both treated and untreated batches was tho criterion usad for survival rates of the test insects*

Hiarobial Irradiation 7 Cultures of Salaonolla onteritidis were isolated from DCN which was obtained from PCA and cultured in the PABC microbiology laboratory* A 48 - hour culture of the organisms was grown in nutrient ogar ooditta and a loopful of tho bacteria containing about 1 x 10 colls was inociilatod into 100-8» samples desiccated coconut contained in polyothyl«no plastic bags* Inoculated samples were irradiated at 0*5, 1*0, 1.5, 2.0, 3.0, *t*0, 5.0, 6*0 and 7.0 k% at a dose rate of 31.8 Oy/rain. Appropriate serial dilutions in nutrient broth were made a day after irradiation» from the sample, the number of surviving cells was recovered in nutrient agar medium in parallel with selection media such as Lovino Sosin M»thyl*n« Blue agar, Brilliant Qreen Agor, Bismuth sulfite agor, «14 Saio AgoT using tho plate count method. AU raodia wore propared as spooifiod tn accordance to tho BBL Manutl of Laboratory Products and Procedure, Plates wore lncubatod for 48 hours at 370C boforo scoring typical colonies.

Organoloptic Seats on offocts of irradiation onoaroraa, flavor and general acceptable lity of irradiatod and unirradiatod robusta coffee «roro dono at the College of HOMO Economics, University of tho Philippines (Sabuscado, I983). Coffoo DOWrO(SO was prepared by placing 60 gms of troatod or untreated ground coffoo in a porcolator containing 1000 ml of water* This was browed for , 5 minutes. fifty*gras of sugar was added and disolved in tho coffoo beverage* Then both control and irradiated bovorages wore subjected to sensory ©valuation by solootod panollsts for odor, flavor and general acceptability following tho 9-point Hodonic scalo. Choice of panelists was based on the consistency of their evaluations during the prolininary test and some basic questions on their drinking habits.

Penetration Studies ;: the penetrating efficiency of tho adults of both CB and CBW was " determined by using 5 different packaging materials. The test tutorials ", used worei jute or gunny sack (JS), woven synthetic polypropylene sack (WSPS), flour bag (cheesecloth) (FB), pernethrin treated polypropylene (PPP) and untreated polypropylene film (UPP). The PPP films wore made of polymer consisting of an outer layer of polypropylene containing technical pormethrin at 203 fflg/a , a middle layer of polypropylene plus polybutylono adhesive and an inner layer qf polypropylene. The PPP and the Upp were Ul»8u and 109.au thick, respectively. These propylene materials wore provided by Qr. Henry A. Highland, Stored Product Insects Research and Development Laboratory, Savannah, Georgia while tho first 3 materials were produced locally. Two experiments wore made In determining the penetration studies* In iho first oxperiaont, the packaging materials were cut into 13*5 x 8»5 «n paokets and tho sides wero sewn or sealed depending upon tha material leaving one end open. £aeh packet had a final size of 12*5 x 7*5 edi and provided with or without food» Afterwhieh single adult CB or CBW was placed inside the packet and the open end taped securely g>§ with clear cellophane or masking tape. Each packet was placed in a vertical pssition inside a 900-al plastic jar and covered with muslin cloth held tighly by a rubber band. In experiment 2, each packet of the five packaging materials was provided with food and then sealed with cellophane or masking tape. AU 5 packets were placed inside a 2-1 plastic jar into which 10 adult CB or CBW ware introduced and then covered with muslin cloth. Observations gathered on the penetration of adult insects and the

percentage mortality were done at 1( 3i 5» 10» 20, 30 and 40 days from the start of the experiment. Dead insects were recorded and replaced immediately by live adults obtained from the stock culture. The individual experimental tests were replicated 4 times.

Storage Tests on Irradiated Commodities Bags measuring 38 x 24 cm were prepared from the five different packgfing materials mentioned above. On the other hand, clean copra or coffee beans were placed in plastic container and provided with 30 adults of copra beetle or coffee bean weevil, respectively. Bach container was covered with muslin cloth and the adult insects were allowed to lay eggs for about 2 weeks. Afterwhich, the adult pests were removed while the infested commodities were kept for another week. Irradiation was done on the 4th week using a dosage of 0*25 and 0.50 k(Jy. While untreated batch served as control. After irra- diat ion, about 0.25 to 0.5 kg of the commodity was placed in individual •. 'vV; packaging material and stored for i months. >V Observations made on the number of live and dead insects were yp,< done on a monthly interval for a total duration of i months while anothe»-;^ batch was kept sealed and opened only on the sixth month after treat- fpi*^ ment. Experiments were replicated 4 times with 2 replications done :-''•*:; on the same day.

RESULTS ANi) DISCUSSION Survey and Incidence of Pests Nine insect pests were oolleoted from copra samples gathered from 24 warehouses located in 14 provinces in the Philippines* Copra beetle, Mecrobia rufipea; saw-toothed grain beetle, OryMaephilua surinaaensia; red flour beetle, 1'riboliua cestaneuat foreign grain beetle, Ahaaverua advena; corn sap beetle Carpophilua fliaidiatus Fabr.f cigarette beetle, Laaioderaa aerricorne; tropical FV * warehouse moth, Ephestia cautella; unidentified earwig} and paocid, Liposcelis divinatorius were collected from the different saaples (Table 1). A speciss of aite, Suidasia aedanensis waa collected and found aost abundant in the culture from the months of August to October* This species was observed attacking both copra and coffee beans* The most prevalent insect species observed in Luzon was the copra beetle (Fig* 1) followed by the saw-toothed grain beetle. However, the reverse waa observed in the Visayaa islands* Such findings are contrary to those reported by Graza (I98D who observed copra beetle aa the most abundant species in all warehouses in the 2 towns of Leyte. The difference in our findings may be attributed to the stage of the copra samples* In this study, the saaplea were relatively older aa evidenced by the appearance of the copra which showed numerous insect holes and the presence of molds. Psocids were most abundant with samples obtained from Mindanao Island. The saaples were drier but aoldy compared with those collected from Luzon. No differences, however, were observed on the populations of copra beetle and the saw-toothed grain beetla. In all the 3 Major islands, earwigs, tropical warehouse moth, corn sap beetle and the foreign grain beetle were found in lessar numbers. However, corn sap beetle and foreign grain beetle ara generally fungus feeders and are subsequently not considered aa pests of copra. On the other hand, the GBvV (Fig. 2) exhibited certain preference for aome varieties of coffee, Arabica, Libericu and iSxcelsa coffee varieties were more prefered as hosts than the Robusta coffee (Table 2), However, the factors responsible for aaoh mechanism of reaistance offered by robusta variety, has not been studied since it ia not within the scope of the investigations.

•m Scaring and iiiology atud.i.es The most efficient rearing medium for CB was a combination of DCN + yeast (2:1) based on a mean of 95 «2Ä adult emergence and shortest duration of V/-42 dcys from larva to adult stage (Table j>)< For CBlV, dried cassava chips + yeast (3:D was found the best and the least expensive. The total cost «f the diet is ^0,17 and is sufficient to culture a total of 7^0 adults. The above diet combinations were used to study the different life cycles of CB and CBtV (Table h), Duration of the different larval instars were not determined although Alpuerto reported 5 instars for QB (1979). Aside fro» coconut products» CB has been reported co infest 28% of dried fish produce in Nigeria (Gsuji, 1975)«

Survival rate studies: A. Copra beetle The survival ratas on the different ages of egg, larva and pupa of copra beetle are shown in Tables^. Among the immature stages, the eggs are the most sensitive to radiation damage. No adult emergence was observed when eggs were treated at O.C5 IcGy and above. The 1- to 2-day old eggs were more sensitive than the older eggs (5- to '••days old). These findings coincide with the results obtained on radiation effects on *ggs of aost species of stored product pests (Cornwell, 19*», Tilton et nl., 19*». Ahmed, «t, ai., 19?6). Similarly, a dose of 0.0;? kCiy and higher dosages caused lVO* death among the younger larvae (1- to 13-days old) although some older larvae survived and reached the adult stage. The results indicate that radiosensitivity of a certain aetnmorphic stage depends on the developmental age «f the insect during treatment, i.e., the older the insect within the same developmental sta;;e the •ore resistant they are to radiation damage. However, since the adults observed were already dead upon examination , it appears that death was delayed, survival rates for the pupal staje of CB followed similar pattern with those of the larva, /or a zero survival* a dose «f 0.10 ktiy was found effective for younger pupae (;5- to '••days old) but a «uch higher dose of 0.25 luiy was required for older pupae (*»- to 7-days old)* B. Ooffoe bean weevil The survival studies on fasciculatus are shown in ^able 6. Adult recovery after irradiation of immature stages wore found to be similar vsrith the aforementioned apeeios. %£> number of adults recovered from tho treated samples decreased progressively as the dose was increased from 0.025 to 0»25 Wfy» Irradiation of 5- to 6«day old QQQS and 2- to 3-day-old pupae with 0.05 k% and 0.25 ^yt respectively, prevented ad!j"Lt emergence. Some older pupae (6- to 7-days old) at a dosage of 0.25 k^y poached adult stage but thoso were deformed and subsequently died. '. %airiination ,of the adults showed some abnormality in wins formation and a/alight color difference in outiolo pigmentation. Similar results were/observed by Donate (Personal communication) in another laboratory but jcraatment was at 0*12 k% on mature larvae of CBWa Apparently, some/I changes in the molecular level of the somatic colls were induced by radjlation during treatment and thoso wore manifested only In tho adult. Furthernioro, the lethal effect on the organism was not immediate b^jt occurred during the next metamorphosis. / Adult emerjjonco was completely stopped when younger larvae ('t- to /8-days old) and older onos (l>- to l^t-days old) w«re treated at 0.10 köy •'' and 0*25 k%, respectively. Since no actual examination was done when mortality occurred» it could be assumed that death occurred during the late larval or early pupal stages* Hence, a dose at 0.25 Wy is found affective in controlling infestation in copra and ooffoe bean*. However» Loaharanu et ai (197F) suggested doses of 0*50 kSy and higher, while Hoodaya (198^) stated that doses of 0*10 to Oc1K) kQy wore sufficient to control infestation by A* faaciculatus» %ic use of gaotna radiation would be useful in destroying internal feeders such as N. rufipos and A. fasoloulatua since the uso of pesticides aro rostrlcted duo to th» finvironnontal Protection Agoncy requirements and sorae pesticides» l«e«, pirimipho*-raothyl «as found ihoffoetivo for tho latter (Baylor, ot al, 1978). While tho uso of irradiation (at 0.25 • köy) may not have fast acting ability as compared with aorao chemicals» , insect dovoloptnont was clearly impaired. Death of the insects may be I' attributed to some ohooieal changes brought about by direct and indirect ' effects of radiation within the organism. In addition, radioaonsitivity 10

was found more evident in the younrjor a;;;es than in the older insects within the some iaetamorphie stage. '-The results obtained aro in agree

ment with several insects studied so far (Arauh, 1977» Potter, ot a\,t 1976, 1980, IAEA, 1970).

Hicrobial Irradiation ? shows the recovery of iri'adiated and non-irradiated ,§• ontoritidia in various plating media. Analysis of the results shows no significant difforc-ncoa between the irradiated and non» irradiated sataploa on the level of microblal destruction at 0.5 with Levine iSosin Methylone 31ue Agar and ländo Agar as the recovery media* This similarity could be abtributod to tho presence of other gram negative enteric bacilli like those of the dysentery groups which hav,e tho saino color reactions as those of Salmonella» However» in or'der to verify that no other species was involved in the experiment» the samples wore cultured in Brilliant ^een Agar and Bismuth Sulfito Agar» Sheso media are specific and. diagnostic for Saliaonella» honco no other groups of enteric bacilli will grow» Similar results wore obtained when Nutrient Agar was used as recovery medium. A significant decrease in tiie number of viable count was already observed at 0*5 and further reduction was noted as tho dose was increased from 0*3 and above* Several studies (Anellis» et al., 3.972; Loy« 197?i Karapolmaciior, I981 and Ouworkork, 198l) revealed that a dose botwoon ^.0-10 köy (O.'t-l Krad) is sufficient to eradicate iaolaonella populations of 10-10 per gram. Similarly» our results show that a maximum dose of 6*0 kQy is sufficient to eliminate completely S. gntorltidia in doaiceatod coconut.

Organoloptic organoloptic tests on irradiated and unirradiatod coffee baans is shown on Table 3* No distinct differences wore observed by tho panelists with regards to the aroma» flavor and general acceptability between untreated and treated (0.25 and 0.50 käy) cofi'oo. Howoror» a similar study conducted by the Bureau of Plant Industry showed that irradiation at 0.15 kQy affected tho quality of oxcolsa coffee while a enhbnaement of both flavor and aroma was observed with irradiated 11 robusta oof.Coo (Crisostomo ot ai, unpublished report}* In anotiior t«at oonduotod by Dias* ot ai (1977)» ho lndicatod a change in flavor In ono out of 12 samples of ooffoo Irradiated with 0.25 kGy although the result was not significant» $he discrepancy obtained may b« duo to differences In drinking habits of panelists selected for the teats or the variety of coffee beans usod in the evaluation» Although several work on organoleptlc evaluation of products irradiated at 0*25 &*y and bolow did not show any significant effect on the characteristics. diseuasod earlier (Murray, 193.1). However, one limitation of the teat was that the panelists although mostly coffee drinkers are not used to brewed coffee but to instant or soluble coffee*

Penetration Studios In the first experiment, the moan percentages of adult CB and CBlV that penetrated out of the 5 paqka^lng materials tested are shown in Sables 9 and 10, respectively» It was observed that no adult of both species were able to penetrate oifchor of the treated (PPP) or untreated polypropylene bags (UPP). However, with CB aorae (mean of 3*? and 2,8$) adults were able to enter through broken seals or tape as shown in Xablo 9 at 20 and 30 days from th;o start of the oxperitaont. However, both species may bo considered good invaders since adult CB and OBW were able to pass readily through jute sack but less readily through woven synthetic polypropylene saclc. According to Hifjhland and Wilson. (1931) and dine and Highland (I98I) some oocnon stored product apociea which they considered invaders enter packages through existing openings. Iho species include the flour beetle, ^rlbollua spp. saw-toothed beetle, Oryaephilua aurinamonais and flat grain beetle, Oryptolostos pusillus» Furthermore, they observed that mosp of the adults of stored product ooleoptera can pass through holes as small as 0.33 am in diameter although the 2 species tested in this study were not raentioned by the said authors» \ Ih the above packages, openings Which varied from 0,2 to 3 mji served as points of oxitfcsfor the species tosted» With rosaeds to the / flour bag which was the most insect roWstont among the three packages^ , the seams were likely exit sites used by the adult insoet* '^hO mean % mortality in. the aUuIt CB and CBW aro shown in '-tables U and 12« Higher peroenta^os of adult CB and CBV/ were found dead Inside the permethrin-treated polypropylene (ppp) bags» !Qio inaoetieido residues apparently caused the death of the insects Inside the film thus preventing their escape from the packages. The results also indicated that the insecticide was still effectivo after almost h years indicating a long residual life» %ua» it would be necessary to conduct residue studies in the packaging materials and in the comtaoditics stored in those packages, For multiwall kralt bags, Highland «t a^ (1934) »•«ported the persistence of poraothrin residue on tho plioa of fillod ba$s and> instant CSH (ICSM)< a high-protein cereal blend containing cornmeali» soy flour, dried milk, vitamin and minerals, '-öiey observed pormothrin moved or do&radod very slowly such that after 2& months» most of tile original treatment still remained in the outer ply. "'hile in the untreated polypropylene bags, the absence of oxygen and probable accumulation of carbon dioxide led to the death among- the insects which emerged inside the packages» However» the observed mortality in the OPP did not differ much from those of JS, WSPP and FB. Under experiment 2» none of the CB or CBlV was able to penetrate neither treated (PPP) nor untreatod (PPP) bags (Sables 13 and 1*0» Howeveri Invasion of the other packaging materials was obswvod at 3 or 5 dajrs» respectively» from the start of tho experiment* She results clearly indicated that both species are poor penetrators but are good invaders of existing openings* scam or untight conditions in tho packages. 1W results further verified earlier observation on the effectiveness of tho pormothrin treated polypropylene film in preventing reinfostation of treated commodity, She experiment also verified the importance of using insect-resistant materials in protecting raw or processed commodities from insect damage»

Storage Joat on Irradiated Commodity in paqkafiing Material» then copra was irradiated and 3tored in any of the 5 packaging materials, tho combination treatments of irradiation plus storage In insect resistant packages was found effective in protecting tho copra from insect damage ('fable 15). xhe use of «ither 0.25 or 0*30 kdy •m 13

greatly reduced ndult emergence of any immature copra beetle present within the commodity during treatment while storage In insect resistant ' packaging materials prevented roinfestation of the said commodity. , However, when copra was stored in polypropylene bags most of the copra ; became moldy so that at the end of the 6-month observation period, • the copra was no longer suitable for processing. *%us, if such material [ will be used for packaging, the commodity should be properly dried ' and aerated before closure ' - On the other hand, with coffee beans a dose of 0«50 käy would bo required for treatment before atcrago in insect resistant packagos * (Table 16). 'lhis will insure death among immature stages that may bo present within the beans o# if some late pupae survived the treatment, 0.50 kfly • will be sufficient to effect death among the emerged adults a few days k or wooks after oeloaion* Baaed on the data collected, some roinfestation was observed on the ^k month after treatment» '-ftie untreated sample | was suspected to be the source of rdinfostation. furthermore, raito '• infestation was not prevented by any of the packaging materials used '' in thl3 experiment» At the end of the 6-month observation period, =: relatively large mite population occurred among both irradiated and *; unlrradiatod sanplos although fewer witos were observed in samples packed t in propylone materials» ?hus, our observations indicated that these |< packaging matorials provided better protection from reinfestation by £ r;i insects than did other bags during the 6-months storage periodi : CONCLUSION

A dose of 0*50 kOy vvoulf be effective for disinfestation of small packages of copra and boffeo boanfc initially infested with irattfitive stages of copra boejfele and cof^oe bean weevil, roapoctively. Also» storage of those irradJLated commodities in polypropylene fUa particularly when impregnated with pormothrin prevented roinfostation during the 6 months observation period* On the other hand, a aaxinua dose of 6 kQy would be required to eliminate completely Salmonella qntoritidis in desiccated un

Afeoftä, M., A.D. laulyan, A.M.8. AlM, aaa a«M.i. Mttda. 197«. tadlottoa dlaiafootatloa in oaa- drtod floa. Proo. «pop* flok Vtilioatloa looteolosr OJMI Markottag Ia ftdo poltto flaaorioo *ofio»» dI S-U mreh 1978« Alpaorto, V«V. X979* furvogr of iaooota assooiotod with otorod oojra* B.S. «hootof UnIv. of tao PalllpplMo at IM lofloo, l t X.X.A. 1977. OoMtrol of yoot lafootatioa of food oy imiiatlM* Hei, KPoaorvntiMi by IrmdUtioo 1 «197-206. Ana«li*»A.»D. Bortmritet »• «ooatak a»J 0« ftrojw* 3L9?2« ladlatloa •to»Ulamtioa of troUtn» MUitswy loodat Low Tooyf atwo Irr«4l«tioa of Ooifloa 9olw, Oomod Boof« «a* fork «oMoaso. Ia Auli* Mloroblol. 4^5^ » L.D. and I.A. Highland. 1981« Malflua olao of hoi», ollowiag foooofo of adulto of otovod product oolooptora* J.lo* l>toax>l» *oo. 16»525-351. Olt F.B. (od). 1966« tho Äatoaology of Radiation DioiafootatlMi of Qbrain» 236 pp. fr&Mon, Oxford*

OPlooo«oao*I.»e.f R. DlMtO and A.C. Oaboaap* 1964« Study on tao offoeto of irradiation oa tfao qiwli^r and ototrago poat of ooffoo boaao* Oapuollofeod Xoport, 5 pp. Mao* M*» I* loahagorm aad Xi. Vokac* 1977« «hangoo in flavor and taoto of Inradlatod ooffoo ooaao. Food Pfooorvatloa oy Xmdlation. % lrtwooaio, K.I. 1983. ttm offoot of inadlaUoa on tao flavor «ai of ooffoo ooaao fOoffoo gooaota 1.) ISA (Food oad *n* AiMaiotvatloa) 1981* foliojr for «maaUtod foodoi Advaaoo aotioo of ftojoood jrtMiwi for tao goplatli of irra* «latoa food for taoaa oonowoHioa. IMU Bog», **oh 27. 46(

•NUM. O.D. 19*1. tojrvoy «ad iaoaUfloatioa «f ooje» laaott paota w ooroaowata 1» Oraoc and Ia iayoajr» loyto. B.I. laoota, Vloayao «toto Oollofo of Uyt«. mm, I.A., I.A. H-loltlo, ud H. Boatriiat* 19M» Zaooottoiao- troatod fila «rap «o protoot oaall faokojjoa froa lafootatioa* aooa« aatoaol* I.A. aad «. Wm*. 19tL. ltoiatoaoa of polyaor fila. to poaotratloa oy loooor «rola ooror aad dooorlpUoa of a dorloo for aoaoartHg roaiotaaoo. J* looa. litoaol. 7^107-70. loooaya, M. 19»%. ladiatioa dlaiafootatloa of tobaooo loavoa aad -7 ooffoo bouM. food tnmi* looolottor «(1) «20-21. I . f latamtloua AtMlV 4NNW Agon«y* 1970. Srolnliig Ifmwa] OB Xm41*tf«« **«nMlat7 an* lq fttfctitaX Xoyprta N*. Ut* Vltnaai JAlA Ik FAO. XSk B.H. 1981« WWfeeta of lliaiaating Pathog«i kgr «te of food XrratiatiMu »p. 265-289. Qbll > ro04 Igf*Uttioa» Vol. XX* Sit. Ateaie liiton, B.W. and J.K. Ivomis 1973» ttataa of 0.*. Baft, of g »••••reb 00 irradiatita dtatafaatatlon of «jnln and grain yroaoeta* Xn Badlatiot Praaorration of FoodL p. 29?« Oonf• Free* aoabay, Intl» Atoaie laarsf *8«noy» THton, J.f. and A.X. lurdatt. 1983* XnMot «Udafoatatloa of grain and fruit* Xa Froaorvatlon of Food by Iaalaiag ladiatioa. ToI* 3t l«i« Jk>atphaea and M.S. Potaraon. Ms» Booa «stout QIO gr»aa. J.Q. 197O-. Ooeooutai Froduetst grooaaning Produeta. lho v 0o« Inc. oatjpolntt Oonnoatieut* Necrobia rufipes (Deg.)

5 mm

Copra bMtla

Fi,;. 1. '/opro "o<.--- <-•--, f.-crobia '• *••• Araecerus fasciculatus (Deg.) •

Fi-. vil, «raecorua fasciculatus Maan auabar of «ojtra paata.oallaotaä' Aroa t)M J aajar

WtKTPMt 1080« VXtATAS MHIDAIAO

Qapra aaatla 28.0 b 25.5 b «.-«» Iaa-taataa4 grain aaatla 24,8 b 5Ma 28.0 b Amiga grain aaatta 10.8 « 11.0 d 22.5« flam a*f aaatla 0*0 o 2.8 a M 4 flaw 9.3« U«0a 2.2 4 1*6 a «omlg 0.0« 0*6 a 0.0 • faadU 0*0 a 29.0 b 92.5«

Aate aara aab jaata* ta 1/ X*0.5 traaafavamtloB lar atatiatiaal «aalyaia. Manna Ia aaah aoluaa. aot abariag a aeaain lattar «ra 4iffavant at taa % laval (öuncan*. «ilUfl» raaga taat)*

Vabla 2* Arayaga anaaar of eoffaa baaa «aavila praaant ia k aeffaa apaaiäa aariag tha 3 aoath ebaarvatian f«rio4*

QOfFIi MfMIM 15*8 i 1.55* 20*8 Z 1.51 15.5 * 1*52 Robuata 3*8 - 0*98 2^ i 0*81 k*0 £ 0*78 13.0 2 1*01 22*0 * 1*25 17*0 £ 1*35 Ubarlaa 15*8 2 1.19 15.0 £ 1.42 17*2 - 0*91 tao!» 3« If foot of widcNu «lot «oablaatioM on adult of tho oojra battle «ad tb* eoffoa boast mwvil.

»1ST Adalt

00|M 90*2 BOI • ftMt (211) 95.2 7 MN + fish NMA (2 H) 92 BOH • WP UtI) h6i 32 81 day. OMfoo boan woavll i Offeo MMtt («OB) 16.3 4 XOMt (T) (ItI) 29»? - 72 Ways as + *M*« gM« (M) 37.3 77 day» • T (5t3il) 61.3 36 ty day» ^ M • (5 55^7 firiod tK «kip + Totuit Oil) 73.« 5

Sahlo S Duration of th* iifforwt Iifo »tag» for «opra (CB) and eoffoo boan WMTU (OM).

BS)MI QB OBi ''

«ft 3-5 day. 6-9 4aya bun» 35*46 days 28-36 days Wp* 5-9 day» 8-11 daya A*»lt 49-68 daya 52-108 daya Sable 5« flarviial mt* studies on dlff«r«nt stages and ag«o of oopra beetle irradiated «ith different

of adwlt qa rseowred af fr irraiiatioa. at different aa—V POfAL8TiQI -«Til 1 - 2 d 7-U 5* » 47.2 b 75*5 a ^1.2 cd 76.8 a 88.0 a 49.0 ed 90.2 a 75.8 b 0*01 41.2 be 27.0 d* 57.5 be 38,0 «d 48.2 ed 72.5 a 54.2 be 57.2 C 56.0 e 0.025 16*7 *f 37.2 47*0 ed to.7 ed 77*5 a 54.2 be 44.0 ed 49.8 e 55.5 e 0.05 0 g Os Of Of O f 22.8 • 31.5 ed 3.2 d 5.5 d

0.10 Os 0« Of Of O f 0 f 0.5 0 e 1.5 d

0.25 O g Os Of Of O f 0 f 0 f 0 e 0 e

Mftoaa followed by the SOB» letter «itbln the aa»e stag* are not eignlfieaatly different fraa eaeb other by 9Mf*

the 2 adults obtained lrea 1 replieate «ero already dead opon examination* *NLo 6. *wrlval Mt* stailtt «a *Uf«r*at atagas and ago» of tao aoffto koan «MVU lmdlato* wita TOTIMS

t MM» anui) ai of adult CBt *MOT*M4laftar irradiation at dUCnront a*oaV • •M* t " "JJBi S IBB t LAiT Ab 3 T Aai f Eia£«25UI t 4»5 days old 7-8 d«» Old 1344 days «Ut"?^•wv#' !•>raw-v.g.TT^mr —— O 706.2 a 276*0 «d 383*2 a 374.5 *» 443.8 a 405.5» H 0*025 114*2 b 127.2 o 282*8 e 248.5 edo 261*5» 274*5 b • 0.05 0 e 2.2 g 19*0 f 25.2 f 23*0 e 35.0 e • 0.10 0 e Og Og 14.8 f 2.5 d 4.5 d • 0.25 O e Og Off Off 9 • 0*5*^ •

Monsfollavod by tbo «MO letter within th« son* «tag* of dlff«reat firoa «aoix other by

Adult a werm doad «pan «zaainatloa. Taala 7. l**ov*ry «f Zrradiatad and «ea-irradiatad Balaaaalla jMUritidi^ ia COB* Vlstiag Maila'.

Maaa aiuibar of aturviviac ealla in diff* Abaorfcaat * : Itävin* t t t CkQy) * Xvtriaat t Ioaia t Brilliant : Biaaata t l Agar : Kathylaaa t Gra*n Agar : Sulfita i Bad* Af "• , : : Blua Agar t t Aaar t

11. 13.5x10"

1. 13*5x10 a 1. 12.3x10* 5. 5.3xlO3c 5.OxIO3C 5.3xlO3o 5- 1. 1. l.«xlO2o 1.6x10"

2. 1.8xlO2o 1.7xl02c 1.8xl02c 1.6xlO2

65 o 60 c 50 e 60 c 60 e

65 o 60 c 60 o 50 o 50 e

30 o 30 c 20 e 30 o 30 o

0 e 0 c O e O c O e

0 e 0 e 0 e 0 o 0 o

Haaaa follwad »y *•• aaaa Iat tar ax* a*t eignifioaatly diffaraat wrm ••• «aetli*r ay Duncan'a Multipl* Haag* fast (IMRT). \

V . \ \

/ '3 Tubia S. Orfsnolaptlo ttats on irradiatad and unirradiatad robusta eoffaa*.

Charactariatia t Control a Irr*diat«tf I t o.as MT : 0.50 WT 7.3 7.0 6.8 Flavor 7.0 (!•naral 6.3 7.2 6.7

Data taka» after an «mpubliahtd N.3. Tbasia (Jtabuacado, 1983). •- r

Packaging W/orW/o t Sara i •tart of experiment Mfttefio]^ Food I 1 t 1T I 5 t 10 f SP I 30 i 10 Jut* sack */ 44.5 a 25.9 b 22.2 b 38.9 ab 74.1 a 55.6 b 75*0 m w/o 58.3 a 48.1 a 38.9 a 44,5 a 51.9 b 66.7 a 74.9 a Woven ayntho- tlc PP sack 11.1 O 7.4 e 16.7 b

Adult CB penetrated thru loosed tape»

Table 10» Mean % of adult CBW that penetrated out of packaging material*

JfcoKosine W/orW/O Days Apom startb of experiment Materials Food t 1 t 3 t Ij f t 20 I 30 I 40 Jute sack w/ 11.1 14.3 b 0 b 4.2 be 12.5 b 37.0 a 44.4 a w/o 16.7 b 33.3 a 5«16 a 20.8 a 25.0 a 37.0 a 37.0 a Woven synthetic PP sack •/ 11.1 C 4.7 C 0 b 8.3 b 8.3 O 22.2 b 14.8 b 33.3 a 9.5 be 0 b 8.3 b 16.7 b 29.6 b 14.8 b Hour bag O d 0 d O b O c 0 d 3.7 C 7.4 C w/o - 0 d 0 d 5«,6 a O e 4.2 C 7.4 e 7.4 C PPP w/ 0 d 0 d O b 0 e Od 0 d 0 d w/o 0 d 0 d 0 b 0 o 0 d 0 d 0 d UPP O d 0 d 0 b 0 c 0 d 0 d 0 d w/o 0 d 0 d 0 b 0 c 0 d 0 d 0 d

Means followed by the aov* letter in the sane ooltan are not significantly different from each other by IHIEtT. Tablo U. M«aa % mortality in adult OB at indicated days

Packaging W/orW/O I Dors fro* start of rizaont Food J 1 * 3 I 5 I 10 iI 20 t 30 » 40 Juto saok 0 C 0 o 0 o 0 o 7.4 d 2.6 d 8.3 be %o 11.3 b 5*6 d 6.7 d 8.3 O 11.1 e 0 d 4.2 c '.Vovon syntho- tio PP sack W 0 c 0 o 6,7 d 8.3 C 11.1 C 0 d 16.7 b w/o 0 c U.I C 0 o 16.7 b I4,8bc 11.1 c 4,2 e Hour bag W/ 0 c 0 0 0 o 4.2 d 0 o 2.8 d 12.5 b w/o 0 c 0 o 20,0 c 4.2 d 18,5 b 11.1 o 16.7 b PPP W/ 88.9 a 77.8 b 86.7 b 66,7 a 85.2 a 86.1 a 91.7 a w/o 88.9 a 100.0 a 93.3 a 70.8 a 92,6 a 88.9 a 100*0 a UPP w/ 0 c 5.6 d 0 c 4,2 d 7.4 d 11.1 c 16.7 b w/o 11.1 b 0 e 26,7 c 8.3 C 22.2 b 22.2 b 12,5 b

Table 12. Hoan % mortality in adult CBW at indicatod days

Packaging W/orW/o : Days from start of oxporimont Materials rood < 1 t 3 s 5 » 10 I 20 * 30 I 4<3 Juto sack 0 c 0 d 0 d 0 (i 8.3 od 11.1 e 16.7 e w/o 0 C 5.6 c 5.6 d 4.2 od 12.5 e 8.5 d 4.2 0 Woven Jfcrntli»- tie PP sack w/ 0 C 0 d 0 d e 4.2 d 7.4 d 0 f w/o 11.1 b 11.1 be 11.1 C e!3 C 12.5 e 7.4 d 20.8 e Ilour bag w/ 0 c 0 d 11.1 e 0 d 4.2 d 7.4 d 8.3 do w/o 5.6 b Od U.l e 8.3 e 16.7 O 14.8 e 20.8 PPP w/ 77.8 a 72.2 a 100.0 a 79*2 a «L.2 a 81.3 a b 72.2 a 66.7 a 88,9 a 75.0 a 75.0 b. 85.2 a 95.8 a UPP w/ 5.6 b 22.2 b $•6 d 12.5 b 12.5 e 14.8 e 12.5 d •/o 0 c 16.7 b 16.7 c 16.7 b 16.7 C 22.2 b 20.8 13* ftMNUtlWI MNM % »MU (ft **t f«M*»t«l

Jftte 20.0 a 23.* a 37*2 a 51.1 a fe»4 a 67*8 a •KM O XM k 23*9 k 23.3 k 30*7 k 3%»4 k

O O « 1.1 • 1.1 • 2*2. • 3.3 • 3.3 •

O O « 0« 0« 0« 0« 0«

TOP O O • 0« 0« Ot 0« 0«

Sitt» «Ml tlttt «Nlt

0 O U4i IMi JtMa 40.7«

Um O O M k 9*3 k 12*9 k tf.7 k 20.4 k O O M k M k« 9*9 k* 9*5 • 9*5 • m O O 0« 04 04 04 04 O O 0« 04 04 04 04 •f liv* Mi iMMl Sl p*r pMtaa* of «opr* «t laitaat** af*r irr«tia

&M* If*1r*lW HM «ft (MIr) tftmt*rlaU t f 1 S 2 t 3 i h I 5 i 4 i 9 Ol 2.2 2.0 4.8 1.8 14.8 2.8 2*2 MPf 7.2 2.0 3.5 9.0 1.8 3.5 0 1* 10*v.o0 12*5 2.5 7.2 3.8 2.8 1.8 PPP 2*2 0 0 0 0 0 •oldy

M 1.0 0.5 0 0 0.5 1.6 ; ' Mit 2*2 0 0 0 0 0 0 0*25 Ii 2*5 0 0 0 0*5 0 0 (1*8) (0.8) PPP 0 0 0 0 0 0 •oMjr (1.5) ! OPP . o,5 0*2 0 0 O O (2.2)

Jt O-2 0 0 0 0 0.8 O (1.2) MPf 0 0 0 0 0 • 0*50 JB •.: .0 0 0 0 0 0

PPP 0 0 0 0 0 0 Ml*> VPP 0 0 0 0 0 O •ol*jr (0*2)

OMA «MM •*•%!• IB yrwita—!•«

*Mk| MPP • a*vm ayatMtt* pttyprMgrMMi n m flow bag| FPP «tkrin trmUA p*|rir*igfäta*| VPP •

4*al*i «M •alar 4 MKtfi» firm »•t IUMT Urtl*, «wtMtted kMtl* «Ml alt*». 16* *f liv» M4 •f M«M •t mmXk mtUr

1 BM* ITMlWfIi A -~MJ ILJlIlKJtantttitfta. (Mf) titeMviiOa * JJ 1 1 I 2 I 3 i H t 9 9*8 11.0 12.0 9*8 13.0 11*9 3.9 WW 5.8 ia.o 9*9 11*0 7.8 13*2 2.0 7*2 9*2 U.I 10*8 t.5 1.8 o n 1*5 O O 1*2 O O O wr (2*9) (1*9) (1.2) IW 3*0 2 2*9 0*8 2.9 O O tt) (1.5) Co*5) (0*9) (2*0)

a 1*0 2*9 0*1 10*2« 0*9 O (1.5) WW 1.» 3*9 o*9 104 3*5 2*2 O (3*0) 0.2? IB 1.5 2*0 1*2 0.8 0.9 O O (0.8) WP 0*8 0*9 O O O O O (0.2) (0.5) «HP 1.9 2*0 0*2 O O O O (0*5)

2*2 1*2 O 1.2* 5*8» 0.8 O WW 2*0 0*8 O O O O O 0*90 fi 1*2 1*0 O O O O O (2*2) Wf O O O O O O O (0*2) I» O 0.2 O O O O O ( 0.2)

n m Alt* «Mkl WW iff .NfMWiI tM4 y HTM 0M« aitoa