Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. se oe t = A _ ; ee _ge . - - 7 - 5 ’ 4 i ; - ia J ar 2 a = —- co a - od UY ria: = 7 = sas — he, = “ . s t= é = a = -s& . ¥ bon i ‘ . 7 = { io ' 1 ‘ » ry . : . . + ” ? ' a tad + oF ~ fi . - ~ F \ ise wr. - i - J i iy é - . 7 . ‘ . ‘ ‘ ? un a Q 7 . e - . - 4 Py ® > * n i + . 7 ’ = i ua é ‘ S i fi . | - Z o ry i ; : ; baht & sad OD RADIATION-PASTEURIZING —— FRESH STRAWBERRIES ~ 38 AND OTHER FRESH FRUITS 7a AND VEGETABLES: Estimates of Costs and Benefits ‘ PREPARED BY U.S. DEPARTMENT OF AGRICULTURE/ECONOMIC RESEARCH SERVICE WASHINGTON, D.C. 20250 FOR U.S. ATOMIC ENERGY COMMISSION /DIVISION OF ISOTOPES DEVELOPMENT ERS-225 TID 21628/ISOTOPES-INDUSTRIAL TECHNOLOGY/TID 4500 (19th Ed.) Prepared for the Division of Isotopes Development of the United States Atomic Energy Commission by the Marketing Economics Division, United States Department of Agriculture, under contract No. At (49-11)=2085, LEGAL NOTICE This report was prepared as an account of Government=-sponsored work. Neither the United States, nor the Atomic Energy Commission, nor any person acting on behalf of the Commission: ao Makes any warranty or representation, expressed or implied, with respect to the accuracy, completeness, or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or process disclosed inthis report may not infringe privately owned rights; or b. Assumes any liability with respect to the use of, or for damages resulting from the use of any information, apparatus, method, or process disclosed in this report. As used in the above, “‘person acting on behalf of the Commission’’ includes any employee or contractor of the Commission, or employee of such contractor, to the extent that such employee or contractor prepares, disseminates, or provides access to, any information pursuant to his employment or contract with the Commission, or his employment with such contractor, Printed in U.S.A. Price $2,00, Available from the Clearinghouse for Federal Sci- entific and Technical Information, National Bureau of Standards, U.S. Department of Commerce, Springfield, Virginia 22151 Saka PREFACE This report on the economic feasibility of pasteurizing selected fresh produce commodities by ionizing radiation is based on research conducted for the Division of Isotopes Development, U.S. Atomic Energy Commission. It compares preliminary estimates of radiation-pasteurizing costs with estimates of some important benefits which may result from this new method of food preservation, Included also isa brief discussion of the potential impact of radiation-pasteurizing on produce market structure, conduct, and performance, Dr. Robert H, Reed, of the Western Research Office of the Marketing Economics Division, ERS, participated in planning the research and gave valuable assistance in the analysis. Dr. Kevin G Shea and Mr. George R. Dietz, Division of Isotopes Development, U.S. Atomic Energy Commission, assisted with technical information and helpful suggestions. The author appreciates the technical information and suggestions received from a number of persons representing these public and private organizations: Brookhaven National Laboratories, Upton, N. Y. Atomic Energy of Canada, Ltd., Ottawa, Canada. U.S. Army Natick Laboratories, Natick, Mass. Vitro Engineering Company, New York, N. Yo Associated Nucleonics, Inc., Garden City, N. Y. Ethicon Corporation, Somerville, N, J. High Voltage Engineering Corporation, Burlington, Mass, Radiation Dynamics, Inc., Westbury, N. Y. General Electric Research Laboratory, Schenectady, N. Y; and Vallecitos Atomic Laboratory, Pleasanton, Calif. University of California, Davis. University of Florida, Gainesville. University of Michigan, Ann Arbor, Continental Can Company, Chicago, Il. Hazelton Laboratories, Inc., Falls Church, Va. U.S. Department of the Interior, Bureau of Commercial Fisheries, Washington, D.C. U.S. Department of Commerce, National Bureau of Standards and Office of Technical Services, Washington, D.C. U.S. Department of Agriculture, Agricultural Research Service, Washington, D.C. Federal Power Commission, Washington, D.C. - ili - CONTENTS Page SUMMiariye o “ote lewlertel stStye cakolweL RS ‘ojllew lolol tetiok cule: os Molia. ontotloljoo somo? oglomtodlolne Introduction. «© © © » @ © 6 6.0 6, se 6 Me “0.6, 6/04 0° 6" 0: © 010,10) sl wohbomo st @oMmodte domteiae The Economic Importance of Recent Spoilage Losses in Marketing ... © o o « Radiation Sources; and: Facilities is sertctts: le. leila fate Ber aplod of oleentclMoitelier ch clhckis) ole Cobalt 60 << dextentettettecates cb Stat etoticike tot euiel cio ov oaor otta ter oil ote Bokiome toll cine toate XeRay Machinesi.13 2 olstse © ove e eo 6160 et ene Gis: (6, 6 oe ier oe ton onier siteitentcie Facility Output <. 6 2 « © © 6 © 6+ o 0 l0:),0GoMio! 0; eto oucltoltomocl comodo cet: ctMol foktoMels Radiation- Pasteurization Cost Estimates 4 6 112e.10c20r0000e0 000080068 ASSUMPLIONS « «0 6 i 5 © 6 © 0 © 0) 70t labs iocouiobs, of silo Col Mol Guobe godasotis Nokolicoten Cost Components » « « © 6 © © 6.0 wl on. sks Gel oWotle, o\ciketic lowe ballot eMouslomctcmts Variable Costs. « & 5 oe © © son of% i's © ComMel teste! owls, soll loliohic holko kealdcikslGeets Fixed Costs 2+ 6.6 © 0 © © © 6.6 © © © ©» 10) 40/16, toAlel Wontos¥otler oil oktomo cad Mel oklom@omie Average Total. Costs co:eeats oxo taetlaicl's,jotlietle tomes ovo Pol lol felis helto oMcbmolkol %e Kole Benefits Expected from Radiation-Pasteurizing Fresh Strawberries and Other Produce ¥ sive ie; 3 ole chee Srierte tion eleeGs Copivite tops Aa Gop lol “clroscitoio mihotients Spoilage Loss Reduction » 6 6 © 6 0 © © » © « @ ojtenio.',o cello eio kolo toh calomcMieme Reduced Need for Chemical Spoilage Inhibitors .adévestl oSeiketel Shor oe Yello Tol wits Implications of Radiation- Pasteurization for Fresh Produce Markets ...... 15 Bibliography . o « © © © 6 6 010. © 06 © oiuo, tomletob ckloAo goituaioakiohion kes Nomkslrein onto at Appendix . o so s © 6 6 6 © » © & 6 © 0 © oyhslo, Gch femelle? o, veRloGomicine meied ofits mC nICmmED OdDONIAInNIrtonP PRNE ae i oe Wr March 1965 - iv = SUMMARY Radiation-pasteurizing of strawberries would reduce spoilage loss by at least enough to pay the cost of treatment, according to preliminary estimates of costs. Additional savings might be realized because (1) the shelf life would be increased, (2) less in-store culling would be necessary, and (3) use of carbon dioxide gas as a mold inhibitor could be reduced oreliminated. For California strawberries shipped to New York City, the present cost of the carbon dioxide treatment is about 0.3 cent per pound. Considerable potential exists for reduction of spoilage loss of fresh peaches, tomatoes, oranges, and grapefruit, but more technical research information is required before estimates of economic feasibility of radiation-pasteurization can be made, The U.S. retail value of recent spoilage losses of these commodities is 0.2 cent to 4.9 cents per pound of shipping weight. Tomatoes are at the top of this range. Technical research at the University of California, Davis, reveals that if fresh strawberries are radiation-pasteurized by an optimum dose of 200 kilorads it is possible to hold spoilage losses during marketing to about 5 percent, depending on amount of infection with spoilage organisms at harvest. Accordingly, estimates of spoilage loss savings, on the basis of the recent U.S. retail price of 45.2 cents per pound, would range from 4.3 to 4.5 cents per pound shipped to market, depending on the extent to which the practice was adopted by the strawberry industry. Savings in this range are substantially more than enough to pay for estimated radiation- pasteurizing costs. Estimated radiation-pasteurizing costs for an applied dosage of 220 kilorads by selected facility type, size, and hours of annual operation are: Bae H ae: : : Cost per pound roreconed : Nope : He aes 22,000 hrs. +: 4,000 hrs. c yP : : s (half year) : (full-year) Cobalte60 tee. ss she 2 Lekwe or 68,000 curies $167 5287 2.9 cents 2.0 cents Colatl GriG Os ca.5. es, 0.00 4.0 : 3 kw. or 204,000 curies 316,862 <7 " oe a 3-Mev. X-ray machine.: 3 kw. 522,000 2.4 " LG " These cost estimates are based on a 2-shift operation, 5 days per week. Cobalt 60 and X-ray machine facilities are assumed to have 30 and 35 percent net utilization efficiencies, respectively, and source use factors of 95 and 80 percent, respectively. In this analysis, the radiation-pasteurizing cost estimates for cobalt 60 facilities declined when the facility size was increased from 1 kilowatt to 3 kilowatts or when the hours of annual operation were increased from 2,000 to 4,000 for either facility size. For the 3-kilowatt X-ray machine, this increase inthe length of operating season decreased the cost per pound by one-third. Accordingly, facility size and the expected hours of annual operation should be considered as major economic factors when investing in food irradiators, It should be emphasized that radiation capacity can be enlarged by replicating small irradiators as well as by installing larger ones. The adoption of radiation-pasteurization by the strawberry industry would represent a significant increase in the barriers to entry of new shipping firms be- cause of the investment requirements. Consequently, one would expect shippers to -V- increase in size and decrease in number, perhaps accompanied by some increase in market power of the surviving firms. Fruit and vegetable handling and marketing methods would not be expected to change significantly as a result of radiation-pasteurization. However, because of increased shelf-life more time would be available for orderly marketing. This is especially important for highly perishable produce commodities. = Vil = RADIATION-PASTEURIZING FRESH STRAWBERRIES AND OTHER FRESH FRUITS AND VEGETABLES: ESTIMATES OF COSTS AND BENEFITS By John H, Droge, Agricultural Economist Marketing Economics Division Economic Research Service INTRODUCTION Spoilage losses in marketing fresh produce are substantial despite dramatic improvements in handling practices, containerization, and use of chemical decay deterrents. Results of technical research now in progress indicate that low-dose radiation-pasteurizing holds real promise for some commodities as a method of reducing spoilage and increasing shelf-life while retaining fresh product qualities, Ly No pilot produce-irradiating facilities have been constructed, and no market tests have been made for radiation-pasteurized produce, But technical research involving the use of small-scale irradiators has advanced to where it is possible to make meaningful preliminary estimates of radiation=pasteurizing costs. In the study reported here, specific objectives were (1) the development of preliminary cost estimates for radiation-pasteurization of fresh strawberries; (2) estimation of money values of some important benefits expected to result from radiation-pasteurization of fresh strawberries; (3) development of preliminary estimates of the economic feasibility of radiation-pasteurizationoffresh strawberries; and (4) an evaluation of the likely impact of this new method of food preservation on the structure of produce markets and methods of marketing. Attention was centered on the economic feasibility of radiation-pasteurizing fresh strawberries because for the other products considered--peaches, tomatoes, oranges, and grapefruit--technical feasibility studies of radiation-pasteurization were still in progress and the results were not available, Recent technological developments have outdated published information on costs of food irradiation from ionizing energy. For this reason, much of the technological and cost information used in this study was obtained by informal discussions with engineers, food technologists, and other specialists directly concerned with food irradiation research and development. (See preface for list of organizations re- presented.) This is the second report on the economic feasibility of radiation-pasteurizing of fresh strawberries, peaches, tomatoes, oranges, and grapefruit. An earlier T7 Radiation-pasteurizing should present no health hazard, In February 1963, the Food and Drug Administration cleared radiation-sterilized bacon in its first irradiated-food petition, Sterilization requires a much higher dosage than pas- teurization, Food additive petitions need to be submitted for any use of radiation in either sterilization or pasteurization of foods if such use is not covered by specific regulations. The only petition filed for radiation-pasteurizing fresh fruits or veg-= etables was for oranges and lemons (Federal Register, Dec. 18, 1963). Additional data are being sought before action is taken onthis petition, Next fall, the Atomic Energy Commission plans to file a petition for radiation-pasteurizing strawberries. report summarized results of an opinion survey of 306 fresh produce shippers, wholesalers, and retailers (5). 2/ THE ECONOMIC IMPORTANCE OF RECENT SPOILAGE LOSSES IN MARKETING Three sets of estimates of spoilage losses incurred in marketing the five com- modities studied are given intable 1. Since the estimates were made from information obtained in different time periods and from different sample designs, the differences among them are to be expected. Those in column two, of average percentage losses in 1957-61, are the basis of the calculations inthis analysis. They represent a relatively recent period, and conform rather closely to the informed opinions of chainstore produce managers obtained in the 1962 survey reported inthe earlier study. If the upper limit for potential savings from radiation=-pasteurization of fresh commodities is defined as the value of the average loss from spoilage incurred in marketing the commodities, potential savings in marketing fresh strawberries may be estimated at $17.8 million a year. This is the average annual spoilage loss for 1959=63 shown in table 2. The potential savings in marketing the other commodities studied are also presented in table 2, as well as data on farm production both for the fresh market and for processing. Appendix table 10 shows, by State of origin, the 1962 domestic interstate shipment of each commodity for the fresh market. For California, which ships more than 50 percent of the Nation’s fresh strawberries, production of strawberries for the fresh market is reported by month, county, and shipping station in appendix table ll. Table 1.--Estimates of marketing spoilage losses, United States, 1942-51, 1957-61, and 1962 1942-51 spoilage : 1957-61 spoilage : 1962 spoilage as a Fresh : f : ee coeds losses as a percentage : losses as a percentage spercentage of quantity ees ; of quantity shipped 1/ : of retail value 2 : shipped 3 esa oe antes Sas aoa eee ae eee Percent=—=====-=—==- eee eee Strawberries..: A ed. PEO 130 Peaches sss f 56 9.0 8.4 TOMabLOeS «46 bes 8 21.6 16.0 9.7 Orangesés ds «0's 15.3 Irs 3.8 Grapefruit....:3 4/ 2.4 3.8 dh Losses in Agriculture. A Preliminary Appraisal for Review (15). 2/ Includes total spoilage requiring items to be discarded, and partial spoilage re- quiring reduction in retail prices. Unpublished estimates of the Market Quality Research Division, Agricultural Research Service, U.S. Department of Agriculture. 3/ Opinions of independent and cooperative chainstore produce managers. Number of observations from each city are: Boston 5, Chicago 4, and New York 4. 4/ Not available. 2/ Underscored numbers in parentheses refer to Bibliography, De 20. re Table 2.--Farm production and marketing spoilage losses, selected fresh fruits and vegetables, United States, annual averages, 1959-63 : : : : Fresh marketing spoil- ; Eoeaenreoue on i Fresh marketing : age losses valued at Commodity Sree hae pence aauarelere spoilage losses 1/ : 1959-63 U.S. retail : : : : prices 2/ : (1) : (2) : (3) : (4) : 1,000 units 1,000 units 1,000 units Million dollars Strawberries....: 262,990 lb. 229,424 lb. 39,449 lb. 17.8 Peaches 3/......: 4/33,894 bu. 4/36,791 bu. 3,051 bu. 26.2 TOMA TOSS: «0-06-00 $ 1,003 tons 4,287 tons 160 tons 97.3 Oranges 5/....--: 6/42,813 boxes 6/84,040 boxes 685 boxes 8.4 Grapefruit 7/...: 6/24,046 boxes 6/18,411 boxes 577 boxes 5.4 1/ Estimated by multiplying quantities in col. 1 of this table by spoilage loss percentage estimates in table 1, col. 2. 2/ Computed by multiplying retail price per pound (appendix table 14, col. 4) by physical spoil- age losses (col. 3, this table). 3/ 1 bushel equals 50 pounds. 4/ Farm sales. 5/ Assuming 70 percent are 90-pound boxes and 30 percent are 75-pound boxes. 6/ Annual average production for 1959-61. 7/ Assuming 90 percent are, 80-pound boxes and 10 percent are 66-pound boxes. Source: Agricultural Statistics 1963 (17). RADIATION SOURCES AND FACILITIES Among the different types of available ionizing radiations, gamma rays and X-rays appear to be well suited for food irradiation, Also, accelerated electrons can be used directly for food irradiation if the pene- tration required is of a relatively shallow depth. 3/; However, they are not included in this analysis because not enough information is currently =e nie on application techniques and other technical relationships. Cobalt 60 Cobalt 60 is included as a radiation source inthis study because it appears to be the least costly source of gamma rays. The other nucleide radiation sources considered were cesium 137 and zirconium-niobium, Cobalt 60 is produced by the irradiation of cobalt in nuclear reactors. For each kilowatt of radiation=source capacity, 68,000 curies are required. It is assumed that this radioactive material will be assembled in many replaceable segments to facilitate source replenishment, X-Ray Machines Linear accelerators have the greatest potential among the electron machines for X-ray production because they have higher energy electron-beam ratings than the other machines, and because they can be built in larger kilowatt sizes (table 3). Linear accelerators as well as the other electron machines produce accelerated electrons which can be converted to X-rays by means of a suitable target. Table 3.--Present and estimated future performance characteristics of electron machines 1964 wenines Present Estimated future 5 performance é performance : Kw. Mev. Kw. Mev Van de Graaff generatore.ceccccccccssece’s 1-5 1-4 No significant change Resonant transformer. x. .resrovscke: siec0.0 2 eee 5-10 1-2 25 BS a Ria ail eam ae Weseanuaael ae 15-30 1:3 1/70 335 Linear accelerator...... areletorereVeucislevereroieievele 1=10 3-10 250 3-10 Insulating core enaieromicy, (ICT). seeeee » Ondo 0. 3=0.5 20-30 HS OAT ets : 1/60 3.0 ly Being developed for both electron and X-ray production. Sources: Preservation of Food by Low-Dose Ionizing Energy (14) and information from the High Voltage Engineering Corporation and Radiation Dynamics, Inc. 7 o7 The depth of electron beam penetrability expressed interms of unit density is generally recognized to be 1 centimeter/2 Mev. (million electron volts). - 4 - The penetrability of X-rays produced from 3=Mev. accelerated electrons is almost identical to that of gamma rays produced from cobalt 60. Therefore, in this study we consider 3-Mev. X-rays and gamma rays from cobalt 60 to be equally effective for use in food irradiation, For a given target, the conversion efficiency of accelerated electrons to X-rays depends on the electron kinetic energy expressed in Mev. For tungsten, these calculated forward X-ray production efficiencies apply (9): Forward X-ray production Electron kinetic energy efficiency Mev. Percent alles e@eeeoeeo0e15u83e eee e eeee eeeoe eee 230) Pe @eeesoseov<¢ee8e? e eooee eee eeoceesteee eee ee A et SNe Pate hate ele ee ole ete ae hee Ue te Cero Pa 6.2 lay ade dal Mavetaane, oxcteta el creratne Soehate'« Se grate erate, LAEIO OWN eteners heteta orale evel crete atte Gucle S's lnialeelelaverence 18.7 These data show that X-ray production efficiency can be improved by increasing the energy of the accelerated electrons from which the X-rays are produced. Facility Output The potential volume of produce that can be radiation-pasteurized by a radiation facility is directly related to these factors: 1, The size of the radiation source. The facility sizes considered inthis study are, for cobalt 60, 1 and 3 kilowatts, and for X-ray machine, 3 kilowatts. 2. The radiation dose. As referred to inthis discussion, applied radiation is the radiation striking the surface of a package being irradiated, as distinguished from radiation absorbed by it. Absorbed radiation dosage varies by location in the 3- dimensional space of an irradiated package. The acceptable rule-of-thumb for computing absorbed dosage variation within an irradiated product is represented by the minimum to maximum ratio 1:1.25, Technical research on radiation=pasteurization of fresh strawberries indicates that (1) 175 kilorads are required as a minimum absorbed radiation dosage for good results, (2) 200 kilorads are optimum, and (3) 225 kilorads are a permissible maxi- mum, According to the 1:1.25 rulesof-thumb, an absorbed dosage of 218.75 kilorads is needed to assure that the minimum of 175 kilorads will be met (175 kilorads multiplied by 1.25 = 218.75 kilorads), Therefore, an application dosage level of 220 kilorads is considered inthis study. 3, The net utilization efficiency of the radiation source, This refers to the percentage of total radiation emanation absorbed by the material being irradiated. The net utilization efficiency of an ionizing radiation source is the product of (a) the percentage of area efficiency, and (b) the percentage of thickness efficiency of absorption, In this analysis, the area efficiency of irradiation refers to the dis- tribution or dispersion of ionizing energy inthe form of gamma rays or X-rays over the product surface area. Similarly, the thickness efficiency of absorption refers to the percentage of ionizing energy absorbed through the third dimension of the product. This can be significantly influenced by the geometry (physical location) of the source in relation to the package to be irradiated, the thickness of the package, and the specific gravity of the product contained in it. = 5 = 4, Nonuse time. Experience indicates that electron machines generally require considerable downtime for maintenance. This should be considered when appraising the relative advantages of cobalt 60 and X-ray machines as sources of radiation, In this study, the cobalt 60 facilities areassumed to have a use factor of 95 percent and the X-ray machine facilities to have a use factor of 80 percent. 4/ Table 4 shows the number of pounds of food that can be irradiated per hour per kilowatt of radiation source capacity at selected dosage levels and net source uti- lization efficiencies. Hourly facility output can be computed from the data inthis table by using the number of kilowatts of facility capacity as an expansion factor. For example, assume a 3-kilowatt cobalt 60 facility, an applied dosage level of 220 kilorads and a 30=percent net source utilization efficiency, and proceed as follows: (1) Enter table 4 to find the relevant output for 1 kilowatt of operation per hour, which is 1,120 pounds; (2) reduce this poundage 5 percent, to 1,064 pounds, to adjust for estimated nonuse time during facility operating periods; and (3) multiply 1,064 by the expansion factor 3 to obtain the answer, which is 3,192 pounds of facility output per hour. Accordingly, the g@utput would be 6,384,000 pounds for 2,000 hours of annual operation, Table 4.--Number of pounds of food that can be treated per hour per kilowatt of ra- diation facility capacity by selected dosage level and net utilization efficiency Net. utilization efficiency : ECS ae gadis eoinnels : 200 : 220 : 240 $ --------------------+- Pound's===—~=-— = =S-22sss—— Bite ein aoe Sf Re as ga ma 2,000 1,867 1,734 AV Eater Mescpave eset a ete avexb) ore:.0' 6) oko fe) 056/ee eereonesene 1,800 1,681 1,460 Le ee eet te Soe tee ee 1,600 1,494 1,387 SD aie. o ereveteler sie eves Glorocaisieienerece a aisvererens 1,400 15,307 dl lypsp2a ISS Bor esreee! REE AL SUOGRG DOME : 1,200 1,120 1,040 ZL Die sexe: eee g slionerejole ecenene bib ere ehele evexe ‘ 1,000 934 867 2. Oisia; Stare 6 6 ie.6y 50 te ey ehete vere: eyee ohexstenete shane: eepore 800 747 694 Source: The Handbook of High Voltage Electron-Beam Processing (7). 4/ Boehm (3) cites experience by one firm in sterilizing medical sutures and other products with electrons from Van de Graaff accelerators, These machines had occasional breakdowns, and operated 70 to 80 percent of the time. This firm has also operated linear accelerators for several years, Other estimates of downtime range from 10 to over 30 percent, depending onthe electron machine considered. Because no industrial experience base has been established for the 3=Mev., 60-kilowatt insulating core transformer (ICT-3000), it is assumed for this analysis that it would be out of service for maintenance 15 percent of the time. This seems to be consistent with a facility use factor of about 80 percent, because additional time would be required for maintaining ancillary equipment, RADIATION=PASTEURIZATION COST ESTIMATES Assumptions In an analysis of plant organization and costs, numerous assumptions are in-~ volved, particularly in studies of new processes. Actual plants operate in a complex organizational setting, conditioned by technical and institutional constraints, For this reason, assumptions and simplifications are necessary to prevent the analysis from bogging down in details. The major assumptions and specifications on which this analysis is based are as follows: 1, Facility engineering and design costs will be spread over several units, and therefore, are not included in this study as a separatecost item. An indication of the magnitude of these costs is given in appendix table 12. 2. Radiation-pasteurizing facilities will be located at existing fruit and vegetable packinghouses or assembly points, No major changes inthe basic layout and design of existing packinghouses need be made. The radiation-pasteurizing facilities will be added to them; their costs will be added costs, (In actual practice, efficient use of radiation-pasteurizing facilities may require some consolidation of existing packinghouses and assembly points.) 3, The purchaser owns the required investment funds. Operating (or working) capital will be borrowed at a cost of 6 percent, simple interest. 4. The net source utilization efficiency for radiation=pasteurization of the specified fruits and vegetables is 30 percent for cobalt 60 and 35 percent for the 3=-Meyv. X-ray machine, 5. As stated in the discussion of the nonuse time (p. 6), cobalt 60 facilities are assumed to have a use factor of 95 percent and X=ray machines a use factor of 80 percent. Cost Components The cost components to be evaluated on an annual basis are (1) variable costs, (2) fixed costs, (3) total costs, and (4) average total costs per pound of facility output. Variable Costs Variable costs include expenses for labor, source replenishment for cobalt 60, power=-source replacement such as tubes and other parts for X-ray machines, electric power to operate conveyors and other ancillary equipment, electric power for X-ray machines, variable office and administrative expense, variable expenses for maintenance and repairs, and other expenses directly related to the volume of output. Total variable costs by hours of annual operation for selected sizes of cobalt 60 and X-ray machine facilities are shown in table 5, They were calculated by applying specific cost rates to the estimated quantities of the variable services required, The specific cost ratesandinput quantities used also are shown, and esti- mates of average variable costs per kilowatt hour of annual facility operation are given, Pe, ee Table 5.--Estimated annual variable costs for cobalt 60 and X-ray machine facilities, by hours of annual operation and size of facility, 1964 - 2,000 hours (half year : 4,000 hours (full year Item B Cobalt 60 3, X-ray machine : Cobalt 60 :X-ray machine : l-kw. 3: 3-kw. 3 ~kw. alkyl si Bakwees 3-kw. 1. Labor expense: 1/ : 2 technicians at $6,000 annual salary: 6.0 6.0 6.0 12.0 12.0 12.0 1 electronic engineer at $12,000 an- : nual salary..... shevsiehaxeienerelers sie owiehe oe ba = 6.0 =o: == 12.0 2. Source replenishment at 14 percent for : Cobalt 602) Masse ee é B cropenecele case One 18.5 cies 6.2 18.5 ae 3. Power-source seni deenenes such as tubes ; and other parts for X-ray machine Sek os -- -- 12.0 =- — 24.0 4, Electric power for conveyor and an- 3 cillary equipment 4/...... suaietete sievajare a sfaee Ose 0.3 0.3 0.4 0.6 0.6 5. Power inputs for X-ray machines 5/ Dees vote : -- -- 2a — — 54 6. Variable office and administrative : expense (overhedd )) dsrcps als oieSd eres: 0 e1ets orsje : 6.0 6.0 7.0 12.0 250 14.0 7. Variable maintenance-and repairs : (largely conveyor and ancillary elec- : tronic equipment) <.oc.1d eteteepecte solves ne a OLO 5.0 4.0 8.0 10.0 8.0 8. Other expenses Gskccra aerated to the ; volume of output, including cost of : PUGL. (aNd: WATCH s se.0.c0 sole sews sisteververcesres: “Oe3 0.4 0.4 0.6 0.8 0.8 9. Allowance for contingencies 6/.......-.:_1.5 3.0 4.0 3.0 6.0 8.0 Total ‘variable: COSTS. \t.sreieccerseisielersersy eres 39.2 42.4 42.2 59.9 84.8 $ ------------------------ Dollars------------------------..-- j 10. Average variable cost per kw.-hr. of : annual facility operation..... siotetooiapasRelL oc) 6.53 7.07 10.55 4.99 7.07 i/ Assuming 2 shifts, 5 days per week. Greater use of labor for maintenance was anticipated for X-ray machine facilities than for cobalt 60 facilities (see assumption 5, p. 7) because of the difference in use factors of these facilities. vy | 9,520 curies x 65 cents. Determined on the basis of 68,000 curies per kilowatt of facility size, and a replenishment price estimated at 50 cents per curie plus 15 cents per curie for-encapsulation and transportation. 3/ Estimated at $6 per hour for a 3-Mev. insulating core transformer, ICT 3000. L/ Determined from present commercial electricity rates for California, Florida, Louisiana,and Michigan published by the Federal Power Commission. 5] Determined from present industrial electricity rates for California, Florida, Louisiana, and Michigan published by the Federal Power Commission. 6/ Funds to pay for unpredictable cost items including those associated with downtime. Source: Estimates by the author based on: (1) research experience with cobalt 60 irradiators in the United States and several foreign countries as explained by Otto A. Kuhl, L. E. Kukacka, and B. Manowitz, Brookhaven National Laboratory, July 13, 1964; (2) research and commercial experience with electron and X-ray machines revealed by representatives of the organizations listed in the preface, and from the | published sources listed in the. bibliography. Fixed Costs Fixed costs include allowances for depreciation, interest on facility investment, taxes, insurance, and fixed repairs and maintenance each estimated as a percentage of investment cost, Fixed costs also include salaries of management and supere visory personnel, interest on short-term loans that may be required to pay current operating expenses, and other expenses of ownership that cannot be avoided by closing down operations. Investment costs for the different types and sizes of radiation facilities con- sidered are based on estimates of current replacement value of equipment and other durable instruments of production, These include the cost of source and equip- ment and of transporting them to plant site, and installation costs including the cost of installing ancillary equipment. Investment costs for selected sizes of cobalt 60 and X-ray machine facilities are shown in tables 6 and 7, respectively. Total fixed costs, and the basis for their calculation, are shown intable 8, The table also gives average fixed costs per kilowatt hour of annual facility operation, Average Total Costs The average total cost is the sum ofthe average variable and average fixed costs, To find the average total cost per pound for treating fresh strawberries with cobalt 60 in a facility of 1 kilowatt capacity, the following steps are required: l, Find in table 4 the quantity=-1,120 pounds--that can be treated in an hour under the assumptions used in the foregoing analysis (an application dosage level of 220 kilorads and net source utilization efficiency of 30 percent.) 2. Multiply this quantity by 95 percent, the facility use factor for cobalt 60 (page 6), to obtain 1,064 pounds as the average output per hour. 3. In tables 5 and 6, find the average variable and fixed costs per hour of oper- ation, For an annual operation of 2,000 hours, these costs are $12.10 and $18.95, respectively, Add these two figures and divide the total of $31.05 by 1,064 pounds (average output, from item 2 above) to obtain an average total cost of 2.9 cents per pound. (See table 9 for comparable figures for different facility sizes and annual hours of operation, ) A similar procedure is required to compute average total cost estimates for X-ray machine facilities, In this analysis, a net source utilization efficiency of 35 percent and a use factor of 80 percent are applied to X-ray machine facilities. For a 3-kilowatt or 204,000-curie cobalt 60 facility operated 2,000 hours annually at the 220 kilorad dosage level, the estimated average total cost is 1.7 cents per pound (table 9), The comparable estimate for a 3-kilowatt 3-Mev. X-ray machine facility is 2.4 cents per pound. For 4,000 hours of annual operation, the estimate is 11 cents per pound for a 204,000-curie cobalt 60 facility and 1.6 cents per pound for the comparable 3=kilowatt 3-Mev. X=ray machine facility. The corresponding engineering and design average cost estimates shown in table 12 should be added to these estimates if it is contemplated that only one facility will be installed by a manufacturer. ah ile Table 6.--Estimated investment cost components and total capital investment require- ments for two selected size of cobalt 60 radiation processing facilities, 1964 : Facility size ees ; Tok. 3a. : Curies Curies Facility requirements 1/.......0..062 T3020 232 , 560 : Dollars Dollars Cost per curie: Q/R th eee BAR POE 0.50 0.50 PNCApSWMA TIONS ese tis area's ste Ss ete oS 0.10 0.10 Cost per facility: : Source plus encapsulation......... 46,512 139, 536 Transportation at 1 cent per curie: i) ry ee eeeee ate jee stecehonevene a. O16 775 2 326 Installation costs including : building and ancillary equipment : COSUSWL | tisiaers.saraaeiaawa Sentences 120,000 175,000 Total facility investment..... 167 ,287 316,862 shy Based on information supplied by Vitro Engineering Company. An allowance of 14 percent for self-absorption energy loss and for sufficient over-design to assure rated capacity at the end of source replenishment periods is included. ra In September 1963, the U.S. Atomic Energy Commission established a selling price of 50 cents per curie for cobalt 60 with a specific activity of 30 curies per gram or less when in lots of 100,900 curies. Both the 1l-kw. and 3-kw. facility sizes considered in this analysis use substantially more than 100,000 curies of cobalt 60 when replen- ishment requirements are included for a designated depreciation period of 8 years. Accordingly, the purchase contracts are set at a base price of 50 cents per curie in this analysis and they are assumed to include initial source loadings (item 1) plus yearly replenishment requirements (item 2, table 5) to be delivered during the depreciation period. The seller is to assume ownership of all used source materials removed from a facility. 3) For an average shipment of 1,000 miles. 4/ Facility engineering and design costs are assumed to have been spread over several units, and therefore are not considered to be a cost item. Source: Same as for table 5. - 10 = Table 7.--Estimated capital investment requirements for a 3 Mev., 3-kw. X-ray machine facility, 1964 : Facility investment 1 Item : Per kilowatt $ Total : Dollars Dollars 1. Purchase price of 3-Mev. X-ray machine......: 6,000 360,000 Zn transportation costs to, plant Sites... csecset 33 2,000 3. Installation costs, including building and :; anciiiary equipment 2) averen estes eee ee ose ees : 2,667 160,000 Total facility investment...ccceccccsevscee’ 22,000 1/ Investment cost estimates are based on the 3 Mev., 60-kw. insulating core trans- former, ICT-3000 electron machine. ef The cost estimate includes $40,000 for building construction. Facility engineer- ing and design costs are assumed to have been spread over several units and therefore are not considered as a separate cost item. Rather, they are assumed to be a part of the purchase price of the facility. Source: Estimates are from High Voltage Engineering Corporation, Burlington, Mass.; $40,000 was added to their estimate of installation costs to cover building construc- tion. The radiation-pasteurizing cost estimates for cobalt 60 facilities declined in this analysis when the facility size was increased from 1 kilowatt to 3 kilowatts or when the hours of annual operation were increased from 2,000 to 4,000. For the 3-kilowatt X-ray machine, this increase in the length of operating season decreased the cost per pound by one-third, Accordingly, facility size and the expected hours of annual operation should be considered as major economic factors when investing in food irradiators, To realize 4,000 hours of annual operation of a facility onthe basis of 2 shifts a day 5 days a week would require irradiation of one or more commodities in addi- tion to strawberries, Recent technical research at the University of California, Davis, shows that fresh vine-ripe tomatoes can be radiation-pasteurized with good results. Information on prospects for irradiation of tomatoes and the other com- modities studied is summarized in appendix table 13. Using the 3-kilowatt facilities and an applied dosage level of 220 kilorads, 3,192 pounds of produce can be irradiated per hour with cobalt 60, and 3,138 pounds with an X-ray machine. Expressed in terms of 12-pint cartons of strawberries, this is 319 cartons with cobalt 60 and 314 cartons withthe X-ray machine. Hence, about 4 1/2 hours would be required to irradiate a 1,400 carton carload of strawberries. Of course, radiation capacity can be enlarged by replicating small irradiators as well as by installing larger ones. BENEFITS EXPECTED FROM RADIATION-PASTEURIZING FRESH STRAWBERRIES AND OTHER PRODUCE The physical requirements for handling fresh fruits and vegetables are not changed significantly by their radiation=-pasteurization, Therefore, present-day market handling methods would be adequate for irradiated produce. Table 8.--Estimated fixed costs of cobalt 60 and X-ray machine facilities, by selected hours of annual operation and size, 1964 2,000 hours 3 4,000 hours F Cobalt 60 : X-r ray machine Cobalt 60 : X-ray machine Item dokwes mae 3-kw. : 1-kw.: 3-kw.: 3-kw. ‘f= 2s eee eee 1,000 dollars----------------~----- 1. Depreciation, 8-year straight-line rate based on total facility investment.......: 20.9 39.6 65.2 20.9 39.6 65.2 2. Interest on total facility investment at : 6 percent 1/ sialeielorcieiee Bisel! stale\erereTalerelsieiaxe oer 10.0. 19.0 31.3 10.0 19.0 Sl 3. Real estate taxes and facility insurance : 2) sptosiserae sitggrajepchera Senin biateme eiaepo stem seeinainaterss » ala Sara Sag EY, Ber Sue. 4, Fixed eee and maintenance, and other : unavoidable expenses of ownership........: 0.5 0.6 0.6 0.5 0.6 0.6 5. Salaries of management and Aeeenrilcory, Personnel: B/ii wdaisehs «3 Aoshi, cei’ < bE taser 20 5.0 5.0 820re 10.0 10.0 6. Interest on short-term loans at 6 neacenes 0.8 10 tad 1.6 2.0 3.0 Total fixed Costs ss cscsseles cs ces rpacouets 3769 OGL 108.8 42.7 74.4 115°3 ea ee ee ee Dollars-----=--==—-=-=-~~-_====---~- 7. Average fixed cost per kw.-hr. of annual : FACTIATY OPELALION s: SOOT CWO, | Zeon -- -- 6 TZ6 ocr 7 == Sao =5 a5 a as soeeeeess UOT SUTYS eM fon Oz a = Sa 9T 4 Fe ae pars nam =a aa pias syebsravere ete rend shore sees Ua) ret gOLssS == =e ie ae 99€ ogs*€ = z9d*T oo z= a == = see eeeeuTToreg Yyynog ' 61 7 Aake roves Ax ae ee are we een Sa Se PEs $e Soaceis gis. e-e19/ 88! TI OROAG NG =a = — -- -- On Ti -- -- -- -- or cece RUT TOLeD UZLON ¢ = pas aN € pn ee, a as es rs ae pean eceoeeereee °° *UeSTYOTH HSOSE ale 7s meas pa Hy 259 LZus2 99 a = pat a ©) rere sere e-ereie sie8 OA TOOD) 9S95T == rates _— ZZ ESEST 8ST -- -- -- -- -- == ae ee Sars eS? 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UPS = Otd =e aot —— == == oe 89L €Lt OnT T -- “= pe esecsecteeesoeenesees omrQyEUy *asuesQ , 9$2°T BE S9 ot 88 9S SET hSe2 8619S 8 pe me 7S pritstteeerersesereeeespurteg ‘fo19eqUoy CL i aaa i So a => T OL Z == a = pees eeeeeeeseegapasuy SOT ‘saTesuy soy Gr — = a ou 2s Se aE onl G ee == = ichntsonianammitnnereegaate ‘ousatg Se a a a a ee SDE OTC ree en aaa Sena TeyoL | toed * aon * +400 * +ydeg * -any > «tmp? oump > dey * sady ‘rem 5 sqoq > suep - uotyeys pue £yuNo0D Z96T SsuzUuoW pue SsuCTz.eys SseT4yUNOS sq squswdtus AtZoqmerj{s ysSety %:eTULOFTTEO--*TL eTqeL Table 12.--Facility engineering and design: Average cost estimates per pound of output, 1964 1/ nei Rn Remar q Cobalt 60 : X-ray machine P : 1-kw. facility 2 3ekw. facility : 3-kw. facility $0 wee ee eee ee Cenits=—=—— === $= SS ce Sue DOO OMMOUNS Scie ele rersieieleie Sie se ois 0.43 Oi6 0.16 PHAOO Ops OUteSiacetelerey exe siereeetelatelere s\ O22 0.08 0.08 ay Assuming only 1 facility is built. The estimates include 8-year straight-line depreciation plus 6 percent return to the purchaser on the initial engineering and design costs. The estimated engineering and design costs by facility Size are (1) 1-kw.--$50,000; and (2) 3- “kw. --$55,000. Table 13.--Post-harvest life span of selected fresh produce in retail stores, and in cold storage with and without radiation-pasteurization : Maximum extension : Probable max- sere : ‘ Commercial cold : of life span in : imum doses for Presha;.. Displayc~an retail ys Mee commode Sroreuil, : storage ware- : cold storage after: acceptability ; = $ house 2/ : radiation pasteur-: of product : : : ization : 5 H Days Days Days Kilorads Strawberries. : 12 7-10 4/Double 225 Grapefruit...: 4.5 30-45 NA Se Orangesscec cas 45 35-85 Bf 30 200 Peaches: Wnrapes scree iis 15-30 4/Double 200 Ralpelsaiaiee ecc1s ES aS 3/4 days = Tomatoes: : Mature f SLCC s ciere sus == 15-45 NA = Rape store cient 2-3 8-10 3/4-8 days 300-400 1/ Maintaining Produce Quality in Retail Stores (10). 2/ The Commercial Storage of Fruits, Vegetables and Florist and Nursery Stocks (23). 3/ Maxie, E. C. and Sommer, N. F. Radiation Technology in Conjunction with Post- Harvest Procedures as a Means of Extending the Shelf Life of Fruits and Vegetables. In Summaries of Fourth Annual Atomic Energy Commission Food Irradiation Contractors Meet- ing, Oct. 21-22, 1965, CONF 641002, in process of publication by Div. of Isotopes Devipmt. and Dar: Biol. and Med., U.S. Atomic Energy Comn., Washington, D.C. 4/ Radiation-Preservation of Selected Fruits and Vegetables G2 Die «= 2le U.S. Department of Agriculture POSTAGE ANDFEES PAID Washington, D.C. 20250 U.S. Department of Agriculture OFFICIAL BUSINESS Table 14.--Monthly average retail prices received per pound for selected fresh produce commodities, 1959-63 : Market city oy S Porno Commodity ¢ Boston Chilcago (s- iNew) Yorks (i: au “h) age =! : (1) : (2) : (3) : hike {aaa ee ee Cents per pound------------------ Strawberries 2] Sree ie 56.0 49.7 52.8 45.2 Peaches? 3 + sic etsuerseiorsisisitietenre tae eR OMMIOHO 18.5 17.0 LAE2 TOMA TOSS Hits ans oot hohe olerodote te everere s ANG B3N3 3847 30.9 30.4 Oranges, size Nos 200 4/acie.v.. 29 W383 14.9 14.8 14.3 Grapefruit, size No. 64 5/......: 12.7 11.8 12.8 ‘PO uy The U.S. average represents 20 major cities including Boston, Chicago, and New York. 2) Average of prices for April, May, and June. 1 pound of strawberries is 1 1/3 pints. 3/ Average of prices for July, August, and September. 4/ 1 dozen oranges, size No. 200, weigh 5.44 pounds. 5/ 1 grapefruit, size No. 64, weighs 1.2 pounds. Source: Bureau of Labor Statistics monthly and annual reports.