Radiation decontamination of dry food ingredients and processing aids

Journal of Food Engineering 3 (1984)

245-264

Radiation Decontamination of Dry Food Ingredients and Processing Aids J. Farkas International Facility for Food Irradiation Technology, Wageningen, The Netherlands ABSTRACT Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. i?e procedure is direct, simple, requires no additives and is highly efficient. Its dose requirement is moderate. Radiation doses of 3-10 kGy (0.3-lmrad) have proved sufficient to reduce the viable counts to a satisfactory level. Ionising radiations do not cause any significant rise in temperature. The flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for satisfactory decontamination, and radiation obviates the chemical residue problem. The microflora surviving radiation decontamination of dry ingredients are more susceptible to subsequent antimicrobial treatments. Recontamination can be prevented as the product can be irradiated in its finalpackaging. Irradiation could be carried out in commercial containers and would result in considerable savings of energy and labour as compared to alternative decontamination techniques. It appears that time is on the side of radiation. The demand for dv ingredients of good microbiological quality is ever-increasing and the food industries could well accommodate the cost of irradiation treatment. Radiation processing of these commodities is an established technology in several countries and more clearances on irradiated foods are expected to be granted in the near future.

INTRODUCTION Under the prevailing production food ingredients and processing

and handling conditions, many dry aids, such as spices, condiments,

245 Journal of Food Engineering 0260-8774/84/$03.00 Publishers

Ltd, England,

1984. Printed

in Great Britain

- 0 Elsevier

Applied

Science

246

J. Farkas

texturizing agents, enzyme preparations, etc., contain large numbers of microorganisms capable of causing spoilage, defects in foods or, more rarely, disease. The spoilage and/or health hazards presented by an ingredient must be evaluated always in the context of its use. For food processors contamination of ingredients with heat-resistant bacterial spores is especially troublesome. The destruction of thermoduric bacterial spores introduced to food products with ingredients often necessitates a severe subsequent heat treatment which ensures the microbiological storage stability only at the cost of a substantial reduction in the nutritional and sensory quality of the manufactured product. Such problems account for attempts to reduce the viable cell counts of these ingredients by an appropriate decontamination treatment.

ALTERNATIVE METHODS MICROBIAL CONTAMINATION

FOR REDUCING THE OF DRY INGREDIENTS

Because of the heat sensitivity of the delicate flavour and aroma components of spices and herbs or of the specific functional properties of enzyme preparations or texturizing agents, normal heat sterikation cannot be used. Microwave treatment or ultraviolet irradiation have been tried but are considered unsuitable for decontamination of these dry ingredients (Coretti, 1955; Vajdi and Pereira, 1973). Volatile oils, spice extracts or oleoresins are practically free from microorganisms, but their flavour quality and spicing power generally do not equal those of the original spices: further, solvent residues in the extracts may be of concern. The most widely used method for decontaminating dry ingredients is treatment with ethylene oxide (EO). According to the American Spice Trade Association, in the US alone 800 000 lb ethylene oxide were used in 1977 to treat 80 000000 lb spices (Gerhardt and Ladd Effio, 1982). Even though ethylene oxide is a relatively efficient antimicrobial agent, fumigation is a time-consuming batch procedure and it appears to be beset with problems of uniformity of decontamination and requires a complex process-monitoring (Frohnsdorff, 198 1). The absorbed residual ethylene oxide may remain fairly high after gassing (Kroller, 1966) and although it decreases continuously during subsequent storage of the fumigated product, this is frequently due to further chemical reactions rather than simply to loss of the gas. In addition to

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247

ethylene glycol, ethylene chlorohydrin (ECH) and ethylene bromohydrin (EBH) may be formed during ethylene oxide fumigation (Wesley et al., 1965) and ethylene chlorohydrin is more persistent than ethylene oxide. Although in several countries the maximum permissible level of ECH is 300 ppm, it has frequently been found in ethylene oxidetreated ingredients in concentrations exceeding even the 1000 mg kg-’ level (Stijve et al., 197 1; Gustafsson, 1981; de Boer and Janssen, 1983). Both ethylene oxide and ethylene chlorohydrin are mutagens and they are also suspected of causing other chronic or delayed toxic effects (Ehrenberg and Hussain, 1981; Gerhardt and Ladd Effio, 1982: Kligerman et al., 1983). Ethylene oxide may form toxic 2-hydroxyethylcompounds with lysine and cysteine. Up to 30 ppm of these compounds have been found in dried egg and milk powder (Gerhardt and Ladd Effio, 1982). Thus, EO fumigation represents a significant occupational health hazard for operatives in the fumigation plants and the presence of residues in the treated commodities gives rise to more and more toxicological misgiving, and more and more regulatory restrictions are being introduced (Gerhardt and Ladd Effio, 1982). An alternative physical method for decontamination, therefore, seems highly desirable.

RADIATION DECONTAMINATION OF SPICES DRIED VEGETABLES AND SUGAR Research and development in the past 30 years on a large variety of dry ingredients, herbs and processing aids has proved that treatment with ionising radiation (accelerated electrons, y-rays or X-rays) is a viable process for destroying contaminating organisms. The largest amount of work so far has been devoted to the irradiation of spices and condiments. Depending on the number and type of microorganisms, and the chemical composition of the product, a radiation dose of up to 20 kGy may be required to achieve commercial ‘sterility’ (i.e. a total viable cell count of less than 10 g-i) in natural spices; however, doses of 3-10 kGy can reduce the viable cell counts to an acceptable level (less than lo4 g-l) and this is the dose range which is approximately equal in microbiocidal effect to the commercial fumigation process (Silberstein et al., 19794 b; Farkas, 1983a; Weber, 1983). As an example, a recent study on the microbial population of black pepper clearly shows the efficacy of the radiation treatment (Table 1) (Soedarman

J. Farkas

248

TABLE 1 Microbial Decontamination of Black Pepper by y-Radiation (Soedarman et al., 1983) Microorganism

Log of colony-forming units surviving after 0 kGy

Total aerobic mesophilic Aerobic mesophilic (spores) surviving 1 min at 80°C surviving 20 min at 100°C Anaerobic mesoph. (spores) surviving 1 min at 80°C surviving 20 min at 100°C Enterobacteriaceae Lancefield D streptococci Moulds

et al.,

2 kGy

4 kGy

6 kGy

8 kGy

3.9

2.1

<1.8

1.8

<1.8 _

8.0

6.2

5.2

7.7

6.0

6.6 2.9

4.1 0.2

7.5 5.9 4.7 4.9 4.6

6.1 <2.8 2.8 1.7 <1.8

3.1 <1.8 1.1 0.4 -~

3.0 -

-

<1.8 <1.8 <1.8 <1.8 1.1 <-0.5 <-0.5 <-0.5 _

1OkGy


1983). The germicidal efficiency of irradiation is much less dependent on the moisture content than is that of ethylene oxide (Farkas and Andrassy, 1983a). The surviving microflora of spices treated with a ‘pasteurising’ dose of radiation have lower heat- and salt-resistance and are more demanding as regards pH, moisture and growth temperature requirements than those of untreated spices, which further reduces their ability to survive and outgrow in processed food products (Farkas, 1970; Kiss and Farkas, 1981). The heat-sensitizing effect of irradiation increases with increasing radiation dose and the weakening of the surviving microflora in irradiated dry ingredients is permanent and does not diminish during normal storage of the products. Ethylene oxide is not found to affect the heat resistance of the survivors (Farkas and AndrBssy, 198 1, 1983a, b). No substantial changes were found in the volatile oil content and in the amounts of other chemical constituents of most spices treated with doses up to 10-l 5 kGy (Bachman and Gieszczynska, 1973; Farkas et aE., 1973; Zehnder et al., 1979: Weber, 1983). Although the ‘sterilising doses’ of 15-20 kGy, used during the early experimental period, slightly or noticeably changed the flavour characteristics of some spices

Radiation decontamination

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TABLE 2 Threshold Doses for Organoleptic Changes in Spices and Herbs Product

Caraway Cardamon Charlock Chive Cinnamon Coriander Cumin Curry Fenugreek powder Ginger Juniper Lemon peel Marjoram Nutmeg Onion powder Orange peel Paprika Parsley Pepper (black) Pepper (white) Pimento Thyme Turmeric

Threshold dose, kGy

Reference a

12.5 7.5 10 4-8 >I0 S-10 >lO 8 <5 >45 15 S-10 7.5-I 2.5 >45 8, >9 5-10 15 0.5 12.5 >45 15 10 10

1 1 1

a 1, Bachman and Gieszczynska (1973); (personal communication); 4, Inal et al. (1981); 6, Tjaberg et al. (1972); 7, Zehnder and El-Nawavy (1973); 9, Silberstein et al.

3 297 1,7 2 4 7 6 1 7 1

6 839 7 5 3 1 6 1

7 7

2, Weber (1983); 3, Dirkse (1975); 5, Kiss and Farkas and Ettel (1981b); 8, Farkas (1979b).

(Lerke and Farber, 1960), the 3-10 kGy doses sufficient for ‘pasteurisation’ do not influence the sensory properties of the overwhelming majority of spices (Farkas, 1983a, b; Weber, 1983). The threshold doses required to produce organoleptic changes in spices and herbs are summarized in Table 2. Various meat products prepared with spices which had received doses of up to 20 kGy could not be distinguished by

250

J. Parkas

flavour from products prepared with the corresponding non-irradiated spices (Hansen, 1966; Farkas et al., 1973). Experiments have demonstrated packaging and storage conditions to affect the quality of spices more than radiation treatment (Beczner and Farkas, 1974; Purwanto et al., 1982) and the antioxidant properties of some spices remain unaltered by the radiation decontamination treatment (Kuruppu et al., 1983). The microbiology of dehydrated convenience foods is the microbiology of their ingredients. Radiation decontamination of dehydrated vegetables may therefore offer advantages to dried food processors. In addition to microbial decontamination, a significant reduction in the cooking time of dry vegetables can be achieved at the lo-30 kGy dose range (Farkas et al., 1970). Commercial granulated beet sugar can be sterilised by radiation doses of lo-20 kGy (Sabine, 1956; Kiss et al., 1968) and probably much smaller doses could adequately eliminate thermophilic spores. Canned peas prepared with a brine containing radappertized sugar did not show flat-sour spoilage, in contrast to peas prepared with non-irradiated sucrose. At doses larger than 5 kGy, various degradation products can be detected and discoloration of the solid sugar can be observed. Some of the reaction products have specific microbiological effects (Kiss et al., 1968).

RADIATION

DECONTAMINATION OF TEXTLJRISING AND PROTEIN PREPARATIONS

AGENTS

Some thickening agents (guar gum, carob gum) seem to be more sensitive to radiation treatment than spices and dry vegetables (Zehnder and Ettel, 1981~). In other texturising agents, however, a considerable reduction in microbial contamination can be achieved with relatively small doses, which do not seriously affect the functional properties. French workers were able to show that the viable cell counts of commercial starches could be satisfactorily reduced by doses of around 2.5-3 kGy (Saint-L&be and Berger, 1971; Delattre et al., 1975). Over 4 kGy, changes in viscosity, reducing capacity, pH and iodine-binding capacity occur. In the 10 kGy range, dextrin formation, production of

Radiation decontamination

of dry food ingredients and processing aids

251

glucose and fructose and the Maillard reaction may also take place. At higher doses, technologically interesting new properties could be developed in irradiated starches since their molecular weight, adhesive capacity and water solubility were altered and could be controlled (Rogachov et aE.j 197 1). Radiation sterilisation of pectin in the dry state can be carried out without undue changes. At a dose level of c. 20 kGy, small amounts of dialysable, i.e. small-size? breakdown products are formed and the specific viscosity, corresponding to the molecular size, is reduced by c. 40%. Doses of around 5 kGy, applied in the dry state, do not affect viscosity significantly (Skinner and Kertesz, 1960). Agar is less sensitive to irradiation than other thickening agents (Rogachov et al., 1971). The microbiological quality of gelatine can also be effectively improved without seriously affecting technological or organoleptic properties (Frank and Grtinewald, 1969). Sterilisation of dry gelatine can be achieved at a dose of 35 kGy only at the price of a reduction of gel firmness by a third of the original value. Water solubility and taste are not appreciably affected. Soy flour and protein preparations (whey powder, sodium caseinate, dried blood serum, etc.) may be treated with 5-10 kGy doses which effectively decontaminate them without appreciabIy altering their physicochemical and organoleptical characteristics (Brankova and Dimitrova, 1975; Zehnder and Ettel, 1981a).

RADIATION DECONTAMINATION OF ENZYME PREPARATIONS Doses of around 10 kGy sufficed to reduce the microbial load of fungal polygalacturonase and lipase, and bacterial proteases to negligible levels without appreciably affecting enzyme activity (Vas and Pros& 1965; Diehl, 1982; Hespeels, 1982). Dry papain could be microbiologically decontaminated by radiation doses of 20-30 kGy with practically unchanged enzymic activity (Craeghs, 1980), while ethylene oxide treatment caused approxinlately 80% reduction in both the proteolytic and esterase activity (Pate1 and Gopal, 1979).

252

J. Farkas

STORAGE

STABILITY

OF IRRADIATED

DRY INGREDIENTS

The storage stability of dry ingredients is not impaired by radiation decontamination. On the contrary, it was demonstrated (Farkas, 1973) that radiation decontamination doses prevent mould growth in properlypackaged spices even under high relative humidity, which is an important additional potential benefit particularly for spice-producing developing countries. Because of the much greater radiosensitivity of insects than microorganisms, it goes without saying that radiation treatment for microbiological purposes always ensures insect disinfestation as well, the dose requirement for which does not exceed 1 kGy.

THE ECONOMIC

FEASIBILITY OF RADIATION OF DRY INGREDIENTS

TREATMENT

Like many other physical processing methods for food, irradiation involves relatively high capital costs and the irradiation facility must have a critical minimum capacity for economical operation. However, unlike other processes, irradiation has a low operating cost. The cost of irradiation is, therefore, practically directly proportional to the dose requirement, As in the case of any other food processing technique, the actual costs may be greatly affected by local circumstances. Due to varying conditions, costs for the same type of treatment may differ from place to place and a cost estimate made in one country is not necessarily representative of other countries. However, in view of the several factors outlined below, it is believed that radiation treatment could compete favourably on economic grounds with the alternative decontamination processes: - unlike fumigation, the radiation treatment is easy to automate and to use as a continuous process; ~ radiation can be applied to pre-packaged materials in their final packaging: - the irradiation of such dry ingredients (as distinct from seasonal produce) could be conducted throughout the whole year; - to achieve practical decontamination the dose requirement is moderate:

Radiation decontamination

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- the value of the dry ingredients, herbs and enzyme prep~ations is relatively high, in relation to which the cost of radiation contributes only a small fraction of the cost of the final product; - because of the compactness, high value, stability and transportability of packaged dry ingredients, their irradiation may be effected in centralised facilities and/or on a service basis, e.g. in already-existing irradiation (including pilot) plants; - the demand for decont~inated ingredients is increasing and achieving a better microbiological quality may justify a higher price. The cost of i~adiation of products with a dose requirement of 4-8 kGy is estimated to be of US$O.O6-0.12 kg-l in the existing Dutch irradiation plants (Leemhorst, 1982; Oosterheert, private communication). This is approximately l-8% of the current price of spices. The benefits of using irradiated ingredients, e.g. in the canning and meat processing industry, have been demonstrated by several experiments in which irradiated ingredients resulted in a reduced heat-treatment requirement and/or a better microbiolo~cal quality of the processed foods (Dutova et al., 1970; Farkas, 1973). In addition to its cost-effectiveness, radiation processing consumes less energy than other decontamination techniques (Silberstein et d., 1979a, b; Tr5girdh and Hallstrom, 198 1). It is virtually certain that the regulatory agencies will reduce significantly the tolerance levels for residues of ethylene oxide and its reaction products, and drastically reduce existing limits for exposure to EO for workers in fumigation plants (Anon., 1983~). All these will lead to changes in the operating practices of EO plants, to increasing operating costs and will increase the relative advantages of the radiation alternative.

THE WHOLESOMENESS OF IRRADIATED DRY INGREDIENTS The safety for consumption of irradiated foods has been well established in past decades by very elaborate wholesomeness-testing programmes. The energy taken up by irradiated food is much less than that taken up by heated food. Radiation treatment therefore produces only very small amounts of reaction products and does not leave residues.

254

J. Farkas

Irradiation at the energy levels foreseen (up to 5 MeV for y- and X-rays and up to 10 MeV for electrons) does not induce radioactivity in the foods so treated. Specific animal feeding tests, as well as teratogenicity and genotoxicity studies with various irradiated dry ingredients have been performed, mainly in Hungary, France, The Netherlands and Belgium within the International Food Irradiation Project (IFIP). The results of extensive wholesomeness studies on irradiated foods, including ingredients, were evaluated by an international expert committee (JECFI) jointly convened by the FAO, IAEA and WHO. The JECFI concluded in November 1980 that the irradiation of any food commodity up to an overall average dose of 10 kGy presents no toxic hazard and irradiated foods do not pose specific microbiological and nutritional problems (JECFI, I98 1).

PROCESS CONTROL AND OCCUPATIONAL SAFETY ASPECTS Radiation processing, particularly with y-rays, is a relatively simple technology. Materials to be radiation treated are exposed to a controlled amount of radiation from a radiation source. The food can be treated in packages or it can be treated in bulk. Since irradiation does not induce radioactivity, or heat, products can be handled or shipped as soon as they leave the radiation source. The process of food irradiation may only be carried out in facilities licensed, registered and controlled by the appropriate national authorities. The design of food irradiation facilities is based on actual experience with the irradiation of non-food, viz. the irradiation of medical supplies, electrical insulation, packaging materials, plastics, waste water and sludges. Within the FAO/WHO International Food Standards Programme, the Codex Alimentarius Commission has already established a recommended International Code of Practice for the operation of radiation facilities used for the treatment of foods. Control of the food irradiation process in ail types of facilities involves the use of accepted methods for nleasuring the absorbed radiation dose and monitoring the physical process conditions. Extensive dosimetric calibrations of the irradiator are carried out prior to the commissioning of the plant during processing by routine dosimetry.

Radiation decontamination

of dry food ingredients and processing aids

255

Facility designs attempt to optimise the dose uniformity ratio, to ensure appropriate dose rates and, where necessary, to permit temperature control during irradiation (e.g. for the treatment of frozen food) and also control of the atmosphere. International regulations demand that the radiation sources are operated and stored in such a way that under no circumstances can any radiation hazard arise and workers in a radiation plant must be adequately protected against irradiation at all times. According to current recommendations of the International Commisssion on Radiological Protection (ICRP) the maximum permissible dose for radiation workers (occupational limit) is 5 rem year-’ (50 mSv year-r) and for members of public it is 0.5 rem year-’ (5 mSv year-‘). To comply with these regulations, irradiators usually have a well-separated and shielded area for storage of the radiation source and treatment of the products, which can be entered only when the source is in the safe position or the machine irradiator is switched off. In pilot, semi-industrial and commercial irradiators, concrete is the usual shielding material. Provisions must be made in the shielding design to allow for replenishment of the radionuclide source as it decays, for access to the irradiation zone for maintenance and for normal flow of the irradiated product. The transport route is constructed in such a way that no radiation can reach the entrance or exit. The control system for the irradiation is designed to follow the product’s progression through the irradiation cycle, to control the conveyor operation, to control the gamma source position and shielding, and to prevent and control fires. To preclude the possibility of operator exposure to radiation, interlock systems are required. Standard practice calls for double interlock systems (mechanical and electrical) to ensure that the operator is not jeopardised due to failure of a protective device. An electronic system controls the sequence of operation and all control functions are displayed on a control panel. There is a positive indication of the correct operational and safe positions of the source which is interlocked with the product movement system. A safety interlock system is integrated in the control and radiation monitoring system and causes the gamma source to be lowered into the storage position by gravity immediately if there is a fault in the normal operation. A radiation monitoring system guards all locations where radiation could leave the radiation shield. The air in the irradiation chamber is

256

J. Farkaf

constantly changed by forced ventilation to remove ozone produced in the air by the ionising radiation. Experience has shown that there need be no measurable addition to the existing (natural) background radiation, i.e. the workers and neighbours at or near such facilities receive no more radiation from the radiation processing facilities than they do from anything else in the same general area (there is background radiation everywhere, including within the bodies of human beings). In most countries the radiation level outside the irradiation chamber must not exceed 0.25 mrem h-i (2.5 @v 11’~‘). Workers in a food irradiation plant could thus receive a maximum annual dose (50 weeks, 40 h per week) of 500 mrem, i.e. a dose equal to the maximum permissible dose to the public. In reality, they receive much less. (It is worthwhile noting in this context that from all natural sources we are exposed to approximately 130 mrem radiation year-‘; in an aeroplane at 10 000 m and above the dose rate is 0.5-l mrem h-‘; and a yearly average radiation dose from watching colour television 3 h day-’ is estimated to be approximately 6 mrem.) According to risk estimates based on the determination of alkyl groups in haemoglobin in persons occupationally exposed to ethylene oxide at the respiration rate of light work, an E-0 exposure dose of 1 ppm h-l results in a tissue dose estimated to involve a risk amounting to 10 mrem equivalents (Calleman et aE., 1978: Latarjet et al., 1982). The reliability of the y-irradiation system is illustrated by the fact that, for example, the radiation plants in The Netherlands operate without attendants overnight and at weekends. It has also been found that guards, gates, fences, frightening warning signs, etc., are not necessary for the safe operation of radiation facilities.

THE LEGISLATIVE STATUS OF RADIATION TREATMENT OF DRY INGREDIENTS Legislative recognition of the safety of irradiated foods lags somewhat behind the achievements at the UN level. As regards irradiated dry ingredients, dried fruits and vegetables, etc., various clearances have already been issued in Belgium, Bulgaria, Canada, Chile, France, Hungary, The Netherlands, Norway, USA and USSR (Table 3). Growing interest is shown by the fact that further petitions for clearances on irradiated

Radiation decontamination

of dry food ingredients and processing aids

257

spices have also been submitted or prepared recently in Brazil, Canada, the Federal Republic of Germany, Israel, Spain and Sweden. Petitions are also pending: on papain, dried blood serum, gelatine and tea in Belgium; on gum arabic, dried blood serum, dehydrated vegetables and cereal flakes in France; and on dried vegetables (onions, leeks, garlic, horseradish, celery-root, carrots and mushroom) in the Federal Republic of Germany with a maximum dose of 10 kGy. The Food and Drug Administration (FDA) of the US published, early in 1981, i.e. before the publication of the Proceedings 1980 JECFI, an ‘Advance notice of proposed rulemaking for irradiated food’ (FDA, 1981). This document stated among other things that the FDA is considering ‘permitting irradiation of any food at a dose not exceeding 100 krad [ 1 kGy] ‘, and ‘adoption of a policy that a food class comprising only a minor proportion of a daily diet and irradiated at a dose of 5 Mrad [ 50 kGy] or less may be considered safe for human consumption based upon minimal biological testing’. The labelling of irradiated food is a controversial issue. While most countries which have issued some kind of regulations on food irradiation require that foods processed by radiation and packaged for retail sale should bear prominently a phrase such as ‘treated by ionising radiation’ or ‘treated with ionising energy’, opinions differ widely on labelling of ingredients and second generation products containing irradiated ingredients. More and more authorities, however, accept the view that an irradiation labelling statement is not required on nonirradiated foods that contain irradiated minor ingredients such as spices (Anon., 1983b). For example, according to suggestions of the Canadian Bureau of Consumer Affairs, foods containing an ingredient treated with ionising radiation would not require an indication in the list of ingredients that the ingredient has been so treated unless the total mass of such ingredients constitutes more than 15% of the total mass of the product (Anon., 1983~). Declaration of an irradiated food product on the accompanying bills of lading and invoices for international trade is a universal requirement. It is worthwhile to note in this context that labelling statements are not required for processes such as methylbromide or ethylene oxide treatment. In order to aid harmonisation of national legislation and to facilitate international trade in irradiated food, the FAO/WHO Codex Alimentarius Commission has already adopted an International General Standard for

Disinfestation

Unlimited

+

+ +

f +

+ + +

Radiation source ‘Vs Electron

W-0

and Processing Aids

Spices

Mixed spices (black pepper, cumin, paprika, dried garlic; for use in sausages) Mixed ingredients for canned bashed meat (wheat flour, Nacaseinate, onion and garlic powder, paprika)

Hungary

Experimental batches

Experimental batches

Decontamination 5

Unlimited

De~on~mination

Decontamination

s

11 (max)

+

+

+

Acceptance of all foods which were the subject of evaluation by the I980 JE’CFI

France

Chile

0.75 (max)

Flour, whole wheat

Canada

flOW

Experimental batches Experimental batches

Disinfestation Disinfestation

1 1

Dry food concentrates Dried fruits

Bulgaria _-

Provisionat Provisional

Belgium

Decontamination Decontamination

Provisional Provisional Provisional

Category

10 (max) 10 (max)

Purpose

Decontamination Decontamination Decontamination

kGy

Dose,

10 (max) 10 (max) 7 (max)

Product

Paprika Black pepper Gum arabic Spices and aromatic substances (78 commodities) Dried vegetables

Country

TABLE 3 Worldwide Status of Clearances Granted on Dry Food Ingredients

1983 1983

20 November 1976

2 April 1974

1983

1982

25 February 1969

30 April 1972 30 April 1912

September September

10 November 1980 10 November 1980 September 1983

Date of clearance

USSR

USA

Dried fruits

South Africa

mush,

(38 commodities)

seasonings

Spices and dry vcgetablc

Wheat tlour

gruel rice pudding)

(buckwheat

Dry food conccntratcs

Spices

Dried bananas

Norway

10 (max)

0.2-0.5

0.7

1

0.5 fmax)

10 (max)

Decontamination

Disinfcstation

Disinfcstation

Dishtfcstation

Disinf~station

Decontamination

Unlimjtcd

Unlimited

Unlimited

Unlimited

batches

+

+

+

+

+

f

~~p~rirn~n~l

5 MeV

4 April

1974

1966

5 July 1983

1963,1964,1966

6 June 1966

15 February

1983

1983

1983

28 July 1977

25 August

25 August

1983

1980

1979

1978

8 February

15 March

13 March

1971 1974

26 June 1975

4 October

4 October

13 September

1982

3 MeV

4 MeV

+

acceptance

Unlimited

Temporary

Decontamination Decontamination

7 (max) 10 (IhaX)

Dried vegetables

Dry blood proteins

acceptance

Temporary

Radicidation

6 (max)

Temporary

Decontamination

10 (max)

Malt

I;gg powder

acceptance

Temporary

D~~on~mination

10 (mas)

Spices

acceptance

acceptance acceptance

Temporary Tempomry

Disinfestation

t

Decontamination

IO (max)

spices

Ground

rice products

acceptance

Temporary

acceptance

Test marketing

Decontamination Decontamination

Experimental Temporary

Decontamination Decontamination

Spices

4 MeV

1983

1981

Unlimited

blltchcs

f +

27 October

Test marketing

Decontamination

+ + + + + + + + + + +

Test marketing

Decontamination

I.5

8-10 IO fmax)

~-

5 5

10 (max)

batter mix

Spices

Netherlands

Powdered

Spices and condiments

The

Spices

Spices for sausages

J. Farkas

260

Irradiated Foods. The findings and conclusions of the 1980 JECFI have been incorporated into a revision of the general standard. The FAO/ WHO Codex Committee on Processed Meat and Poultry Products is evaluating irradiation as an alternative treatment for spices to be used in meat products.

COMMERCIALISATION OF RADIATION DRY INGREDIENTS

TREATMENT

OF

As can be seen from the above-described developments, irradiation of dry ingredients is now an emerging technology in several industrialised countries and increasing amounts are treated commercially in Belgium, Holland, France, Norway and the US. Several years ago Novo Industri A/S in Denmark installed a 6oCo plant to irradiate powdered enzyme preparations. Radiation treatment of spices has particular importance for those developing countries where the export of spices is a valuable contribution to convertible currency earnings. Research and development programmes have been launched in recent years in Chile, China, Egypt, Ghana, Indonesia, Malaysia, Nigeria, Peru, Philippines, Sri Lanka, Thailand, Turkey and Zaire on irradiation of spices (Farkas, 1982). Worldwide commercialization of the process will depend greatly on general international acceptance of the recommendations of the 1980 Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food and/or the International General Standard for Irradiated Foods and the Recommended International Code of Practice for the Operation of Radiation Facilities for the Treatment of Foods as recommended to national public health authorities by the Codex Alimentarius Commission of the Joint FAO/WHO Food Standards Programme.

REFERENCES Anon. (1983~). NIOSH recommends

lowering air exposure standard for ethylene oxide. Food Chemical News. 1 August, 56, Anon. (19836). Irradiation labeling. Food Chemical News, 19 August, 1. Anon. (1983~). Canada proposes treating food irradiation as a process. Food Chemical News. 19 August, I i- 15

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