D:34 499 •ÖcS~—jpence of Ethylene oxide Sterilisation Parameters on hygienic Quality of ^<>®ixtures ------------------------------------------ -------- 31 ------ ■* ---- SiR nik ) ^ °8a Portoroz, Yugoslavia k?looRlem 0f spice contamination, specially in food industry, where it can cause econo- Ojfte a?68-0?’’ 1?ss Possit>ly health hasards, is well resolved by the means of Ethylene 3lic , erilisation. On the other hand, the problem of residues may be important to the vr^ion Particulary when unadequate fumigation conditions are applied. By my M „7» the question of parameters is of the basic significance to the residual degree, ik ae me decdde to determine the optimal fumigation conditions. data *i^WpXturesV regardin® from the microbiological point of view, may be the cause of food 8oiian<? “ in extreme cases the cause of infections. Spices are initially contaminated W^tatd microorganisms like spore forming aerobs and facultative anaerobs. Further con- ¿ S t i ? 1 takes Place during harvesting, fermentation, drying and transportation. The con- j/Srit may also take place during spice mixtures production. The determination of dif- licablPeS °f micr?oreanisms maynot be applicable to the other spices and may be poorly ■ ®5icp 6 pd® spices of the same consignement. The most common groups of microorganisms ‘*>6 8 are moulds, yeasts and bacterials genera Bacillaceae and Enterobacteriaceae. ^!vcsteer 0f a-erol:>ic Bacteria has no direct relation with public health risk, but may a spoilage risk of the product in which a spices are used (10). Total bacterial fyftm Q fOW V»in/ir*a/ia -i n V\niT 1Amr/vn a U414 __—X. __J _! ______ j .1 ■ ¡5 ^ilvles from a few hundreds in bay lesves, chili, mustard, cinnam on and clo . 1*imai°?8 in black Pepper, paprika, cumin, coriander etc. Aerobic spore number is ’ 16 hundred times smaller comparing with total plate count (5,9, 11,12, 13, 14. 1?» 18, 19, 20, 21, 22, 23, 24). ’ ’ cloves to is V^la C 40 a?aa® are present in an average number of a few ten thousands in majority of spices. V toW ? te ■ species is Bacillus cereus, present in approximately 30 % of samples. MKcU 6 flaCeae are also commonly present in spices in levels from a few tens to a few „ N ( c 3* Salmonella does not appears usually, Proteus sp. and Escherichia coli appears 15’ 16> 25’ 26, 2 7. 28, 29). act also as antioxidative and antibactericidal agents due to their active com- V^hce ^ etheral oils, glucosids, aldehids, kethons and kinons. Therefore, the spices *5 “acteT, s . reduction of their own microflora and the reduction of the product microflora. *5, 34) ldal activity is noticed mostly in cloves, cinnamon, garlic and unions’(30,. 31, Ü diffars l°r instance in black pepper from a few to a few millions per gram, ^ thoua r?m S ^6W hundreds to a few ten thousands per gram and in ginger from none to “sands per gram. The dominate species are Aspergillus and Pénicillium (5, 6 , 7, 8 , jiq Æ KaûiSma Present in spices have not the ideal conditions for multiplication and Vhen a®aia* 1 S°, the spices themselves do not represent a direct health hasard, but Hh0 orB:anfaded to the product, where the conditions are much more favorable. Herein, the ^°liaiSmS 5ul®kly reach the exponental degree of multiplication. In this way their K pf?ducts (gas, acid) may demage the product, or in the case of toxin formation Catl0n °f pathogens they may be of a great health hasard risk. Hoy,VUif® the spoilage and the infection possibility, sterilisation of spices is nowa- f *1 i&^thoric,8^ aÜ ever the world. Fumigation, as one of the most common used sterilisa- u® has the advantage in its effectiveness on spices micriflora and disadvantages Nr^ion o Pr°2®s®lngs ^ Potential health hasards of residues. Epoxides employed in Prar^f® ox^de and the asymmetric Propylene oxide. The epoxide molecula ûh.^ ca 7.7 wl^ structures, cutting off the cells methabolism, multipli- 0 Senetic system, what results the bacterial death ( 12 , 35 , 36 , 37 , 38 ). ) 5 ^ailj’ ePoxddf reacts with spice structures physicaly by sorption (diffusion, iV^lein adsorption) and chemicaly, forming Ethylene glicol and Ethylene halohydrins. f1 .ethylene glicol formation is not of the same importance as the one of Ethv- tk ®4 in?- whlch LD<50 is approximately hundred times higher (38). There are also'' vi., 6 ?? dps mutagenicy (35)- The question of residual carcinogenity is V 4« ment still undisolved ( 35 ). Tem ^88 fumi 8 ationi there are some factors that influence .the effect of sterili- da T>n +-V1r *0 OTTO o n « ! /, ____ x. _• - . , . . . P4ay® a ¿ouble role. First, it influences the vegetation of spore for- 4 ? microorganisms. The effect of Ethylene oxide on spores is neglecting in com- ^ On xne eiiecr 01 Htny _ ___ __ _J, ______ __________ ____ e^ ec* on vegetative forms of bacteria (39). Secondly, the higher appli- Veroe8('iTSUio s®adler necessary applied parameters (concentration and exposure) Nk c°hnp x- 57’•58’ 40-)* The concentration and exposure of Ethylene oxide is in a 8iou7tl0n ^lth ei'fe9t on present microorganisms of spices (23, 39, 40). The dif- Ps of microorganisms differ in sensitivity to Ethylene oxide activity what
Transcript
D:34499
•ÖcS~—jpence of Ethylene oxide Sterilisation Parameters on hygienic Quality of ^ < > ® i x t u r e s ------------------------------------------ -------- 31------ ■*----
SiRn i k) °8a Portoroz, Yugoslavia
k? looRlem 0f spice contamination, specially in food industry, where it can cause econo- Ojfte a?68-0?’’ 1?ss Possit>ly health hasards, is well resolved by the means of Ethylene 3lic , erilisation. On the other hand, the problem of residues may be important to the vr ion Particulary when unadequate fumigation conditions are applied. By myM „7» the question of parameters is of the basic significance to the residual degree, ik ae me decdde to determine the optimal fumigation conditions.data
*i^WpXtures V regardin® from the microbiological point of view, may be the cause of food 8oiian<? “ in extreme cases the cause of infections. Spices are initially contaminated W tatd microorganisms like spore forming aerobs and facultative anaerobs. Further con- ¿Sti?1 takes Place during harvesting, fermentation, drying and transportation. The con- j/Srit may also take place during spice mixtures production. The determination of dif- licablPeS °f micr?oreanisms maynot be applicable to the other spices and may be poorly ■ ®5icp 6 pd® spices of the same consignement. The most common groups of microorganisms ‘*>6 8 are moulds, yeasts and bacterials genera Bacillaceae and Enterobacteriaceae.!vcsteer 0f a-erol:>ic Bacteria has no direct relation with public health risk, but maya spoilage risk of the product in which a spices are used (10). Total bacterialf yftm Q f OW V»in/ir*a/ia -i n V\niT 1 Amr/vn aU4 1 4 __— X.__J _!______ j .1 ■
¡5^ilvles from a few hundreds in bay lesves, chili, mustard, cinnam on and clo
. 1*imai°?8 in black Pepper, paprika, cumin, coriander etc. Aerobic spore number is’ 16 hundred times smaller comparing with total plate count (5,9, 11,12, 13, 14.1?» 18, 19, 20, 21, 22, 23, 24). ’ ’
cloves to isV^laC 40a?aa® are present in an average number of a few ten thousands in majority of spices. V toW ? te ■ species is Bacillus cereus, present in approximately 30 % of samples.M K c U 6flaCeae are also commonly present in spices in levels from a few tens to a few „ N(c3* Salmonella does not appears usually, Proteus sp. and Escherichia coli appears 15’ 16> 25’ 26, 2 7. 28, 29).
act also as antioxidative and antibactericidal agents due to their active com- V ^ h c e ^ etheral oils, glucosids, aldehids, kethons and kinons. Therefore, the spices *5 “acteT, s . reduction of their own microflora and the reduction of the product microflora.
*5, 34) ldal activity is noticed mostly in cloves, cinnamon, garlic and unions’(30,. 31,
Ü diffars l°r instance in black pepper from a few to a few millions per gram, thoua r?m S ^6W hundreds to a few ten thousands per gram and in ginger from none to “sands per gram. The dominate species are Aspergillus and Pénicillium (5, 6 , 7, 8 ,j iqÆ KaûiSma Present in spices have not the ideal conditions for multiplication and Vhen a®aia* 1S°, the spices themselves do not represent a direct health hasard, but Hh0orB:anfaded to the product, where the conditions are much more favorable. Herein, the ^°liaiSmS 5ul®kly reach the exponental degree of multiplication. In this way their K pf?ducts (gas, acid) may demage the product, or in the case of toxin formationCatl0n °f pathogens they may be of a great health hasard risk.
Hoy, VUif® the spoilage and the infection possibility, sterilisation of spices is nowa- f*1 i& thoric,8 aÜ ever the world. Fumigation, as one of the most common used sterilisa- u® has the advantage in its effectiveness on spices micriflora and disadvantages Nr^ion o Pr°2®s®lngs ^ Potential health hasards of residues. Epoxides employed in Prar f® ox de and the asymmetric Propylene oxide. The epoxide moleculaûh . ca7 . 7 wl structures, cutting off the cells methabolism, multipli-0 Senetic system, what results the bacterial death (1 2 , 3 5 , 3 6 ,3 7 ,3 8 ).
) 5 ^ailj’ ePoxddf reacts with spice structures physicaly by sorption (diffusion,iV^lein adsorption) and chemicaly, forming Ethylene glicol and Ethylene halohydrins. f1 .ethylene glicol formation is not of the same importance as the one of Ethv- tk®4 in?- whlch LD<50 is approximately hundred times higher (38). There are also''vi., 6 ?? dps mutagenicy (35)- The question of residual carcinogenity isV 4« ment still undisolved (3 5 ).Tem 8 8 fumi8 ationi there are some factors that influence .the effect of sterili-
d a T > n + - V1 r * 0 O T T O o n « ! / , ____ x. _• - . , . . .P4ay® a ¿ouble role. First, it influences the vegetation of spore for- 4 ? microorganisms. The effect of Ethylene oxide on spores is neglecting in com-^ On xne eiiecr 01 Htny_ ___ ___J,________________ ____e ec* on vegetative forms of bacteria (39). Secondly, the higher appli- Veroe8('iTSUio s®adler necessary applied parameters (concentration and exposure)Nk c°hnp x- 57’ •58’ 40-)* The concentration and exposure of Ethylene oxide is in a 8iou7tl0n lth ei'fe9t on present microorganisms of spices (23, 39, 40). The dif- Ps of microorganisms differ in sensitivity to Ethylene oxide activity what
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influences the survival degree of different microorganisms. Bacillaceae are the most ?e~i tant to the Ethylene oxid in comparison with Coliforms for instance, where the necessary 'Oj applied parameters must be much more severe when the same effect is to be obtained (40)• action of Ethylene oxide depends a great deal on Water content of spices, which acts as M solution and transfer media. 14- % moist spices for instance ties app. 50 % higher quanti' ties of present epoxide compared with totaly dried spices (4). The rule of atmosphere ®e' ^ lative humidity and relative humidity in the chamber during fumigation is not quite cle®?Ji (5i Some authors (57) consider them to have a little influence in the fumigation process, w®) ».the others (7) consider the influence to be significant. The water content of majority oI spices is satisfactory high to obtain the full effect, only few are not. The moistening would result the improvements but later significant increase of microorganisms would > noticed due to stimulating role of increased water content. Multiplication and toxin sy®' si thesis ability of microorganisms depends in a great deal on water activity. The minim®!, 14 aw values for moulds for instance are between 0,62 and 0 ,9 5 , for yeasts between 0,62 ah® G 0,92, for Enterobacteriaceae between 0,95 and 0,96 and for Clostridium between 0,97 and 0,98 (41). The aw values of spices are much below the minimal necessary aw values of ®A" ,rity of microorganisms what results the unability of present microorganisms to multiply ¡,eand to form toxins. Further on, the cell mambrane looses its permeability what results Hipowered employed parameters to obtaine the satisfying effect (59). The storage of fumiS9 'lospices does not influence the microbiological quality when the proper storage conditi°®fi.6, ; are applied. The influence of packing and largeness of units is also of a great imports® \*b The packing materials, common used in distribution of spices and spice mixtures usually, do not suite the fumigation because of their unpermeability. The penetration of gas is proportion with thickness of plastic used as packing material. The best packing media \ fumigation purposes is jute for granulated spices and natron paper for grained spices 4 45). The difussion of gas into the spices depends of largeness of spice seeds respecti ' the degree of graining and of largeness of units. The bigger the unit is, the longer is necessary for gas to reach the center of the bag, and the prolonged fumigation is ®ee full.Due to Ethylene oxide activity, temperature, vacuum and ventilation conditions, there proceed some chemical and organoléptica! changes. The content of etheral oil for insta®® depreciates, simultaneoussly the reduction of active components is remarked, what in£W enees the lessening of spice activities (25). Organoleptical changes, when applied pa®9' meters are not exagerated, are not significant with an exeption of mustard (1 2 ).Ethvlene oxide residues immediately after fumigation are relatively high (a few hundred® ppm) but show the expotential tendency of falling. Two to three weeks afterwards they 1® to zero respectively to a few ppm what suits the regulations if they exist, but may eV (ji represent the health hasard risk (5, 22, 56, 42, 45, 44, 45). There is an open questionother residues like Ethylene halohydrins which quantity increase compared with EthyleIie oxide reduction (11, 25, 58, 44, 45, 46, 47).
Materials and Methods
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Source_o£ sampleAll spice mixtures were produced, fumigated and analysed in HP Droga Portoroz, Yugosia in 1 9 8 0 .PackingSpice mixtures were packed into 50 kg natron bags.Fumi£ati£n_methodFumigation took place in two Degesch chambers (6,9 m ) under producers instructions (l)‘ Fumi£ation_m£di_a_T-gas, consisting of 90 % of Ethylene oxide and 10 % of Carbon dioxide.Mi£r£b ological- a4 a.lZ.ses_Samples were analysed for Total plate count, aerobic spore count, moulds, coagulasa positive Staphylococcus, Salmonellae, suifid. reductive Clostridia, spore forming sul* 1 reductive Clostridia, Proteus sp. and Escherichia coli.Microbiological analyses were done according to Yugoslavs Standards (2, 5)« Micr£biolpgi£al mediaAll media were purchased from TORLAC Beograd, Yugoslavia except Malonat-Phenylalani® broth, which was purchased by DIFCO, Detroit, USA
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Dejtermination of esi duesEthylene oxide residues were determined by El Kishen method (4).
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and discusióny i 'v positive Staphylococcus, Salmonellae, suifid reductive Clostridia, sporei Sulfid reductive Clostridia, Proteus sp. and Escherichia coli were not present' examinated conditions of fumigation.r- on totji* ¡$1 dependingf
«ct on total plate count (I), aerobic spore count (II) and moulds number (III) depending on applied parameters. (I) of spice mixtures, fumigated 5 to 6 hourst0urB \ „^4-v, /inn tr W r „4- o o o n . ( *
K -
) with 400 g of EO/nr at 220C (31°C), failed approximately for two powers and 5* the app. values of a few ten thousands per gram. (II) and (III) showed the simi- sm0 ect with final contamination degree of app. a few hundreds per gram. Drasticaly , :;s. °€ed fumigation did not influence the essential improovement of effectiveness.g of E0/m3 for 17 to 18 hours at 23°C resulted the best effectiveness. (I) fal- JI) for three powers reaching the level of thousand bacterias per gram and even less.
, (HI) were absent (less than hundred per gram). All the tested temperatures, > Uhl8°G’ 20°5> 21°C, 22°C, 23°C, 25°C, 31°C and 34°C) and durations (55, 5 - &h, 7 - 1* (/*V h’ ^ ~ and 51-k) showed a similar effects. (I) varried from a few thousands to W) thousands with an average value of a few ten thousands bacterias per gram.'lt)4 (HI) varried from less than hundred up to a few thousands per gram. Prolonga- temperature increasings resulted only a slide improvements.
— : total plate count, aerobic spore count and moulds number of natural spice mixtu- res and spice mixtures fumigated under different conditions (the results are expressed as percents of the samples in the different rangs of contamination)Of contaminationUnfumigated spice mixtures
Fumigated spice mixtures400 g E0/m5 750 g E0/m5 1000 g EO/m55-6h 5lh 5h 7 - 8h 14h 17 - 18h 5h 5-6h22°C 31°C 13°C 18°C 23°C 31°0 34°C 20 °C 23°C 20°C 22°C
7 L. /■**When XOOO g of EO/nr was used for 5 to ° at 20°C no improvements were noticed iß . / comparison to fumigation with 400 g of m 5 or 750 g of E0/m3.It seems that only one intensified parameter, when others unchanged, cannot ess tially improve the effect of fumigation»The residues of Ethylene oxide were meaSu red immediately after fumigation and in intervals of a few days up to a few wees ' The quantity of residual Ethylene oxide initially relatively high - a few hundr® ppm. After a few days storage they fall “ s the values from 70 ppm to 1 7 5 ppm and constant tendency of falling. Two to thf weeks after fumigation they fell to zero respectively to a few ppm.
Being aware that the absence of EO residues do not represent the irrevocability of mixtures concerning residues, we believe that the question of EO residues is only a of principle but may serve only as a rough indicator of residual contamination in generThe question of residuals sets up the problem if to apply the fumigation or not. The answer to this is let to the plant technologist, who must estimate the smallest possiP-1, demage risk concerning microbiological aspect, economic aspect owing to spoilage of f°° ¡¡t health hasard aspect due to present microorganisms and health hasard aspect due to residues. The decision is not to be taken in a common way, but must be made with consia ration of all the mentioned moments and with full responsibility.Literature:1. DEGESCH - Deutsche Gesellschaft für Schädlingsbekämpfung MbH, Frankfurt am Main 1*Neue Mainzer Strasse 1, BDR v< ., t 12. Pravilnik o pogojih, ki jim morajo glede mikrobioloske neoporeönosti ustrezati zivi-1prometu, Ur.l. SFRJ 2/80, 11.1.1980 fl3. Pravilnik o metodah mikrobioloäkih analiz in superanaliz zivil, Ur.l.SFRJ 8/77,H'2|„4. Kishen S.A.E1: Determination of Ethylene oxide and methods of its recovery from fu®1gated substances. J.Sei.Food Agric. 1, 71 (1950) ,5. Eschmann K.H.: Gewürze - eine Quelle bakteriologischer Infektionen,Alimenta 4(1965/’
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