Effect of temperature and feed on the mineral content and the content of selected heavy metals in mealworm

Adámko á A., Mlček J., Adámek M., Fiše a M., Bo ko co á M., Bednářo á M., Hlobilo á V., Vojáčko á K. 2020. E ec o empe a u e and eed on he mine al con en and he con en o selec ed hea y me als in mealwo m. J. Elem., 25(3): 1077-1088. DOI: 10.5601/jelem.2019.24.4.1932 Jou nal o Elemen ology ISSN 1644-2296 ORIGINAL PAPER RECEIVED: 12 No embe 2019 ACCEPTED: 11 May 2020 EFFECT OF TEMPERATURE AND FEED ON THE MINERAL CONTENT AND THE CONTENT OF SELECTED HEAVY METALS IN MEALWORM* Anna Adámko á1, Jiří Mlček1, Ma in Adámek2, Mi osla Fiše a1, Ma ie Bo ko co á1, Ma ina Bednářo á3, Ve onika Hlobilo á1, Klá a Vojáčko á1 1 Depa men o Food Analysis and Chemis y Tomas Ba a Uni e si y in Zlin, Czech Republic 2 Depa men o Mic oelec onics B no Uni e si y o Technology, Czech Republic 3 Depa men o In o ma ion Technology Mendel Uni e si y in B no, Czech Republic Abs Ac Mine als a e impo an componen s o housands o enzymes and o he compounds in he body. Al hough he con en o mine als in he human body is small, hei impo ance is immense. Edible insec s can p o ide many o hese mine als in abundance, and a e he e o e hough o be a good sou ce o mic onu ien s. This s udy deal wi h he e ec o a ea ing empe a u e and eed on he mine al con en and on he con en o selec ed hea y me als in mealwo m (Teneb io moli o ). Mealwo m la ae we e kep a empe a u es o 15, 20 and 25°C, and ed wi h whea b an, len il lou and a mix u e o bo h. The ypes o eed o he expe imen al g oups we e chosen pu pose ully, conside ing he a ailabili y on si e, p ice and especially he impac on he nu i ion composi ion sui able o human. The concen a ions o he mos signi i- can elemen s in e ms o human nu i ion conce ns, ha is zinc and coppe , we e de e mined wi h induc i ely coupled plasma mass spec ome y. The esul s showed ha he no mali y condi ion was no achie ed o Ca, Fe, P and Pb (p<0.05). The e o e, hese da a we e compa ed using he K uskal-Wallis me hod, while ANOVA es was pe o med o he o he elemen s. The e was a s a is ically signi ican dependence o he Cd concen a ion on eed a a cons an ea ing empe a u e o 15°C and 25°C o e he en i e eed change ange. The esul s included a change in Mg o e he whole ange o moni o ed alues wi h a change o he ea ing empe a- u e and cons an eed o len ils-b an,and wi h a change o eed and cons an ea ing empe a- u e o 15°C. In con as , concen a ions o Na, P, Ca and Cu o e he whole obse ed ange o eed o ea ing empe a u e changes we e independen om he a iables. Wi h an app o- doc. Ing. Jiří Mlček, PhD., Depa men o Food Analysis and Chemis y, Tomas Ba a Uni e si y in Zlin, Va ečko a 275, 760 01 Zlín, [email p o ec ed] * This esea ch was suppo ed by he in e nal g an o TBU in Zlín [No. IGA/FT/2020/010] and by p ojec BUT in B no (No. FEKT-S-20-6215). 1078 p ia ely chosen ea ing empe a u e and eed, i is possible o ob ain mealwo m wi h speci ic nu i ional p ope ies o a a ge g oup o consume s. Keywo ds: Teneb io moli o , mine als, whea b an, len il lou , nu i ion, ea ing empe a u e, ICPMS. INTRODUCTION In e es in nu i ion is g owing cons an ly. Balanced in ake o all nu ien s is impo an o he heal h o consume s. Wi h 1.5-3 million species, insec s a e is he mos di e se class in he wo ld (Zielińska e al. 2015). Edible insec s we e used in he pas as adi ional ood, o example in China, whe e people a e silkwo ms pupae, which a e s ill consumed in many a eas o Sou hwes China (Feng e al. 2018). The ques ion o edible insec s is an inc easingly mo e popula opic o expe s in nu i ion as well as gene al public, also in coun ies whe e en o- mophagy is no common (Velíšek 2002, Ho niakoVá e al. 2010, Van Huis e al. 2013). The chance o using edible insec s as a aluable sou ce o p o- ein, a s, i amins and mine als is especially app ecia ed in a eas whe e he e a e sho ages o hese nu ien s (Velíšek 2002, Ho niakoVá e al. 2010, JóZe iak e al. 2016, Ge e e al. 2019). O he ad an ages a e highe eed con e sion, low g eenhouse gas emission, mo e op imized use o land and con e sion o seconda y o ganic ma e ials in o aluable p oduc s. This s a egy can lead o inancial sa ings and ecological ad an ages (De olia 1992, Ce i os 2011, amos elo Duy e al. 2011, Van B oekHoVen e al. 2015, Van Huis 2016). Insec s also ha e a g ea po en ial as eed, o example in aquacul u es (Van Huis 2016). The eason is hei high p o ein con en and he concen a ions o sulphu ic amino acids, which can be suc- cess ully used as eed o poul y (JóZe iak e al. 2016). Payne e al. (2016) concluded ha en omophagy does no ha e a wo se e ec on human heal h han ea ing con en ional mea ; on he con a y, i can lead o be e heal h. I is p esumed ha wi h he igh choice o a ea ing empe a u e and eed (die ), i is possible o modi y he nu i ional alue o insec s. Hence, i is necessa y o make nu i ional analyses o insec s depending on he applied eed and ea ing empe a u e in o de o acqui e he eques ed nu i ional alues. Edible insec s could be a possible al e na i e sou ce o mine als ha a e essen ial in human nu i ion. They a e impo an o biological p ocesses aking place in he body, which is why hey became he ocus o ou s udy. Mine al de iciencies can cause g ow h p oblems, immunological diso de s and men al de elopmen diso de s (Zielińska e al. 2015). I on and zinc a e especially impo an as hese mine als a e o en de icien in de eloping coun- ies ( umPolD sCHlü e 2013, manDi se a e al. 2019). Unlike plan sou ces, some insec s con ain bioa ailable i on, which is be e dissol ed and used 1079 by a li ing o ganism (la unDe-DaDa e al. 2016). la unDe-DaDa e al. (2016) epo s ha “popula ions subsis ing p edominan ly on plan ood sou ces o i on in he die ha e a high incidence o i on-de iciency anemia (IDA).” The combina ion o coppe and i on is e y impo an o he o ma ion o blood cells (Velíšek 2002, Ho niakoVá e al. 2010). inke (2002) mea- su ed he coppe and i on con en in mealwo m. The coppe con en was 6.1 mg kg-1 and ha o i on eached 20.6 mg kg-1 ( inke 2002). Zielińska e al. (2015) de e mined he coppe con en a 18.6 mg kg-1 and he i on con- en a 32.9 mg kg-1. Zinc is he second mos abundan me al in o ganisms, wi h 2-4 g ound in he human body. I is a biologically essen ial ace elemen , c i ical o he cell g ow h, de elopmen and di e en ia ion (John 2010). The amoun o zinc was de e mined o be 52.0 mg kg-1 ( inke 2002) and Zielińska e al. (2015) epo s a zinc con en o 112 mg kg-1. The mos common hea y me als include cadmium (Cd) and lead (Pb). Cadmium is a po en human ca cinogen ha p ima ily causes cance o he p os a e, lung, kidney and panc eas. Lead is oxic o humans and ani- mals, and i s pe sis ence causes long- e m occu ence in he en i onmen (JomoVa 2011). Dange ous concen a ions o hese me als ha e no been de ec ed in common a med insec s. MATERIAL AND METHODS Mealwo m la ae (Teneb io moli o ) we e used o he analysis. Samples we e bough om he company Radek F ýželka, B no, while he ea ing o la ae was ca ied ou by Ma ie Bo ko co á, Assoc. P o . a Mendel Uni e si y in B no. The insec s we e di ided in o 3 expe imen al g oups. The i s g oup was ed only whea b an, he second ecei ed only len il lou , and he hi d g oup was ed a mix u e o 50% whea b an and 50% len il lou . Fo each expe imen al g oup, he eed was weighed, and he weigh o a a ion was he same o all g oups. Nu i ion alues o he eed we e (pe 100 g): Whea b an/c ude: ene gy alue 1 210 kJ/292 kcal, a 5.3 g, o which sa u a ed a y acids 0.88 g, ca bohyd a es 24.9 g, o which suga s 2.2 g, ib e 40.2 g, p o ein 16.2 g, sal 0.1 g. P oduce : Coun y Li e, s . o., Be oun 1. Len il lou : ene gy alue 1250 kJ/298 kcal, p o ein 24.1 g, a s 2.0 g, o which sa u a ed a y acids 0.5 g, ca bohyd a es 49.6 g, o which suga s 2.2 g, ib e 11.4 g, sal 6.7 mg. P oduce : Ex udo Bečice s . o., Bečice 7, 375 01 Týn nad Vl a ou. Be o e analysis, he samples we e p epa ed as ollows: mealwo m la ae in ul ima e and penul ima e ins a de elopmen (wi h a ull body leng h jus be o e pupa ion) we e aken om he ea ing expe imen . The nex s ep was as ing he insec s o 48 hou s, sac i icing hem in boiling wa e (100°C) 1080 and d ying a 105°C. Samples hus p epa ed we e homogenized and s o ed in a cooling box a 4 o 7°C un il analysis. Samples o exc emen analysis we e aken a 20°C, homogenized and s o ed a 4 o 7°C un il analysis. A e he expe imen , he subs a e wi h exc emen s was aken om he ea ing boxes. These samples we e homogenized and s o ed a 4 o 7°C un il analysis. De e mina ion o mine al elemen s Sample p epa a ion The olume ic equipmen was soaked in 2% ANALPURE ul a HNO3 o e nigh and ho oughly insed wi h Pu elab Elga wa e be o e use. High pu i y 18.2 MΩcm wa e was ob ained om a Pu elab Classic Elga pu i ica- ion sys em o use in he p epa a ion o all solu ions. HNO3 was deli e ed as concen a ed 65% g ade ANALPURE ul a. Solid samples we e decomposed wi h a mix u e o 65% ANALPURE ul a HNO3 and ANALPURE ul a H2O2 in a mic owa e sys em Miles one E hos One. Each sample was weighed, di ided in o app oxima ely 1g indi idual samples, and added 5 mL o 65% ANALPURE ul a HNO3 and 1 mL o ANALPURE ul a H2O2. A e wa ds, all essels we e closed and inse ed in o he segmen o adjus he wo king p essu e (pe o med wi h an adjus - able o que w ench), and hen inse ed in o a wis ing o o . The nex s ep was he decomposi ion p ocess acco ding o a empe a u e p og amme sui - able o ce eal ma e ials. Two se s o calib a ion s anda d se ies we e p e- pa ed o ma ch he expec ed concen a ion anges in he samples o he 25 and 12 elemen s selec ed o his s udy - high s anda d se ies: Be, Zn, Cu, Ni, Al, Ga, Mg, Co, Li, Sc, Ag, Mn, S , Ba, TI, Bi, Ce, Cs, Ho, In, Rh, Ta, Tb, U and Y a 3–35 µg L-1 and low s anda d se ies: As, Ca, Cd, C , Fe, Hg, K, Na, Pb, Se, Sn and Ti a 0.5-1.0 µg L-1. Quali y con ol (QC) S anda d solu ions in 2% HNO3 we e p epa ed om 3-35 µg L-1 o he mul i- elemen ICP s anda d (Analy ika, CR) con aining he elemen s: Be, Zn, Cu, Ni, Al, Ga, Mg, Co, Li, Sc, Ag, Mn, S , Ba, TI, Bi, Ce, Cs, Ho, In, Ta, Tb, U and Y in he o iginal concen a ion (3-35) µg L-1 and hal he concen a ion (1.5-17.5) µg L-1. An in e nal s anda d (103Rh) was used wi h 10 µg L-1 solu- ion o imp o e he accu acy and u h ulness o he measu emen s. The o iginal mul i-elemen ICP s anda d (Analy ika,CR) wi h he con- cen a ion o 335 µg L1 o indi idual elemen s was used as a con inuing cali- b a ion e i ica ion (CCV) s anda d. Fo he concen a ion alues, see Table 1. Ins umen a ion Analyses we e ca ied ou on a quad upole-based The mo Scien i ic iCAP Qc induc i ely coupled plasma-mass spec ome e (ICP-MS), equipped wi h nickel cones, a Pel ie -cooled low- olume conical qua z sp ay chambe 1081 o imp o e he ins umen ’s pe o mance, a concen ic PFA nebulize , a col- lision cell (QCell) wi h helium o emo e undesi able molecule ions o o disc i- mina e hei kine ic ene gy (CCT and KED mode), a pe is al ic sample deli e y pump, and a Ce ac 520 au osample . The ins umen ’s ope a ing se ings we e op imized o he analysis o samples a e MW decomposi ion wi h ela i ely simple ma ices. Mass calib a ion and de ec o c oss-calib a ion we e pe o med acco ding o he ins umen manu ac u e ’s ins uc ions, using he p esc ibed solu ions ob ained om The mo. A sensi i i y check using a 10 µg L-1 Ba, Be, Bi, Ce, Co, In, Li, Ni, Pb, U uning solu ion p eceded he onse o he analy ical measu emen s. The esul ing pe o mance epo included impo an sensi i i y da a, such as he ex en o he o ma ion o oxide ions (156CeO+/140Ce+) and doubly cha ged ions (137Ba2 +/137Ba+), in addi ion o coun a es o he uning solu ion elemen s, whe eby he op imized s a us o he ins u- men could be assessed. Elemen s ha may dis ub he quan i ica ion o elemen s due o in e - e ences we e sc eened. Al hough elemen s such as oxygen (O), a gon (A ) and chlo ine (Cl) may also be p esen and complexed wi h he o he elemen s, he eby gene a ing in e e ences, hey we e elimina ed using he CCT/KED mode o selec ed elemen s. Fu he mo e, an in e nal s anda d (103Rh) was used o imp o e he accu- acy and u h ulness o he measu emen s. This elemen /iso ope was used as a uni e sal elemen he weigh o which, esp. m/z o 103, lies in he middle o he ange o masses o commonly de e mined elemen s (7Li – 238U). The alida ion o he analy ical me hod was ensu ed by conduc ing a simul aneous analysis o he ce i ied e e ence ma e ial CRM 12-02-01 (Bo ine Li e ). Analy ical da a ob ained o all de e mined elemen s we e ound wi hin he con idence in e al gi en by he manu ac u e o he CRM o hese elemen s (kuCe a 1990). Table 1 Concen a ion o indi idual elemen s in mul i-elemen ICP s anda d (Analysis) Elemen STD25 (µg L-1 ) Be 35 +/- 1.75 Zn 20 +/- 1.00 Cu, Ni 15 +/- 0.75 Al, Ga, Mg 10 +/- 0.50 Co, Li, Sc 8 +/- 0.40 Ag, Mn 6 +/- 0.30 S 5 +/- 0.25 Ba, TI 4 +/- 0.20 Bi, Ce, Cs, Ho, In, Ta, Tb, U, Y 3 +/- 0.15 1082 S a is ical e alua ion The da a we e analyzed in Excel 2013 (Mic oso Co po a ion, USA) and S a is ica Cz e sion 12 (S a So , Inc., USA). The esul s we e exp essed as means ± s anda d de ia ion. S a is ical p ocessing and da a e alua ion p oceded h ough se e al s eps. The Shapi o-Wilk es o no mali y was used i s . The esul s showed ha he no mali y condi ion was no obse ed o Ca, K, Fe and Pb (p<0.05). Subsequen ly, he Le ene, and he B own and Fo sy he (HOV) es s o homogeni y we e pe o med. In bo h es s, he esul s showed ha he homogeni y condi ion was no ul illed o P, Ca, K, Fe and Pb. The e- o e, he da a we e compa ed using he K uskal-Wallis me hod. An ANOVA es was pe o med o he emaining elemen s. Finally, he Tukey HSD es s we e ca eid ou on he ANOVA da a a a cons an ea ing empe a u e o eed. RESULTS AND DISCUSSION Insec s can be a aluable sou ce o a wide ange o mine als. Among signi ican mine als and selec ed hea y me als, his esea ch ocused on Ca, P, K, Na, Zn, Cu, Fe, Cd and Pb, as i can be seen in Table 2. I migh ha e been suspec ed ha he KED-mode should ha e been mo e a ec ed by he m/z di e ences be ween he in e nal s anda d and analyzed elemen s due o he e ec s o he ini ial kine ic ene gy and collision a e o ions and He-gas. The di e ence in he collision a e could lead o less e icien com- pensa ion by he in e nal s anda d wi h an inc ease in he m/z di e ence. While he e we e clea di e ences in he signal loss a io be ween he KED- and s anda d-mode, depending on he size and m/z o each elemen , he a ios we e consis en enough so ha he e was li le o no e ec indica - ing which in e nal s anda d would be p e e able o use. Calcium is one o he mos essen ial elemen s in nu i ion because i ensu es he unning o me abolic p ocesses as well as enzyma ic and ho - monal eac ions. In he mealwo m samples analyzed, i s con en inc eased wi h he ea ing empe a u e in ea men s whe e he mix u e o b an and len ils was used as a eed. Fo he combined p o ein and ca bohyd a e die (len ils-b an), a highe calcium con en was measu ed a 15°C han a 20°C and 25°C. The e was a endency owa ds highe Ca om 20°C. The highes con en o calcium in he body o mealwo m was de e mined a 25°C o len- il lou die (0.453 mg kg-1in DM). A simila calcium con en was de e mined in mealwo m ed b an and main ained a 25°C (0.450 mg kg-1 DM), and ecei ing he mix u e o len ils and b an and kep a 15°C o (0.452 mg kg-1 DM). The di e ence in he calcium con en be ween he wo ypes o die is minimal. The analysis showed ha he amoun o calcium in ake in eed is e y simila o he calcium con en in exc emen s, sugges- 1083 Table 2 Con en o de e mined mine al elemen s and selec ed hea y me als in mealwo m (Teneb io moli o ) depending on he ea ing empe a u e and eed G oup Type o eed Ca (µg kg-1) P (mg kg-1) K (mg kg-1) Na (mg kg-1) Zn (mg kg-1) Cu (mg kg-1) Fe (mg kg-1) Cd (µg kg-1) Pb (µg kg-1) MSD MSD MSD MSD MSD MSD MSD MSD MSD Feed b an 375.5 2.3 419.7 19.2 293.1 1.8 2.6 0.3 33.9 3.4 11.7 0.6 0.6 0.6 50.6 2.9 64.8 5.2 Feed len ils 378.5 0.7 115.3 2.5 295.8 0.3 4.7 0.3 11.1 0.2 8.2 0.2 5.4 2.7 9.9 0.6 41.8 18.3 15°C ea ing b an 437.5 1.4 395.4 14.8 346.1 5.0 71.0 7.6 52.7 2.2 21.9 1.1 12.1 0.9 52.2 3.1 49.9 5.0 20°C ea ing b an 445.5 7.5 383.9 18.4 352.2 4.3 71.2 7.1 51.6 2.4 21.9 1.1 14.4 0.5 52.1 4.6 56.5 5.8 25°C ea ing b an 450.8 1.0 439.5 14.9 352.4 0.9 93.7 4.2 56.2 2.3 27.1 0.9 16.7 0.3 62.8 3.2 51.6 3.9 15°C ea ing len ils - b an 452.8 8.8 361.0 20.4 358.9 3.0 69.7 3.5 46.8 3.5 22.0 1.2 15.5 0.3 57.6 2.8 50.4 3.2 20°C ea ing len ils - b an 441.3 12.6 380.8 40.8 356.3 1.4 75.0 3.8 46.5 3.7 23.3 1.3 14.1 0.3 53.8 3.7 57.8 0.9 25°C ea ing len ils - b an 449.6 5.9 379.0 15.1 358.0 1.0 79.3 4.9 47.0 1.9 23.9 1.0 15.8 0.5 52.0 2.7 59.5 2.0 15°C ea ing len ils 437.9 7.9 440.2 12.7 351.7 0.2 96.9 4.6 54.4 2.6 25.4 1.1 20.2 1.5 75.4 3.7 71.7 2.0 20°C ea ing len ils 439.5 6.8 432.0 9.7 352.4 0.7 95.1 5.1 49.5 1.7 25.1 1.2 18.5 0.6 66.7 3.4 51.4 4.9 25°C ea ing len ils 453.3 3.7 411.6 9.7 359.2 0.3 94.1 4.3 49.5 1.5 25.3 0.9 21.4 1.2 67.8 2.6 57.1 9.5 Exc emen s b an 377.4 1.5 726.3 28.6 294.6 1.2 2.7 0.1 44.8 1.4 15.2 0.3 47.4 3.1 53.8 3.2 241.5 13.6 Exc emen s len ils 376.7 1.3 188.5 4.7 294.1 1.0 2.0 0.1 17.1 0.5 9.3 0.4 17.9 0.5 14.7 1.2 32.2 0.9 Exc emen s len ils - b an 415.9 40.3 301.4 5.9 324.7 31.5 2.5 0.2 21.1 0.7 10.1 0.4 23.7 0.5 22.9 1.2 85.8 3.2 1084 ing ha he calcium in ake was su icien o his ea ing egime and did no accumula e in he la a’s body. Ano he mac onu ien impo an in me abolism and ene gy ans o ma- ion (ATP, AMP) ha we analyzed was phospho us. When mealwo m la ae we e ea ed a a empe a u e o 20°C o lowe , he e is a highe p opo ion o phospho us in he g oups ed wi h len ils. As he ea ing empe a u e ose, he phospho us con en dec eased sligh ly in hese g oups. The s udy shows ha eeding wi h b an, which has abou h ee- old mo e phospho us han len ils, led o a smalle amoun o phospho us being de ec ed in he la al body. De e mina ion o he phospho us con en ela i e o he eed supplied o mealwo m (Teneb io moli o ) was s udied by oonincx e al. (2015), who desc ibed a change in he phospho us con en anging om 7700 mg kg-1 DM o 9700 mg kg-1 DM. Signi ican changes in a ca bohyd a e and p o ein die did no signi ican ly a ec he phospho us con en . Howe e , he esul s o he ci ed s udy do no co espond o ou da a. Po assium and sodium a e impo an o osmo ic p essu e and acid-base balance. Bo h eeds a e compa able sou ces o po assium, and his was mani- es ed in he bodies o mealwo m la ae, wi h he highes po assium con en iden i ied in he g oup ea ed a 25°C. Acco ding o he nu i ional ecom- menda ion, he sodium o po assium a io should be om 1:1 o 1:4. Teneb io moli o ul ills his equi emen . The highes measu ed alues o sodium we e in he g oup ed wi h len ils, he ype o eed compa able o b an bu wi h a highe p opo ion o his mac onu ien . A signi ican bene i o edible insec s as ood o eed is he con en o zinc and coppe , he wo me als which play se e al unc ions in he body o an animal (nu ien me abolism, ep oduc ion, bone o ma ion and hema- opoiesis). The a e age zinc con en in all moni o ed g oups anged om 46 o 56 mg kg-1 DM, while he a e age coppe con en anged om 21 o 27 mg kg-1 DM. In e ms o nu i ional ecommenda ions (Zn 10 mg kg-1 and Cu 1 mg kg-1), he Teneb io moli o species can be a signi ican sou ce o hese mine als. The Zn and Cu le els in a ca bohyd a e eed a e highe , which was e idenced by he zinc con en in he expe imen al g oups o insec s a 20°C, bu did no co espond o he de e mined coppe con en . The combina ion o coppe and i on, wo me als o which edible insec s can be a good sou ce o , is c ucial o he o ma ion o blood cells. In he samples submi ed o ou esea ch, an a e age i on alue o 12 mg kg-1 o 21 mg kg-1 DM was de e mined. This is he same o lowe han esul s p o ided by o he au ho s. inke (2004) epo s up o 54 mg kg-1. The e o e, he i on con en is gene ally equal o highe hen he i on con en in bee o po k. meneZes e al. (2010) de e mined 49 mg kg-1 in aw bee and 21 mg kg-1 in aw po k, Velíšek (2002) epo s 22-30 mg kg-1 o bee and 10-20 mg kg-1 o po k, and Ge Be e al. (2009) de e mined 16.1 mg kg-1 ( ib-eye) and 14.2 mg kg-1 (b iske ) in aw bee and 9.8 mg kg-1 (neck s eak) and 8.3 mg kg-1 (belly) mg kg-1 in aw po k. A 25°C, he i on con en 1085 o he mealwo m la ae ed len ils is highe han in hose ed b an, bu in he exc emen s analyzed, he i on con en was ound in he g oups ece ing b an (Velíšek 2002, Ho niakoVá e al. 2010). When analyzing exc emen s om he la ae o he species analyzed, he highe con en o mine als was ound in exc emen s han in he eed. The eason o his may be he binding o mine als o indiges ible ibe in he die . In his s udy, we also looked a he sa e y o edible insec ma e ial in e ms o i s con en o hea y me als such as cadmium and lead, which is mus be moni o ed due o accumula ion om eed in he body o insec s. Hea y me als a e a isk posed by edible insec consump ion. O he h ea s a e mic obiological, physical and alle genic ones (CaPPelli e al. 2020). The measu ed cadmium con en anged om 0.052 o 0.075 mg kg-1 DM in he expe imen al g oups. These alues do no exceed he limi o 0.5 mg kg-1 in he esh s a e (FW) se o c us aceans, in o which edible insec s a e cu en ly classi ied because o a lack o speci ic legisla ion. Simila ly, he lead con en in he analyzed samples anged om 0.049 o 0.072 mg kg-1 DM. The limi o his me al is he same as o cadmium, i.e. 0.5 mg kg-1 in FW (EC/1881/2006). Conce ning lead and cadmium, he ood appea s sa e. The same issue o he mine al con en in Teneb io moli o was deal wi h by o he au ho s. Acco ding o nowak e al. (2016), he main mine al subs ances con ained in mealwo m we e i on in he amoun o 3.29 mg 100 g-1 DM, coppe 1.86 mg 100 g-1 DM, zinc 11.2 mg 100 g-1 d y ma e , po assium 835 mg 100 g-1 d y ma e , magnesium 304 mg 100 g-1 DM, sodium 57 mg 100 g-1 DM and calcium 41 mg 100 g-1 DM (nowak e al. 2016). inke e al. (2015) de e mined mine als a le els: calcium 156 mg kg-1, phos- pho us 2640 mg kg-1, magnesium 620 mg kg-1, sodium 225 mg kg-1, po assium 3350 mg kg-1, chlo ine 1760 mg kg-1kg, i on 20.7 mg kg-1, zinc 49.5 mg kg-1, coppe 8.3 mg kg-1, manganese 3.2 mg kg-1and selenium 0.123 mg kg-1. Baek e al. (2019) de e mined mine als in eeze d ying ma e ial o meal- wo ms wi h mois u e a le els: calcium 341.9 mg kg-1, phospho us 5931.7 mg kg-1, sodium 1082.3 mg kg-1, po assium 8651.5 mg kg-1 and i on 20.7 mg kg-1. aVZanaaDii e al. (2012) de e mined he mine al con en o la ae and adul s o Teneb io moli o . The mos abundan elemen s we e po assium, phospho us, sodium, magnesium and calcium, while he smalles quan i ies we e de e mined o zinc, i on and coppe ( aVZanaaDii e al. 2012). These s udies di e signi ican ly in esul s, possibly due o di e ences in eeds and ea ing condi ions, which he au ho s did no speci y in de ail. Fo his eason, some esul s o ou s udy may di e om he li e a u e da a. The esul s o s a is ical p ocessing show ha he e is a di e ence be ween all he measu ed elemen s (p<0.050) excep om po assium. The esul s o he Tukey HSD es s and he g aphical ep esen a ion o he esul s in he o m o mean and s anda d de ia ion show a s a is ically sig-