Electronic Nose In Edible Insects Area

Po a ina s o Slo ak Jou nal o Food Sciences Volume 11 446 No. 1/2017 Po a ina s o Slo ak Jou nal o Food Sciences ol. 11, 2017, no. 1, p. 446-451 doi: h ps://dx.doi.o g/10.5219/785 Recei ed: 18 Ma ch 2017. Accep ed: 17 May 2017. A ailable online: 14 July 2017 a www.po a ina s o.com © 2017 Po a ina s o Slo ak Jou nal o Food Sciences, License: CC BY 3.0 ISSN 1337-0960 (online) ELECTRONIC NOSE IN EDIBLE INSECTS AREA Ma in Adámek, Anna Adámko á, Ma ie Bo ko co á, Jiří Mlček, Ma ina Bednářo á, Lenka Kouřimská, Jose Skácel, Michal Řezníček ABSTRACT Edible insec is app aised by many cul u es as delicious and nu i ionally bene icial ood. In wes e n coun ies his commodi y is no ully app ecia ed, and he wo ies abou edible insec ood sa e y p e ail. Elec onic noses can become a simple and cheap way o secu ing he heal h sa e y o ood, and hey can also become a ool o e alua ing he quali y o ce ain commodi ies. This esea ch is a pilo p ojec o using an elec onic nose in edible insec culina y ea men , and his manusc ip desc ibes he phases o edible insec culina y ea men and me hods o dis inguishing mealwo m (Teneb io moli o ) and gian mealwo m (Zophobas mo io) using simple elec onic nose. These species we e measu ed in he li e s age, a e killing wi h boiling wa e , a e d ying and a e inse ing in o he chocola e.The sensing de ice was based on he A duino Mega pla o m wi h he abili y o s o e he eco ded da a on he SD memo y ca d, and wi h he possibili y o communica e ia in e ne . Da a analysis shows ha e en a simple, cheap and po able elec onic nose can dis inguish be ween he di e en s eps o culina y ea men (na i e samples, d ied samples, samples en iched wi h chocola e o cooking) and selec ed species. Ano he bene i o he elec onic nose could be i s u u e in oduc ion in o he con ol mechanisms o ood secu i y sys ems (e.g. HACCP). Keywo ds: e-nose; edible insec ; mealwo m; gian mealwo m; A duino INTRODUCTION Edible insec is app aised by many cul u es as delicious and nu i ionally bene icial ood. On he con a y, in he wes e n coun ies, edible insec is ea ed wi h disgus , being associa ed mo e wi h di han wi h ood (Yen, 2009; Looy, Dunkel, and Wood, 2014). Despi e he many bene i s (sui able nu i ional alues, low ecological bu den and low economic cos ) his commodi y is no ye ully app ecia ed in wes e n coun ies (Tan e al., 2015; Adámko á e al., 2016). Fo his eason, insec in hese coun ies is used mainly as menu en ichmen , delicacy, sough a e mainly because o i s senso y p ope ies (Bo ko co á e al., 2009). Tas e o edible insec is plen i ul, depends mainly on he en i onmen and ood. Ano he aspec ha in luences he edible insec senso y a ibu es is he culina y p ocessing, du ing which insec akes he as e o he added ing edien s. Majo i y o insec species is almos wi hou as e due o exoskele on. Tas e and smell o insec a e made by he phe omones on he body su ace, he e o e i is no ecommended o wash he insec p io o he ea ing (Ramos-Elo duy, 1998). Al hough he sense o smell is one o he oldes human senses (Hanboonsong, 2010; Ramos-Elo duy e al., 1997), i can be insensi i e on his accoun and smell pe cep ion can be s ongly subjec i e. Odou pe cep ion is based on a se ies o chemical eac ions ha occu upon con ac wi h he gas molecules wi h smell ecep o s, which induces he low o elec ical signals h ough he neu ons ha a e p ocessed by he b ain. In humans, he su ace o he ol ac o y mucose memb ane c ea es an a ea o abou 5 cm2, whe e 1000 di e en ypes o ol ac o y ecep o s a e sca e ed. On he con a y, he ol ac o y mucosal su ace o dog occupies an a ea up o 170 cm2, which p o es hei supe io sense o smell. Humans can dis inguish a maximum o 4000 di e en compounds. To be able o dis inguish di e ences in in ensi y o he odou , i is necessa y o inc ease he in ensi y by a leas 30%. The sense o smell ha e he s onges e ec on he men al s a e o a human o all his senses. In highe concen a ions, odo s can e en cause a ious heal h p oblems (nausea, headache), o con e sely, a pleasu e eeling (Ca lsson and Kalino á, 2005; The eNose Company, 2016). Humans a e able o dis inguish many smells and pe cei e hei di e en in ensi ies. Howe e , he sense o smell is o en insu icien , and i is necessa y o use o he me hods o sepa a ing and inc easing he concen a ion o odo s, which a e no iced by human (ol ac ome y). The o he g oups a e ools ha moni o he concen a ion o each a oma comple ely independen ly o he human sense o smell – elec onic noses (The eNose Company, 2016; Gopal, 2015). These de ices a e usually equipped wi h se e al semiconduc o gas senso s, each one sensi i e only Po a ina s o Slo ak Jou nal o Food Sciences Volume 11 447 No. 1/2017 o a ce ain ype o gas o g oup o gases. They also con ain a da abase o e e ence samples which se es o he e alua ion o he measu ed samples. Fi s , you need o " each" he elec onic nose he di e en smells. Mo e accu a e de ices may u he combine di e en me hods o measu ing he concen a ion o subs ances in he gas. Elec onic noses may be use ul no only as a pa o sa e y sys ems (de ec ion o lammable, haza dous subs ances o humans), and en i onmen al p o ec ion (de e mina ion o ai pollu ion), bu also in heal h ca e, and especially in he ood indus y (Ca lsson and Kalino á, 2005; Gopal, 2015). In he ood indus y, a scen ha sa is ies consume s is one o he mos impo an senso y p ope ies (Haščík e al., 2013). To assess i , knowledgeable people in he ield o senso y pe cep ion a e used (Kinclo á, Ja ošo á and T emlo á, 2004). Howe e , layman e alua es he smell only subjec i ely, based on his expe ience and p e e ences. People commonly use he sense o smell o assess he quali y o he ood (consume connec s esh ood wi h a pleasan smell and a de e io a ing ood wi h unpleasan smells - odou ). Howe e , his o m o assessmen is no exac , so i is p e e able o use a mo e p ecise me hod based on elec onic senso s and compu e p ocessing – an elec onic nose. Using he elec onic nose can p e en economic losses and heal h complica ions due o spoiled ood poisoning. The aim o his wo k was o es edible insec samples using simple and cheap p o o ype o elec onic nose, in o de o e alua e i s abili y o iden i y insec species and s age o p ocessing h ough simple culina y ea men . MATERIAL AND METHODOLOGY Insec La ae o mealwo m (Teneb io moli o ) and gian mealwo m (Zophobas mo io) we e used o he analysis. Samples we e bough in pe s o e K mi a Hos i ice. Insec p ocessing The insec was aised in op imal condi ion o de elopmen o each species. Bo h species we e ed wi h b ans and a mix u e o chopped ege ables and ui s. P io o he analysis la ae in he las and penul ima e ins a de elopmen ( he ull leng h o he body jus be o e pupa ion) we e collec ed om b eeding o subsequen culina y p ocessing and measu emen . Measu emen o gas concen a ions Measu emen o gas concen a ions was done using he expe imen al p o o ype o elec onic nose (Figu e 1), cons uc ed as a simple, cheap and mobile de ice. The ool i sel was based on he A duino Mega pla o m con olled by ATmega1280 mic ocon olle wi h he abili y o s o e he eco ded da a on he SD memo y ca d, and wi h he possibili y o communica e wi h he web se e . The measu ing cell was equipped wi h senso s based on he chemo- esis i e p inciple. I uses MQ-6 senso (Zhengzhou Winsen Elec onics Technology Co., L d, Zhengzhou, China), which is sensi i e especially o he p opane o isobu ane (300 – 10000 ppm) and less sensi i e o alcohol. O he senso s a e MQ-3 (Zhengzhou Winsen Elec onics Technology Co., L d, Zhengzhou, China), which is e y sensi i e o alcohol (25 – 500 ppm) and MQ- 8 senso (Zhengzhou Winsen Elec onics Technology Co., L d, Zhengzhou, China), used o de ec hyd ogen (100 – 1000 ppm). This de ice should only compa e i s measu emen s among hemsel es o inal da a e alua ion, and p ecise measu emen o absolu e concen a ion o each gas molecules wi hin he smell was no aken in o accoun . The e o e, we used he plugging ecommended by he manu ac u e , wi hou subsequen calib a ion o e alua ing he absolu e gas concen a ion. US ol age [V] om he indi idual senso s was con e ed o a digi al alue d [-] ( ol age o 0V and 5V co esponds o a digi al le el 0 and 1023) using he in e nal 10-bi A/D mic ocon olle con e e s. These alues we e hen ma hema ically p ocessed. Insec culina y p ocessing and smell e alua ion Measu emen s we e done in se e al s ages. A e s a ing o 24 hou s he i s measu emen was done. Subsequen ly, he insec was killed wi h boiling wa e (100 °C) and he second measu emen was ca ied ou . Figu e 1 Expe imen al p o o ype o elec onic nose. Po a ina s o Slo ak Jou nal o Food Sciences Volume 11 448 No. 1/2017 a) TM a e killing wi h boiling wa e b) ZM a e killing wi h boiling wa e c) TM a e d ying d) ZM a e d ying e) Chocola e wi h TM samples ) Chocola e wi h ZM samples Figu e 2 Insec samples a e each p ocessing phase. Figu e 3 Example o ime dependence o da a o each o he senso s MQ-8, MQ-6 and MQ-3 in samples o d ied la ae o he gian mealwo m (Zophobas mo io). 0 100 200 300 400 500 600 700 0 100 200 300 400 500 600 d [-] [s] MQ-8 MQ-6 MQ-3 Po a ina s o Slo ak Jou nal o Food Sciences Volume 11 449 No. 1/2017 A e d ying a 105 °C o 120 minu es, he hi d measu emen was done. The las measu emen was pe o med a e inse ing he d ied la ae in o a bowl and pou ing wi h chocola e o cooking (Nes lé Czech L d., P aha). Samples a e each p ocessing phase a e shown in Figu e 2. S a is ical analysis Each measu emen was ca ied ou h ee imes. Da a was p ocessed and e alua ed using he applica ions Excel 2013 (Mic oso Co po a ion, USA) and Gnuplo 5.0: an in e ac i e plo ing p og am (Williams and Kelley, 2016). RESULTS AND DISCUSSION The esul s p esen ed a e da a om i s a ailable measu emen s o insec p ope ies in di e en s ages o culina y p ocessing gained using he simple elec onic nose. A ailable li e a u e did no p esen any compa able da a. The da a ob ained o each o he senso s MQ-8, MQ-6 and MQ-3 was used o c ea e cu es o show he dependency on measu ed ime. Time o measu emen was se o 600 s. Example o ime dependence is shown in Figu e 3. Each cu e was used o ob ain basic s a is ical quan i ies: mean, s anda d de ia ion, minimum and maximum. Mean alues we e inse ed in o Table 1 and in o a 3D g aph Table 1 Mean alues o each senso and phase o culina y p ocessing. mealwo m (Teneb io moli o ) gian mealwo m (Zophobas mo io) Sample MQ-8 MQ-6 MQ-3 Sample MQ-8 MQ-6 MQ-3 li e la ae li e la ae 1 74.4 186.2 590.3 1 72.1 188.3 598.2 2 77.8 200.5 628.6 2 71.9 186.1 593.4 3 74.2 195.1 617.2 3 73.0 184.4 589.5 M 75.5 193.9 612.0 M 72.4 186.3 593.7 ±SD 2.0 7.2 19.7 ±SD 0.6 2.0 4.3 la ae killed wi h boiling wa e la ae killed wi h boiling wa e 1 100.2 281.5 679.3 1 98.3 287.7 661.3 2 84.0 219.6 640.5 2 91.6 220.5 628.9 3 72.5 199.3 617.5 3 75.5 191.9 599.1 M 85.6 233.5 645.7 M 88.5 233.4 629.7 ±SD 13.9 42.8 31.3 ±SD 11.7 49.2 31.1 d ied la ae d ied la ae 1 66.9 172.6 579.6 1 84.1 210.8 635.4 2 66.0 172.7 574.8 2 82.7 217.2 639.0 3 66.7 175.2 565.0 3 88.7 213.8 645.2 M 66.5 173.5 573.2 M 85.2 213.9 639.9 ±SD 0.5 1.4 7.4 ±SD 3.1 3.2 5.0 la ae in chocola e la ae in chocola e 1 96.4 267.0 806.1 1 97.2 263.2 800.9 2 93.6 257.6 789.4 2 103.0 263.9 799.5 3 97.9 261.2 799.4 3 97.2 257.0 785.9 M 95.9 261.9 798.3 M 99.1 261.4 795.4 ±SD 2.2 4.8 8.4 ±SD 3.4 3.8 8.3 Figu e 4 Measu ed spo s g aph. Po a ina s o Slo ak Jou nal o Food Sciences Volume 11 450 No. 1/2017 using he Gnuplo applica ion. The esul s o ou analyses sugges ha e en he simple elec onic nose can ecognize he species o edible insec s and phase o i s culina y p ocessing. Figu e 4 shows a g aph o measu ed alues (smell) moni o ed by he each gas senso o mealwo m (Teneb io moli o ) and gian mealwo m (Zophobas mo io) a e s a ing – in he na i e s a e, a e killing (boiling wa e 100 °C), a e d ying (105 °C) and a e pou ing wi h chocola e o cooking. In he g aph we can dis inguish di e en pa s (smells) o la ae in he na i e s a e, d ied samples and la ae in chocola e o cooking. Values o samples in chocola e a e e y simila in each species. The di e ence be ween species is clea in na i e and d ied samples. Values o samples a e killing wi h boiling wa e a e sca e ed h ough he g aph. This may be due o ele a ed empe a u e and humidi y, o which he senso s a e sensi i e and which we e no measu ed and co ec ed. I is supposed ha by de ec ing he scen i will be possible no only o e alua e he dange o spoiled ood ha can cause oodbo ne illness, bu also he a ious s ages o echnological p epa a ion and species. This could be used o documen he sc eening o oods o a oid hei po en ial spoo ing. The in o ma ion ob ained may se e as a basis o exclusion o ood om he ood chain. In he case o b eeding o edible insec s, his may also se e as a p ima y sc eening, no only o he species, bu also o e alua e he amoun o dead indi iduals in he ea ing box. Using he elec onic nose o moni o ing he scen s o insec s is examined in o he a eas, e.g. he con ol o ola ile subs ances eleased om co on bolls in esponse o eeding by s ink bugs (Degenha d , G eene and Khalilian, 2012; Hende son e al., 2010). The o he a ea is he con ol o he deg ee o insec in es a ion in whea , when Zhang and Wang (2007) p o ed i is possible o e alua e he ood aging and insec in es a ion in whea using he comme cial E-nose (PEN2) comp ising 10 me al-oxide semiconduc o (MOS) senso s. Simila ly Wu e al. (2013) p o ed he possibili y o de ec he p esence o ed lou bee le (T ibolium cas aneum) using he elec onic nose in whea wi h ce ain humidi y, howe e , hei elec onic nose did no de ec he p esence o us y g ain bee le (C yp oles es e ugineus). Also e alua ion o ice in es a ion by Nilapa a a lugens was ca ied ou using elec onic nose (Zhou and Wang, 2011). Elec onic nose can be used o p ecisely se up he bai used in boll wee il e adica ion p og ams (Suh, Ding and Lan, 2011). A ailable li e a u e also men ions and demons a es he possibili y o using he elec onic nose as an e ec i e ool o moni o he ed palm wee il pes (Rhynchopho us e ugineus Oli ie ) (Rizzolo e al., 2015). Elec onic nose also enables he iden i ica ion o species and sex o s ink bugs (Lan e al., 2008). CONCLUSION This esea ch deal wi h he compa ison o he smells o mealwo m (Teneb io moli o ) and supe wo m (Zophobas mo io) la ae; using simple, cheap and mobile de ice based on he A duino Mega pla o m. Al hough he de ice is simple, i enables measu ing and de ec ion o di e en s ages o edible insec culina y p ocessing. Conside ing he ood sa e y, elec onic nose can be used o moni o he p ocessing o edible insec and o dis inguish each species o edible insec in ce ain phases o culina y p ocessing. Elec onic noses can be he sou ce o da a used as inpu o HACCP, applied om ag icul u al p ima y p oduc ion, h ough culina y p ocessing and selling o he inal consume (p o ec ion o he consume ’s heal h). REFERENCES Adámko á, A., Kouřimská, L., Bo ko co á, M., Kulma, M., Mlček, J. 2016. 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Senso s and Ac ua o s B: Chemical, ol. 160, no. 1, p. 15-21. h ps://doi.o g/10.1016/j.snb.2011.07.002 Acknowledgmen s: The a c icle was suppo ed by p ojec no. FEKT-S-17-3934 U iliza ion o no el indings in mic o and nano echnologies o complex elec onic ci cui s and senso applica ions. Con ac add ess: Ma in Adámek, B no Uni e si y o Technology, Facul y o Elec ical Enginee ing and Communica ion, Depa men o Mic oelec onics, Technická 3058/10, 616 00 B no, Czech Republic, E-mail: adamek@ eec. u b .cz Anna Adámko á, Czech Uni e si y o Li e Sciences P ague, Facul y o Ag obiology, Food and Na u al Resou ces, Depa men o Quali y o Ag icul u al P oduc s, Kamýcká 129, 165 21 P ague 6 – Suchdol, Czech Republic, E-mail: [email p o ec ed]u.cz Ma ie Bo ko co á, Mendel Uni e si y in B no, Facul y o Ag onomy, Depa men o Zoology, Fishe ies, Hyd obiology and Ag icul u e, Zemědělská 1, 613 00 B no, Czech Republic, E-mail: ma ie.bo ko co [email protected] Jiří Mlček, Tomas Ba a Uni e si y in Zlin, Facul y o Technology, Depa men o Food Analysis and Chemis y, Va ecko a 275, 760 01 Zlin, Czech Republic, E-mail: [email p o ec ed] Ma ina Bednářo á, Mendel Uni e si y in B no, Depa men o In o ma ion Technology, Zemědělská 1, 613 00 B no, Czech Republic, E-mail: [email p o ec ed] Lenka Kouřimská, Czech Uni e si y o Li e Sciences P ague, Facul y o Ag obiology, Food and Na u al Resou ces, Depa men o Quali y o Ag icul u al P oduc s, Depa men o Mic obiology, Nu i ion and Die e ics, Kamýcká 129, 165 21 P ague 6 – Suchdol, Czech Republic, E-mail: [email p o ec ed]u.cz Jose Skácel, B no Uni e si y o Technology, Facul y o Elec ical Enginee ing and Communica ion, Depa men o Mic oelec onics, Technická 3058/10, 616 00 B no, Czech Republic, E-mail: [email p o ec ed]. u b .cz Michal Řezníček, Facul y o Elec ical Enginee ing and Communica ion, Depa men o Mic oelec onics, Technická 3058/10, 616 00 B no, Czech Republic, E-mail: [email p o ec ed] .cz