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8/10/2019 Lucrare de Doctorat n Industria Alimentar

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UNIVERSITATEA DE MEDICINI FARMACIEIULIU HAIEGANU

CLUJ-NAPOCA

IMPORTANA EXAMENULUIMICROBIOLOGIC PENTRU SIGURANA

ALIMENTELOR

REZUMATUL TEZEI DE DOCTORAT

Conductor tiinific DoctorandProf. Univ. Dr. Lia Monica JUNIE Mihaela Laura VIC

-2010-


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Cuprins

INTRODUCERE

1. STADIUL ACTUAL AL CUNOATERII N DOMENIU1.1. Contaminarea microbiologic a alimentelor

1.1.1. Obiectivul examenului microbiologic al alimentelor1.1.2. Sursa microorganismelor care contamineaz alimentele1.1.3. Condiiile necesare dezvoltrii microorganismelor n alimente1.1.4. Factorii de risc pentru calitatea microbiologica alimentelor

1.2. Categorii de alimente si microorganismele care le contamineaz1.2.1. Lapte si produse lactate

1.2.1.1. Contaminarea laptelui cu microorganisme

1.2.1.2. Factorii care influeneazevoluia microorganismelor n lapte1.2.1.3. Grupe de microorganisme nepatogene

1.2.1.4. Microflora patogendin lapte1.2.2. Carne i preparate din carne

1.2.2.1. Surse de contaminare a crnii cu microorganisme1.2.2.2. Factorii care influeneaza nmulirea microorganismelor n

carne i preparate din carne1.2.2.3. Parametrii microbiologici utilizai pentru studiul ncrcturii Crnii i

preparatelor din carne

1.2.3. Alte produse de origine animalsau non-animal1.2.3.1. Ou1.2.3.2. Miere de albine

1.2.3.3. Conserve

1.2.3.4. Pete i produse din pete1.2.3.5. Molute, crustacee, fructe de mare, pulpe de broasc, melci

1.2.3.6. Preparate i semipreparate culinare1.2.3.7. Aditivi i condimente1.2.3.8. Legume i fructe1.2.3.9. Pine i produse de panificaie1.2.3.10. Produse de patiserie, cofetrie i produse zaharoase1.2.3.11. Buturi nealcoolice1.2.3.12. Buturi alcoolice

1.3. Semnificaia prezenei microorganismelorn produsele alimentare1.3.1. Modificri din punct de vedere microbiologic suferite de alimente1.3.2. Toxiinfeciile alimentare

2. CERCETRI PROPRII

2.1.Evaluarea calitii microbiologice a ngheatei produs ntr-o fabric dengheat i ariscurilor n procesul de producie a acesteia

2.1.1. Condiii de contaminare a ngheatei cu microorganisme2.1.2. Material i metodede analiz2.1.3. Rezultate i discuii2.1.4. Concluzii

2.2. Studii privind contaminarea microbiologic cu E. colin probe de carne tocat i carnepreparat i analiza serotipurilor izolate


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2.2.1. Aspecte privind contaminarea cu E. coli a alimentelor i serotipurile prezente nacestea

2.2.2. Material i metodede analiz2.2.3. Rezultate i discuii2.2.4. Concluzii

2.3. Studii privindncrctura microbiana mierii de albine i proprietile antibacteriene

ale acesteia2.3.1. Determinri din punct de vedere microbiologic ale unor probe de miere din zonaTransilvaniei i riscurile condiionrii acesteia

2.3.1.1. Microorganismele prezente n miere i proveniena acestora2.3.1.2. Material i metodede analiz2.3.1.3. Rezultate i discuii2.3.1.4. Concluzii

2.3.2. Studiul proprietilor antibacteriene ale unor tipuri de miere recoltate din zonaTransilvaniei

2.3.2.1. Caracterul antimicrobian al mierii de albine

2.3.2.2. Material i metodede analiz2.3.2.3. Rezultate i discuii2.3.2.4. Concluzii

CONCLUZII GENERALE

BIBLIOGRAFIE

ANEXE

Cuvinte cheie: contaminare microbiologic, ngheat, Escherichia coli, carne tocat, carnepeparat, miere de albine, proprieti antibacteriene

Introducere

Influena alimentelor asupra sntii omului este un aspect de actualitate. Deoarece stilulde via al timpurilor noastre este foarte diferit de cel din trecut, n ciuda existenei noilordescoperiri, poate aprea riscul contaminrii alimentelor prin contaminani naturali sau care suntintrodusi accidental sau prin tratarea inadecvat a alimentelor.

Datorit tendinei actuale de consum a unor alimente proaspete, cu proprieti nutriionalesi senzoriale constante, apropiate de acelea ale produselor naturale, exist o preocuparea la nivelindustrial de obinere a unor produse cu procesare minim, cu aplicarea unor tratamente termicereduse sau chiar eliminarea acestora. n schimb, aceste produse pot fi instabile din punct devedere microbiologic.

Studiile efectuate au ncercat s atrag atenia asupra calitii microbiologice a unorcategorii de alimente considerate reprezentative din punct de vedere al consumatorilor. Prinrezultatele obinute, s-a demostrat importana examenului microbiologic pentru asigurareaconsumului de ctre populaie a unor produse alimentare sigure i pentru evitarea riscurilorposibile.


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1. Stadiul actual al cunoaterii n domeniu

Partea generalcuprinde considerente teoretice referitoare la tema abordati urmretetrei direcii: contaminarea microbiologic a alimentelor(obiectivul examenului microbiological alimentelor, sursa microorganismelor care contamineaz alimentele, condiiile necesaredezvoltrii microorganismelor n alimente i factorii de risc pentru calitatea microbiologic a

alimentelor);o trecere n revista principalelor categorii de alimente(lapte i produse lactate,carne i preparate din carne, alte produse de origine animal i non-animal), cu privire lacontaminarea acestora cu microorganisme; aspecte privind semnificaia prezeneimicroorganismelor n produsele alimentare: modificri din punct de vedere microbiologicsuferite de alimente, riscul producerii toxiinfeciilor alimentare.

2. Cercetri proprii

Obiectiveleacestui studiu au fost:

Evaluarea calitii microbiologice a unor probe de ngheatprodus ntr-o fabric dengheat i a riscurilor de contaminare care pot s aparpe parcursul procesului de

producie a acesteia.Studiul ncrcturii microbiologice cu bacterii din specia E. coli n probe de carnetocat i carne preparat destinata fi consumatgtiti analiza serotipurilor izolatedin probele necorespunztoare.Determinarea contaminrii microbiologice a unor probe de miere recoltate din zonaTransilvaniei i a riscurilor care apar n timpul procesrii acesteia n centre decolectare-ambalare.

Testarea activitii antibacteriene a unor tipuri de miere recoltate din zonaTransilvaniei asupra unor tulpini de bacterii.

2.1. Evaluarea calitii microbiologice a ngheatei produs ntr-o fabric de

ngheat ia riscurilor n procesul de producie a acesteia n acest capitol sunt prezentate:2.1.1. Condiiile de contaminare a ngheatei cu microorganisme;2.1.2. Material i metode de analiz: 40 de probe de ngheat, probe din materiile prime

utilizate i teste de sanitaie de pe fluxul tehnologic; Metodele utilizate pentru determinareanumrului total de bacterii aerobe mezofile, bacterii coliforme, E. coli i stafilococ coagulazo-pozitiv; Metodele utilizate pentru determinarea bacteriilor din genul Salmonella spp. ideterminareaListeria monocytogenes;

2.1.3. Rezultatele obinute: Rezultatele obinute prin analiza probelor de ngheat i amateriilor prime; Rezultatele testelor de sanitaie; Compararea rezultatelor privind numrul totalde bacterii aerobe i bacterii coliforme; Discutarea rezultatelor obinute.

Toate probele de ngheatanalizate se ncadreazn limite acceptabile privind siguranaalimentar deoarece n nici o prob numrul total de bacterii aerobe mezofile nu depete100000 UFC/g. Numrul minim obinut este 1,5x102, n timp ce numrul maxim este 3,0x104.ase probe (15%) prezint o ncrcturbacteriande ordinul 102, adic sub 1000 UFC/g. Ceamai mare parte (52,5%), adic 21 de probe prezint un numr de bacterii de ordinul 103 (ntre1000 i 10000 UFC/g).13 probe, adic 32,5% prezint un numr de bacterii de ordinul 104(peste10000 uniti formatoare de colonii/g).


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0

5000

10000

15000

20000

25000

30000

35000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Nr. proba

Nr.

totalbact./g

Prezena bacteriilor aerobe mezofile n probele de ngheat

n ceea ce privete numrul de bacterii coliforme, doar 23 de probe (57,5%) prezint unnumr de


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Escherichia coli pozitiv la -glucuronidaz; Metoda utilizat pentru serotipizarea tulpinilorizolate.

2.2.3. Rezultate i discuii: Rezultatele privind raportul probe corespunztoare/ probenecorespunztoare; Rezultatele serologice obinute i ncadrarea tulpinilor n grupe, corelate cupatogenitatea.

32 probe (64%) au prezentat rezultate corespunztoare Regulamentului (CE) 1441/2007,iar 18 probe (36%) au fost necorespunz

toare. Exist

o diferen

n ceea ce prive

te procentul de

probe fr ncrctur detectabil de E. coli (


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2.3. Studii privind ncrctura microbian a mierii de albine i proprietileantibacteriene ale acesteia

2.3.1. Determinri din punct de vedere microbiologic ale unor probe de miere din zonaTransilvaniei i riscurile condiionrii acesteia

Acest subcapitol prezint:2.3.1.1. Microorganismele prezente n miere i proveniena acestora2.3.1.2.

Material i metode de analiz

: 10 probe de miere

nainte

i dup

procesare;

metodele utilizate pentru determinarea numrului total de bacterii aerobe mezofile, numrului dedrojdii i mucegaiuri i umiditii probelor de miere.

2.3.1.3. Rezultate i discuiin ceea ce privete ncrctura cu drojdii i mucegaiuri, prin cercetrile efectuate nu au

fost identificate probe contaminate cu drojdii iar numrul de mucegaiuri nu depete 40/g nnici o prob. Cel mai frecvent ntlnit este genul Penicillium (n 35 % din probe), apoiAspergillus (n 20 % dintre probe). n cte o prob s-au determinat fungi din genurile Absidia(Mycocladus), RhizpusiFusarium.S-a demonstrat cexisto contaminare ncruciatdatoratcondiiilor improprii de igiena utilajelor sau aerului din ncperile de lucru, fapt care conduceapoi la contaminarea produselor.

Rezultatele privind numrul total de bacterii: n toate probele analizate acesta este sub100 UFC/g , ceea ce reprezinto contaminare redus, dar este evident o cretere a numrului debacterii n probele prelucrate fa de cele neprelucrate.

0

0.5

1

1.5

2

2.5

Pr. 1-2 Pr. 3-4 Pr. 5-6 Pr. 7-8 Pr. 9-

10

Pr. 11-

12

Pr. 13-

14

Pr. 15-

16

Pr. 17-

18

Pr. 19-

20

Proba

Log

UFC/g

Neprelucrata

Prelucrata

Dezvoltarea bacterian n probele de miere

Valorile obinute privind numrul total de bacterii precum i diversele tipuri de fungintlnite n probele de miere analizate indico contaminare din punct de vedere microbiologic ntimpul manipulrii de ctre apicultori i a tratamentelor primare la care este supus mierea.Avnd n vedere rezultatele obinute privind coninutul de ap n probele de miere, s-a observatcexisto legturntre aceste valori i numarul total de bacterii n probele respective.

2.3.1.4. Concluzii

Studiul efectuat a permis o investigaie privind calitatea igienic a unor probe de miere :numrul total de bacterii aerobe mezofile, nu depete 100 UFC/g.

S-a demonstrat prezena mucegaiurilor din genurile Penicillium,Aspergillus,Absidia,

Rhizpus,Fusarium, care, n condiii favorabile de dezvoltare pot conduce la multiplicare igenerarea de micotoxine.S-a demonstrat contaminarea din surse secundare datorit condiiilor de igieninadecvate

n timpul recoltrii, manipulrii si depozitrii. Studiul justific importana procesriicorespunztoare a mierii de albinen cadrul centrelor de colectare-ambalare.

Corelarea rezultatelor fizico-chimice i microbiologice este necesar pentru verificareacalitii i salubritii mierii de albine.


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S-a demonstrat necesitatea implementrii unui sistem de management pentru siguranaalimentelor eficient care asigurcondiii optime de monitorizare i controln cadrul condiionriimierii de albine, prevenind n acelai timp pericolul contaminrii acesteia.

2.3.2. Studiul proprietilor antibacteriene ale unor tipuri de miere recoltate din zonaTransilvaniei

Acest subcapitol prezint:

2.3.2.1. Caracterul antimicrobian al mierii de albine

2.3.2.2. Material i metode de analiz: 10 probe miere de albine cu diferite origini, 9tulpini de bacterii (E.coli, Staphylococcus aureus, Staphylococcus epidermidis, Salmonella

enteritidis, Salmonella anatum, Salmonella choleraesuis, Bacillus cereus, Bacillus subtilis iListeria monocytogenes), metode pentru determinarea inhibiiei bacteriene i metode utilizatepentru determinarea unor parametri fizico-chimici ai mierii.

2.3.2.3. Rezultate i discuiiToate probele de miere prezintactivitate antibacteriancu excepia unei probe de miere

de salcm care nu prezintinhibiie asupra nici uneia dintre tulpinile luate n studiu.Tulpina deE. coliprezintrezistenfade trei probe de miere; celelalte probe prezinto

activitate antibacterianmpotriva tulpinii deE. coliaproximativ egal, dar destul de redus. Celedoutulpini de stafilococi prezinto sensibilitate mare la aciunea mierii de albine, cu un plus nceea ce privete tulpina de S. epidermidis. Sensibilitatea tulpinilor de Salmonellaspp. la aciuneamierii este mai mare dect a tulpinii de E. coli, dar mai mic dect n cazul tulpinilor destafilococi, Salmonella choleraesuisfiind cea mai sensibildintre ele. Tulpina deB. cereusesterezistent la 5 din cele 10 probe de miere, iar B. subtilis prezint o vulnerabilitate mare laactivitatea mierii, prezentnd rezisten doar fa de o prob. Listeria monocytogenes are osensibilitate destul de ridicati prezintrezistenfade douprobe.

Se poate spune c exist o corelaie ntre originea mierii i activitatea bactericid aacesteia: mierea de man i cea de floarea soarelui prezinto activitate ridicat, avnd aciunempotriva tuturor tulpinilor de bacterii, probele de miere poliflorprezintde asemenea activitateridicatiar mierea de tei i salcm prezinto activitate mult mai sczut, att n ceea ce privetetulpinile asupra crora acioneaz, ct i n ceea ce privete intensitatea reaciei, adicdiametrulzonei de inhibiie. Din ceea ce reiese din datele de mai sus se poate vorbi i despre o corelaientre activitatea antibacteriana mierii i culoarea acesteia.

n ceea ce privete rezultatele analizelor fizico-chimice, nu exist nici o legtur ntreactivitatea antibacteriana probelor de miere i umiditatea sau pH-ul acestora. Pe de altparte,existcorelaii semnificative ntre activitatea antibacteriani aciditatea probelor de miere.

2.3.2.4. Concluzii

Cu o singur excepie, toate probele de miere de albine prezint activitate antibacterianasupra a cel puin patru dintre tulpinileluate n studiu.

Dintre tulpinile bacteriene testate cele doutulpini de stafilococ i cea deB. subtilissuntcele mai sensibile la aciunea antibacterian a probelor de miere.

Tulpinile de B. cereus, E. coli, L. monocytogenes i Salmonella spp. prezint rezistenfade cteva dintre probele de miere.

Existcorelaii ntre activitatea antibacteriani originea mierii de albine.Existo corelaie ntre activitatea antibacteriani culoarea mierii de albine.Din rezultatele analizelor fizico-chimice s-a demonstrat cexisto legturdirect ntre

caracterul antibacterian al mierii i aciditatea acesteia.


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Bibliografie selectiv

Tofan C. Microbiologie alimentar. Bucureti: Ed. AGIR; 2004.Staskel DM, Briley ME, Field LH, Barth SS. Microbial evaluation of foodservicesurfaces in Texas child-care centers. J Am Diet Assoc. 2007; 107 (5): 854-9.

Sneed J, Strohnbehn C, Gilmore SA, Mendonca A. Microbiological evaluation of

foodservice contact surfaces in Iowa assisted-living facilities. J Am Diet Assoc. 2004;104 (11): 1722-4.Glevitzky M, Perju D, Dumitrel G, Popa M, Vic M.Water activity - indicator offood safety and the factors that influence the biochemical stability of soft drinks.

Studia Universitatis Babe-Bolyai. Chemia. 2009; 1: 181-8.Stenfors Arnesen LP, OSullivan K, Granum PE. Food poisoning potencial of Bacilluscereus strains from Norvegian dairies. Int J Food Microbiol. 2007; 116 (2): 292-6.

Sobel J, Griffin PM, Slutsker L, Tauxe RV. Investigation of multistate foodbornedisease outbresaks. Public Health Rep. 2002; 117 (1): 8-19.

United States Food & Drug Administration. Enteroinvasive Escherichia coli. Internetaddress:http://vm.cfsan.fda.gov/~mow/chap16.html

United States Food & Drug Administration. Enteropathogenic Escherichia coli.Internet address:http://vm.cfsan.fda.gov/~mow/chap14.html

United States Food & Drug Administration. EnterotoxigenicEscherichia coli. Internetaddress:http://vm.cfsan.fda.gov/~mow/chap13.html

Tajik H, Shokouhi F. In vitroevaluation of antimicrobial efficacy of natural honey incomparison with sulfonamide derivatives. Journal of Animal and Veterinary

Advances. 2009; 8(1): 23-5.

Tumin N, Arsyiah N, Halim A, Shahjahan M, Izani N, Sattar M, et al. Antibacterialactivity of local malaysian honey. Malaysian Journal of Pharmaceutical Sciences.2005; 3 ( 2): 1-10.
http://vm.cfsan.fda.gov/~mow/chap16.htmlhttp://vm.cfsan.fda.gov/~mow/chap14.htmlhttp://vm.cfsan.fda.gov/~mow/chap13.htmlhttp://vm.cfsan.fda.gov/~mow/chap13.htmlhttp://vm.cfsan.fda.gov/~mow/chap14.htmlhttp://vm.cfsan.fda.gov/~mow/chap16.html


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Curriculum Vitae

1. Nume: VIC2. Prenume :MIHAELA LAURA

3.

Data i locul naterii : 23.10.1974, Cluj-Napoca4. Cetenie:romn5. Adresa: SEBE, str. Dorin Pavel nr. 60, jud. Alba6. Telefon: 0743891879

7. E-mail:[email protected];

[email protected]

8. Educaie i formare:

Nr.

crt.

Perioada Instituia denvmnt

Domeniul Titlul acordat/

diploma

obinut1. 2006-prezent Universitatea de

Medicina si FarmacieIuliu Hatieganu, Cluj-Napoca

Medicin Doctorand frfrecven

2. 1997-1998 Universitatea Babe Bolyai Cluj-Napoca,Facultatea de Biologie

Biologie Celular siMolecular

Diplom destudii

aprofundate

3. 1993-1997 Universitatea Babe Bolyai Cluj-Napoca,Facultatea de Biologie

Biologie Diplom delicen

4. 1989-1993 Liceul Teoretic LucianBlaga Sebe

Matematic Fizic Diplom debacalaureat

9. Experien profesional:

Nr.

crt.

Perioada Numele i adresa angajatorului Funcia/postul ocupat

1. aug. 2004-

prezent

Direcia Sanitar Veterinar ipentru Sigurana AlimentelorAlba, Alba Iulia str. Lalelor nr. 1A

Consilier / biolog - Serviciul

Sigurana Alimentelor,Profilul Microbiologie

Alimentar2. sept.1998-

aug. 2004

SC Bioef SRLFabrica de laptepraf Dotat, jud Alba

ef laborator / biologlaboratorul de microbiologie
mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]


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10.Activitate tiinific:

Lucrri tiinifice publicate in extenso n reviste indexate ISI Glevitzky M, Perju D, Dumitrel G, Popa M, Vic M.Water activity - indicator offood safety and the factors that influence the biochemical stability of soft drinks.

Studia Universitatis Babe-Bolyai. Chemia. 2009; 1: 181-8, ISSN: 1224-7154Popa M, Vic M, Axinte R, Glevitzky M, Varvara S. Correlations on themicrobiological and physical-chemical characteristics of different types of honey.

Journal of Environmental Protection and Ecology. 2009; 10(4): 1113-21, ISSN 1311-5065

Lucrri tiinifice publicate in extenso n reviste indexate CNCSIS, categoria B+ Popa M, Glevitzky M, Vic M, Varvara S. Study regarding the quality aromatizedwaters. Annales Universitatis Apulensis Series Oeconomica. 2008; 10(2): 849-53,ISSN 1454-9409

Vic M,Glevitzky M, Dumitrel G, Popa M, Varvara S. Microbiological role in hazard

analysis of natural honey processing. Journal of Agroalimentary Processes andTechnologies. 2009; 15(3): 353-60, ISSN 1453-1399

Popa M, Bosta R, Varvara S, VicM,Glevitzky M, Tomescu A. Study concerningmicrobiological and physicalchemical characteristics of Transilvania honey. AnaleleUniversitii din Oradea. 2009; 18(4): 814-8, ISSN 1582-5450Popa M, Vic M, Axinte R, Glevitzky M, Varvara S. Study concerning the honeyqualities in Transilvania region. Annales Universitatis Apulensis Series Oeconomica.

2009; 11(2): 1034-40, ISSN 1454-9409

Vic M,Glevitzky M, Dumitrel GA, Popa M, Todoran A. Microbiological quality ofice-cream produced in Alba County, Romania. Journal of Agroalimentary Processes

and Technologies. 2010; 16(1): 19-23, ISSN 1453-1399

Todoran A, Glevitzky M, Vic M.Studies regarding the quality of water and food forutilitarian dogs from Alba County, Romania. Journal of Agroalimentary Processes


Vic M, Glevitzky M, Dumitrel GA, Popa M. Study regarding Escherichia coliserotypes isolated in meat products from Alba County, Romania. Journal of

Agroalimentary Processes and Technologies. 2010; 16(3): 361-6, ISSN 1453-1399

Todoran A, Vic M, Glevitzky M, Dumitrel GA, Popa M. Water environmentalsituation of wells in Galda de Jos village, Romania: microbiological control. Chem.

Bull. Politehnica Univ. Timisoara. 2010; acceptat spre publicare, ISSN 0034-7752

Lucrri susinute la conferine / simpozioane tiinifice:

International Scientific Conference Challenges of Contemporary Knowledge BasedEconomy. Second Edition. Universitatea 1 Decembrie 1918, Alba Iulia, November28-29, 2008. Popa M, Glevitzky M, Vic M, Varvara S. Study regarding the qualityaromatized waters.

Timioaras Academic Days. XIth edition. Chemistry Symposium. Timioara, 28-29May 2009. Vic M,Glevitzky M, Dumitrel G, Popa M, Varvara S. Microbiologicalrole in hazard analysis of natural honey processing.

The 1th

International Conference on Food Chemistry, Engineering & Technology. TheXVI

th Edition of the SYMPOSIUM: Food Science, Processes and Technologies:


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New trends in food safety and processing. Faculty of Food Processing Technology.Timioara, 3-4 June 2010. Vic M, Glevitzky M, Dumitrel GA, Popa M. Studyregarding Escherichia coli serotypes isolated in meat products from Alba County,Romania.

11.Aptitudini i competene personale:

Limbi strinecunoscute: englez, francezCunotinte PC de baz: Microsoft Office, Outlook, InternetPermis de conducere: categoria B.


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IULIU HAIEGANUUNIVERSITY OF MEDICINE AND PHARMACY

CLUJ-NAPOCA

THE IMPORTANCE OF

MICROBIOLOGICAL EXAMINATION

TO FOOD SAFETY

PhD THESIS ABSTRACT

Scientific Supervisor PhD Student

Prof. Univ. Dr. Lia Monica JUNIE Mihaela Laura VIC

- 2010 -


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Contents

INTRODUCTION

1. THE PRESENT DEGREE OF KNOWLEDGE IN THE DOMAIN

1.1. Microbiological contamination of food

1.1.1. The objective of food microbiological examination1.1.2. The source of micro-organisms that contaminate food

1.1.3. Necessary conditions for micro-organisms development in food1.1.4. Risk factors in microbiological quality of food

1.2. Food categories and their contaminating micro-organisms1.2.1. Milk and dairy

1.2.1.1. Milk contamination with micro-organisms

1.2.1.2. The factors that influence micro-organisms evolution in milk1.2.1.3. Groups of non-pathogenetic micro-organisms

1.2.1.4. Pathogenetic flora in milk

1.2.2. Meat and meat products

1.2.2.1. Sources of meat contamination with micro-organisms1.2.2.2. Factors that influence micro-organisms spreading in meat and meat

products

1.2.2.3. Microbiological parameters used to study the charge of meat and meatproducts

1.2.3. Other products of animal or non-animal origin

1.2.3.1. Eggs

1.2.3.2. Honey1.2.3.3. Canned-food

1.2.3.4. Fish and fish products

1.2.3.5. Jellyfish, shell-fish, sea food, frog legs, snails

1.2.3.6. Coulinary products ans frozen food1.2.3.7. Additives and spices

1.2.3.8. Fruit and vegetables1.2.3.9. Bread and bakery

1.2.3.10. Pastry, cakes and sweet products

1.2.3.11. Non-alcoholic beverages

1.2.3.12. Alcoholic drinks

1.3. Significance of the preence of micro-organisms in food1.3.1. Micro-biological changes in food

1.3.2. Foodborne toxinfections

2. PERSONAL RESEARCH

2.1.Evaluation of micro-biological quality of ice-cream produces in an ice-cream factoryand the risks in the production process

2.1.1. Conditions of contamination of ice-cream with micro-organisms2.1.2. Material and analysis methods

2.1.3. Results and discussions

2.1.4. Conclusions

2.2. Studies regarding micro-biological contamination with E. coli in samples of minced

meat and prepared raw meat and the analysis of isolated sero-types


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2.2.1. Aspects regarding contamination withE. coliof food and the sero-types present in

it

2.2.2. Material and analysis methods2.2.3. Results and discussions

2.2.4. Conclusions

2.3. Studies regarding the microbian charge of honey ans its anti-bacterial properties2.3.1. Microbiological determinations for samples of honey from Transilvania and its riks

of contamination

2.3.1.1. Micro-organisms present in honey and their origin2.3.1.2. Material and analysis methods

2.3.1.3. Results and discussions

2.3.1.4. Conclusions

2.3.2. Study of anti-bacterial properties of some types of honey sampeled in Transilvania2.3.2.1. The anti-microbian character of honey

2.3.2.2. Material and analysis methods

2.3.2.3. Results and discussions

2.3.2.4. Conclusions

GENERAL CONCLUSIONS

BIBLIOGRAPHY

ANNEXES

Key words: microbiological contamination, ice-cream, Escherichia coli, minced meat,prepared raw meat, honey, anti-bacterial properties

Introduction

The influence of food in human health is a present interest issue. Because of the lifestyle

of our timesis so much different from the past, inspite all the new discoveries, the risk of foodcontamination through natural contaminants, or accidentally intruduced, or inadequate processing

of food, may occur.

Due to the present trend of fresh food consumption, with nutritional and sensory constant

properties, close to the natural products, there is a strong preoccupationat, industrial level,towards obtaining food with minimum processing, by applying reduced thermical treatments, or

even their elimination. Instead, these products may be instable from microbiological point of

view.

The studies performed have tried to point out the microbiological quality of some food

categories considered representative to the consumer. Through the results, the importance ofmicrobiological exam has been proven, for the safety of human consumption of safe food, in

order to avoid any possible hazard.


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1. The present degree of knowledge in the domain

The general section comprises theoretical considerents regarding the aproach to thetheme, and follows three directions: microbiological contamination of food (the objective of

microbiological exam, the source of food contaminating micro-organisms, the necessaryconditions of development of micro-organisms in food, and the risk factors to microbiologicalquality of food); a review of the main categorief of food (milk and dairy, meat and meat

products, other animal and non-animal origin foods), regarding their contamination with micro-

organisms; aspects regarding the significance of micro-organisms presence in food:microbiological changes that occur in food, the risk of foodborne toxinfections.

2. Personal research

The objectives of this study have been:

The evaluation of microbiological quality of ice-cream samples produced in an ice-

cream factory, and the contamination hazards along the process of production.The study of microbiological charge with E. colibacteria in minced meat samples,and in prepared raw meat meant to be cooked, as well as the analysis of the isolated

sero-types from unsatisfactory samples.

The determination of microbiological contamination for samples of honey harvestedfrom Transilvania, and the contamination hazard during its processing in gathering-packing centers.

Testing the anti-bacterial activity of some honey types harvested in Transilvania, uponsome bacteria.

2.1. Evaluation of micro-biological quality of ice-cream produces in an ice-cream factory

and the risks in the production processThis chapter presents:2.1.1. The conditions of contamination of ice-cream with micro-organisms;

2.1.2. Material and methods of analysis: 40 samples of ice-cream, samples from the raw

material used and sanitation tests on the technological flow; The metods used to detrminate the

total number of aerobic mesophile bacteria, E. coli and positive coagulant Staphylococcus;Methods used to determine Salmonella spp. bacteria and determination of Listeria

monocytogenes;

2.1.3. The results: The results from ice-cream and raw material analysis; Results of

sanitation tests; Comparison between the total number of aerobic and coliform bacteria;Discussion over the results.

All the ice-cream analysed samples range within the acceptable limits regarding the foodsafety, because in neither of them the number of aerobic mesophile bacteria does not excees100000 UFC/g. The minimum number is 1,5x10

2, while the maximum is 3,0x10

4. Six samples

(15%) present a bacterial charge of 102, under 1000 UFC/g. Most of them (52,5%), meaning 21

samples, have a number of bacteria of 103 (between 1000 and 10000 UFC/g). 13 samples ,

meaning 32,5% have a number of bacteria of 104(over 10000 units that form colonies/g).


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0

5000

10000

15000

20000

25000

30000

35000

1 2 3 4 5 6 7 8 9 1 0 1 1 12 13 14 15 16 17 18 19 20 2 1 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Sample number

Totalnr.ofbact./g

The presence of total aerob mesophile bacteria in ice cream samples

Regarding the number of coliform bacteria, just 23 samples (57,5%) have a number of


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2.2.2. Material and analysis methods: 50 samples of minced and prepared raw meat meant

to be consumed cooked; The method used to determine the microbian charge of Escherichia coli

positive to -glucuronidase; Method used to sero-type the isolated cultures.2.2.3. Results and discussions: The results regarding the ratio of adequate/inadequate

samples; Serologic results obtained and framing the cultures into groups, corelated with

pathogenity.32 samples (64%) gave results according to (CE) Regulation 1441/2007, and 18 samples

(36%) have been inadequate. There is a difference between the ratio of samples without

detectable charging of E. coli(


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2.3. Studies regarding the microbian charge of honey and its anti-bacterial

properties

2.3.1. Microbiological determinations for honey from Transilvania and the risks of itsconditioning

This subchapter presents:

2.3.1.1. Micro-oganisms present in honey and their origin2.3.1.2. Material and analysis methods: 10 samples of honey before and after processing;

methods used to determine the total number of mezophile aerobe bacteria, the number of yeasts

and moulds, and moisture content.2.3.1.3. Results and discussions

Regarding the charge of yeasts and moulds, the present research identified samples

contaminated with yeasts, and the number of moulds does not overcome 40/g in either of the

samples. The most frequent is thePenicilliumtype (in 35 % of the samples), thenAspergillus(in20 % of the samples). Fungus from Absidia (Mycocladus), Rhizpus and Fusarium types have

been found in one sample. There has been proven the existance of cross contamination due to

inadequate hygiene conditions or the air in the work spaces, fact that leads to products

contamination.The results regarding the total number of bacteria: all the analysed samples had less than

100 UFC/g, which means a low contamination, but there is an obvious increase in the number of

bacteria in processed samples compared to unprocessed ones.

0

0.5

1

1.5

2

2.5

Pr. 1-

2

Pr. 3-

4

Pr. 5-

6

Pr. 7-

8

Pr. 9-

10

Pr.

11-12

Pr.

13-14

Pr.

15-16

Pr.

17-18

Pr.

19-20

sample

Log

UFC/g

Unprocessed

Processed

Bacterial growth in honey samples

The values regarding the total number of bacteria, as well as various types of fungae in

the analysed honey samples indicate a microbiological contamination during manipulationprocess and primary treatments to wich the honey is submitted. Considering the results regarding

the moisture content in honey samples, there has been noticed that there is a conection between

these values and the total number of bacteria in the samples.

2.3.1.4. ConclusionsThe study allowed an investigation regarding the hygienic quality of honey samples: the

total number of aerob mesophile bacteria does not excede 100 UFC/g.

There has been proven the presence of moulds from types Penicillium,Aspergillus,Absidia, Rhizpus,Fusarium, which, in favourable conditions of development, may lead to

multiplication and toxines appearance.

Contamination from secondary sources has been proven, due to inadequate hygieneconditions during harvesting, manipulation and storage. The study justifies the importance of

adequate manipulation of honey in the colecting-packing centers.

The corelation of physico-chemical and microbiological results is necessary in order to

check the quality and salubrity of honey.


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There has been proven that there is necessary to implement an efficient food safety

quality management system to provide optimum monitoring and control conditions to honey

processing, thus preventing the risk of its contamination.

2.3.2. The study of anti-bacterial properties of some types of honey harvested in

TransilvaniaThis subchapter presents:

2.3.2.1. The anti-microbial character of honey

2.3.2.2. Material and analysis methods: 10 samples of honey with various origins, 9cultures of bacteria (E.coli, Staphylococcus aureus, Staphylococcus epidermidis, Salmonella

enteritidis, Salmonella anatum, Salmonella choleraesuis, Bacillus cereus, Bacillus subtilis iListeria monocytogenes), methods to determine the bacterial inhibition and methods to determine

some physico-chemical parameters of honey.2.3.2.3. Results and discussions

All the honey samples presented anti-bacterial activity, except for a sample of acacia

honey, wich does not present inhibition upon none of the cultures studied.

TheE. coliproves resistance to three honey samples: all the other honey samples manifestabout the same anti-bacterial activity against E. coli , relatively reduced, though. The two

Staphylococcus strains present a great sensitivity to the action of honey, with a plus regarding S.

epidermidis. The sensibility of Salmonellaspp. to the action of honey is higher than the E. colis,but smaller than in staphylococcus, Salmonella choleraesuisbeing the most sensitive of all. B.

cereusis resistant to 5 out of 10 honey samples, andB. subtilishas a high vulnerability to honey

activity, manifesting resistance just to a sample. Listeria monocytogenes has a rather highsensibility and manifests resistance just towards two samples.

We can assert that there is a correlation between the origin of honey and its bactericide

activity: sunflower and manna honey have a high activity, presenting influence against all

bacteria, the poli-flora honey samples also have high activity, and the linden and acacia honeypresent a much lower activity, regarding both the range of bacteria, and the intensity of reaction,

chiefly the area of inhibition. From the above data we can speak about a correlation between the

anti-bacterial activity of honey and its color.From the point of view of physico-chemical analysis, their results prove no conection

between the anti-bacterial activity and their moisture and pH. On the other hand, there are

significant correlations between the anti-bacterial activity and the acidity of the honey samples.

2.3.2.4. ConclusionsWith a single exception, all the honey samples present anti-bacterial activity against at

least four bacterial types submitted to the study.

From the bacteria types tested, the two Staphylococcusstrains andB. subtilisare the most

sensitive to the anti-bacterial action action of the honey samples.B. cereus, E. coli, L. monocytogenesi Salmonellaspp. manifest resistance agains some

of the honey samples.

There is a correlation between the origin and the anti-bacterial activity of honey.There is a correlation between the anti-bacterial activity and the color of honey.

From the results of physico-chemical analysis there has been proven a direct conection

between the anti-bacterial character of honey and its acidity.


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Selective bibliography

Tofan C. Food microbiology. Bucureti: Ed. AGIR; 2004.Staskel DM, Briley ME, Field LH, Barth SS. Microbial evaluation of foodservicesurfaces in Texas child-care centers. J Am Diet Assoc. 2007; 107 (5): 854-9.

Sneed J, Strohnbehn C, Gilmore SA, Mendonca A. Microbiological evaluation of

foodservice contact surfaces in Iowa assisted-living facilities. J Am Diet Assoc. 2004;104 (11): 1722-4.Glevitzky M, Perju D, Dumitrel G, Popa M, Vic M.Water activity - indicator offood safety and the factors that influence the biochemical stability of soft drinks.

Studia Universitatis Babe-Bolyai. Chemia. 2009; 1: 181-8.Stenfors Arnesen LP, OSullivan K, Granum PE. Food poisoning potencial of Bacilluscereus strains from Norvegian dairies. Int J Food Microbiol. 2007; 116 (2): 292-6.

Sobel J, Griffin PM, Slutsker L, Tauxe RV. Investigation of multistate foodbornedisease outbresaks. Public Health Rep. 2002; 117 (1): 8-19.

United States Food & Drug Administration. Enteroinvasive Escherichia coli. Internetaddress:http://vm.cfsan.fda.gov/~mow/chap16.html

United States Food & Drug Administration. Enteropathogenic Escherichia coli.Internet address:http://vm.cfsan.fda.gov/~mow/chap14.html

United States Food & Drug Administration. EnterotoxigenicEscherichia coli. Internetaddress:http://vm.cfsan.fda.gov/~mow/chap13.html

Tajik H, Shokouhi F. In vitroevaluation of antimicrobial efficacy of natural honey incomparison with sulfonamide derivatives. Journal of Animal and Veterinary

Advances. 2009; 8(1): 23-5.

Tumin N, Arsyiah N, Halim A, Shahjahan M, Izani N, Sattar M, et al. Antibacterialactivity of local malaysian honey. Malaysian Journal of Pharmaceutical Sciences.2005; 3 ( 2): 1-10.
http://vm.cfsan.fda.gov/~mow/chap16.htmlhttp://vm.cfsan.fda.gov/~mow/chap16.htmlhttp://vm.cfsan.fda.gov/~mow/chap16.htmlhttp://vm.cfsan.fda.gov/~mow/chap14.htmlhttp://vm.cfsan.fda.gov/~mow/chap13.htmlhttp://vm.cfsan.fda.gov/~mow/chap13.htmlhttp://vm.cfsan.fda.gov/~mow/chap14.htmlhttp://vm.cfsan.fda.gov/~mow/chap16.html


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Curriculum Vitae

1. Surname: VIC2. Name:MIHAELA LAURA

3. Date and place of birth: 23.10.1974, Cluj-Napoca

4. Citizenship:Romanian

5. Address: SEBE, str. Dorin Pavel nr. 60, jud. Alba6. Telephone: 0743891879

7. E-mail:[email protected];

[email protected]

8. Education and formation:

Nr.

crt.

Period Institution Domain Title received/

degree

1. 2006-present Iuliu HatieganuUniversity of Medicine

and Pharmacy, Cluj-Napoca

Medicine PhD student

2. 1997-1998 University Babe Bolyai Cluj-Napoca,Faculty of Biology

Celular and

Molecular Biology

Master degree

3. 1993-1997 University Babe Bolyai Cluj-Napoca,Faculty of Biology

Biology University

degree

4. 1989-1993 Theoretical High-School

Lucian Blaga SebeMathematicsPhysics

Bachelorsdegree

9. Professional experience:

Nr.

crt.

Period Name and address of the

employer

Job/poition

1. Aug. 2004-

present

Sanitary Veterinary and Food

Safety Directorate of Alba County,

Alba Iulia, 7 A, Lalelelor Street

Counselor/ biologistServiceof Food Safety, Profile of

Food Microbiology

2. Sept.1998-

Aug. 2004

SC Bioef SRLPowder MilkFactory, Dotat, AlbaCounty

Laboratory chief/ biologist Microbiology laboratory
mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]


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10. Scientific activity:

Scientific papers published in ISI index revues:

Glevitzky M, Perju D, Dumitrel G, Popa M, Vic M.Water activity - indicator offood safety and the factors that influence the biochemical stability of soft drinks.Studia Universitatis Babe-Bolyai. Chemia. 2009; 1: 181-8, ISSN: 1224-7154Popa M, Vic M, Axinte R, Glevitzky M, Varvara S. Correlations on themicrobiological and physical-chemical characteristics of different types of honey.

Journal of Environmental Protection and Ecology. 2009; 10(4): 1113-21, ISSN 1311-

5065

Scientific papers published in extenso in CNCSIS index revues, category B+:

Popa M, Glevitzky M, Vic M, Varvara S. Study regarding the quality aromatizedwaters. Annales Universitatis Apulensis Series Oeconomica. 2008; 10(2): 849-53,

ISSN 1454-9409Vic M,Glevitzky M, Dumitrel G, Popa M, Varvara S. Microbiological role in hazardanalysis of natural honey processing. Journal of Agroalimentary Processes and

Technologies. 2009; 15(3): 353-60, ISSN 1453-1399

Popa M, Bosta R, Varvara S, VicM,Glevitzky M, Tomescu A. Study concerningmicrobiological and physicalchemical characteristics of Transilvania honey. AnaleleUniversitii din Oradea. 2009; 18(4): 814-8, ISSN 1582-5450Popa M, Vic M, Axinte R, Glevitzky M, Varvara S. Study concerning the honeyqualities in Transilvania region. Annales Universitatis Apulensis Series Oeconomica.

2009; 11(2): 1034-40, ISSN 1454-9409

Vic M,Glevitzky M, Dumitrel GA, Popa M, Todoran A. Microbiological quality of

ice-cream produced in Alba County, Romania. Journal of Agroalimentary Processesand Technologies. 2010; 16(1): 19-23, ISSN 1453-1399

Todoran A, Glevitzky M, Vic M.Studies regarding the quality of water and food forutilitarian dogs from Alba County, Romania. Journal of Agroalimentary Processes


Vic M, Glevitzky M, Dumitrel GA, Popa M. Study regarding Escherichia coliserotypes isolated in meat products from Alba County, Romania. Journal of

Agroalimentary Processes and Technologies. 2010; 16(3): 361-6, ISSN 1453-1399

Todoran A, Vic M, Glevitzky M, Dumitrel GA, Popa M. Water environmentalsituation of wells in Galda de Jos village, Romania: microbiological control. Chem.

Bull. Politehnica Univ. Timisoara. 2010; acceptat spre publicare, ISSN 0034-7752

Scientific papers discused in conferences/ scientific symposiums:

International Scientific Conference Challenges of Contemporary Knowledge BasedEconomy. Second Edition. Universitatea 1 Decembrie 1918, Alba Iulia, November28-29, 2008. Popa M, Glevitzky M, Vic M, Varvara S. Study regarding the qualityaromatized waters.


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Timioaras Academic Days. XIth edition. Chemistry Symposium. Timioara, 28-29May 2009. Vic M,Glevitzky M, Dumitrel G, Popa M, Varvara S. Microbiologicalrole in hazard analysis of natural honey processing.

The 1th

International Conference on Food Chemistry, Engineering & Technology. TheXVI

th Edition of the SYMPOSIUM: Food Science, Processes and Technologies:

New trends in food safety and processing. Faculty of Food Processing Technology.

Timioara, 3-4 June 2010. Vic M, Glevitzky M, Dumitrel GA, Popa M. Studyregarding Escherichia coli serotypes isolated in meat products from Alba County,Romania.

11. Personal skills and competences:

Foreign languages: English and French

Basic PC skills: Microsoft Office, Outlook, Internet

Drivers licence, category B.