Naslov (srp)

Karakterizacija mikrobiote prirodno fermentisane pirotske "peglane" kobasice tokom zrenja i gotovog proizvoda : doktorska disertacija

Autor

Bogdanović, Svetlana, 1984-

Doprinosi

Stanković, Slaviša, 1965-
Vesković-Moračanin, Slavica, 1966-
Jelušić, Aleksandra, 1992-
Berić, Tanja, 1974-
Medić, Olja, 1991-
Dimkić, Ivica, 1983-

Opis (srp)

Pirotska „peglana“ kobasica je tradicionalna, fermentisana kobasica, koja se pravi od različitihvrsta mesa, soli i začina, a bez dodatka starter kultura. Testirani su uzorci kobasica šest proizvođačaod kojih su neki koristili standardnu a neki nestandardnu recepturu. Ukupni diverzitet bakterija jeispitivan u gotovom proizvodu i tokom zrenja u različitim vremenskim tačkama korišćenjemodgajivačkog i neodgajivačkog (sekvenciranje gena za 16S rRNK) pristupa. Genetički polimorfizampredstavnika različitih grupa bakterijskih izolata određivan je korišćenjem rep-PCR i RAPD-PCRtehnika sa specijalizovanim prajmerima. Rezultati identifikacije sekvenciranjem gena za 16S rRNKukazuju na prisustvo samo dve vrste bakterija mlečne kiseline, Lactobacillus sakei (76%) iLeuconostoc mesenteroides (24%). U poređenju sa drugim prajmerima, najveću diskriminatornu moćpokazao je prajmer GTG5, kod većine testiranih izolata. Sekvenciranjem naredne generacije utvrđenaje dominacija predstavnika iz razdela Proteobacteria i Firmicutes u svim proučavanim uzorcima.Tokom procesa zrenja uočen je trend povećanja zastupljenosti predstavnika Firmicutes (sa 33,5% na63,5%) i smanjenje udela Proteobacteria (sa 65,4% na 22,3%). Metabarkoding analiza je pokazalada su dominantni bakterijski rodovi tokom procesa zrenja kobasice bili: Lactobacillus,Photobacterium, Leuconostoc, Weissella i Lactococcus, dok su detektovani i Carnobacterium,Brochothrix i Acinetobacter. Odgajivačkim pristupom je utvrđeno prisustvo vrsta Lactobacillus sakeii Leuconostoc mesenteoides u svim fazama zrenja. Upoređen je sastav bakterijskih zajednica ugotovom proizvodu svakog testiranog proizvođača. U uzorcima PK1 i PK2 pokazano je najvećebogatstvo bakterijskih vrsta. Predstavnici razdela Firmicutes su bili dominantni u uzorcima PK3,PK4, PK5 i PK6, dok su predstavnici Proteobacteria bili najzastupljeniji u uzorcima PK1 i PK2. Uzavisnosti od uzorka, dominiraju vrste roda Lactobacillus, L. sakei i L. algidus, dok je rodLeuconostoc nađen u svim uzorcima. U gotovom proizvodu i tokom zrenja u različitim vremenskimtačkama određivane su i fizičko-hemijske osobine kobasice. Primećeno je smanjenje pH vrednosti,aktivnosti vode i sadržaja vlage, i povećanje sadržaja proteina i masti. Različite recepture i različitovreme zrenja pirotske “peglane” kobasice nisu imale značajan uticaj na profil masnih kiselina, ali suimale značajan efekat na instrumentalne parametre boje. Takođe, zabeležene su i statistički značajnerazlike ispitivanih parametara teksture između kobasica proizvedenih po različitim recepturama.Različiti udeli upotrebljenog mesa prouzrokovali su značajne razlike u pogledu senzornihkarakteristika.

Opis (srp)

Biologija - Mikrobiologija / Biology- Microbiology Datum odbrane: 01.07.2023.

Opis (eng)

Pirot "ironed" sausage is a traditional fermented sausage made from various meats, salt, andspices, without the addition of starter cultures. Sausage samples from six producers were studied,some of which used standard and some non-standard recipes. Total bacterial diversity was studied inthe finished product and during ripening at different time points using cultivating and non-cultivatingmethods. Genetic polymorphism of representatives of different groups of bacterial isolates wasdetermined using rep-PCR and RAPD-PCR techniques with specific primers. The results of 16SrRNA gene sequencing indicated the presence of only two species of lactic acid bacteria,Lactobacillus sakei (76%) and Leuconostoc mesenteroides (24%). Compared to other primers, theGTG5 primer showed the highest discriminatory power for most of the isolates tested. Next generationsequencing showed that representatives of Proteobacteria and Firmicutes dominated in all samplestested. During maturation, a trend of increasing the proportion of Firmicutes representatives (from33.5% to 63.5%) and decreasing the proportion of Proteobacteria (from 65.4% to 22.3%) wasobserved. Metabarcoding analysis showed that the dominant bacterial genera during the sausageripening process were the following: Lactobacillus, Photobacterium, Leuconostoc, Weissella andLactococcus, while Carnobacterium, Brochothrix and Acinetobacter were also detected. Thepresence of the species Lactobacillus sakei and Leuconostoc mesenteoides at all stages of maturationwas detected in the cultivation approach. The composition of bacterial communities in the finalproduct of each tested producer was compared. Samples PK1 and PK2 showed the highest abundanceof bacterial species. Representatives of the Firmicutes dominated in samples PK3, PK4, PK5 andPK6, while representatives of Proteobacteria were most abundant in samples PK1 and PK2.Depending on the sample, species of the genus Lactobacillus, L. sakei and L. algidus dominated,while the genus Leuconostoc was found in all samples. The physical and chemical properties of thesausage were also determined in the finished product and during ripening at different times. Decreasesin pH, water activity, and moisture content were found, as well as increases in protein and fat content.Different recipes and different ripening times of Pirot "ironed" sausage had no significant effect onthe fatty acid profile, but a significant effect on the instrumental color parameters. Statisticallysignificant differences were also found in the investigated texture parameters between sausagesproduced according to different recipes. Different proportions of meat used resulted in significantdifferences in sensory properties.

Jezik

srpski

Datum

2023

Licenca

Ovo delo je licencirano pod uslovima licence
Creative Commons CC BY-NC-ND 3.0 AT - Creative Commons Autorstvo - Nekomercijalno - Bez prerada 3.0 Austria License.

http://creativecommons.org/licenses/by-nc-nd/3.0/at/legalcode

Predmet

OSNO - Opšta sistematizacija naučnih oblasti, Mikrobiologija. Bakteriologija

OSNO - Opšta sistematizacija naučnih oblasti, Mikrobiologija. Bakteriologija

pirotska „peglana“ kobasica, metabarkoding, fizičko-hemijske analize, tehnološki parametri, Lactobacillus sakei, Leuconostoc mesenteoides

Pirot ‘ironed’ sausage, metabarcoding, physical and chemical analysis, technological parameters, Lactobacillus sakei, Leuconostoc mesenteoides

579.6:637.523(043.3)