YOĞURT FERMANTASYONU SIRASINDA SALMONELLA ENTERİTİDİS’İN FARKLI İNOKÜLASYON KOŞULLARINDA CANLI KALMA DURUMUNUN ARAŞTIRILMASI

Abstract

Yoğurt düşük pH (pH 4.2-4.5) içeriği ile mikrobiyolojik açıdan genellikle güvenilir gıda olarak düşünülmektedir. Diğer taraftan Salmonella spp. süt ürünleri tüketimi ile ilişkili hastalıkların en sık nedeni olarak gösterilmektedir. Bu çalışmada geleneksel yoğurt kültürü kullanılarak yapılan yoğurtlarda, Salmonella Enteritidis’in süte fermantasyon öncesi farklı inokülasyon düzeylerinde bulaştırılması durumunda fermantasyon süresince canlı kalma durumu araştırılmıştır. Sayım yapılan her aşamada pH ölçümü yapılmıştır. Fermantasyon sonunda S. Enteritidis sayısı yaklaşık 3; 5 ve 7 log KOB/mL düzeylerinde bulaşma durumları için sırasıyla 2.95; 4.93, 7.05 log KOB/g’dan 3.26; 5.55; 6.98 log KOB/g’a ulaşmıştır. Farklı inokülasyon koşullarında örneklerin pH değerleri arasında fark görülmemiş (P>0.05), fermantasyon süresince pH değeri 6.3’ten 4.5’e düşmüştür. Çalışma düşünülenin aksine, Salmonella’nın yoğurt fermantasyonu süresince düşük inokülasyon düzeyinde dahi canlılığını sürdürebilmesi bakımından önem taşımaktadır. 

Keywords

• Yoğurt,Salmonella,fermantasyon,canlı kalma

INVESTIGATION of SURVIVAL of SALMONELLA ENTERITIDIS DURING YOGHURT FERMENTATION at DIFFERENT INOCULATION LEVELS

Abstract

Yoghurt has generally been considered microbiologically safe as a consequence of low pH (pH 4.2-4.5). On the other hand, Salmonella spp. is reported the most common cause of diseases associated with consumption of dairy products. In this study, survival of Salmonella Enteritidis at different inoculation levels during fermentation of yoghurt prepared using traditional yoghurt cultures was investigated. The pH of the samples was monitored when the enumeration procedures were carried out. At the end of the fermentation process, the counts of S. Enteritidis reached from 2.95; 4.93; 7.05 to 3.26; 5.55; 6.98 log CFU/g for the three initial inoculum levels (3; 5 and 7 log CFU/mL), respectively. The changes of pH values were similar for all experiments (P>0.05), and the pH dropped from 6.3 to 4.5 during the fermentation period. In contrast to common belief, the study showed that this pathogen can survive in milk fermentation process even at low contamination level.

Keywords

• Yoghurt,Salmonella,fermentation,survival

References

1. Kalui CM, Mathara JM, Kutima PM. 2010. Probiotic potential of spontaneously fermented cereal based foods - a review. Afr J Biotechnol, 9 (17): 2490-2498.
2. Madhu, Shiva Prakash, M, Neetu. 2013. Yoghurt is excellent vehicle for traveling probiotics to public health. Int J Food Nutr Sci, 2 (1): 126-137.
3. Hrnjez D, Vaštag Ž, Milanovic S, Vukic V, Ilicic M, Popovic Lj, Kanuric K. 2014. The biological activity of fermented dairy products obtained by kombucha and conventional starter cultures during storage. J Funct Foods, 10:336-345.
4. Sfakianakis P, Tzia C. 2014. Conventional and innovative processing of milk for yogurt manufacture; development of texture and flavor: A review. Foods, 3: 176-193.
5. Bachrouri M, Quinto EJ, Mora MT. 2006. Kinetic parameters of Escherichia coli O157:H7 survival during fermentation of milk and refrigeration of home-made yoghurt. Int Dairy J, 16 (5): 474-481.
6. Canganella F, Nespica ML, Giontella D, Trovatelli LD. 1999. Survival of Enterobacter cloacae and Pseudomonas paucimobilis in yoghurts manufactured from cow's milk and soy milk during storage at different temperatures. J Microbiol Res, 154: 15-21.
7. Massa S, Altieri C, Quranta V, De Pace R. 1997. Survival of Escherichia coli O157:H7 in yoghurt during preparation and storage at 4 oC. Lett Appl Microbiol, 24: 347-350.
8. Pazakova J, Turek P, Laciakova A. 1997. The survival of Staphylococcus aureus during the fermentation and storage of yoghurt. J Appl Microbiol, 82: 659-662.

9. Morgan D, Newman CP, Hutchinson DN, Walker AM, Rowe B, Majid F. 1993. Verotoxin producing Escherichia coli O157 infections associated with the consumption of yoghurt. Epidemiol Infect, 111: 181-187.
10. Centers for Disease Control and Prevention (CDC). 2011. Estimates of foodborne illness in the United States. http://www.cdc.gov/foodborneburden/PDFs/FACTSHEET_A_FINDINGS_updated4-13.pdf (Accessed 06 March 2016).
11. Scallan E, Hoekstra RM, Angulo FJ, Tauxe RV, Widdowson MA, Roy SL, Jones JL, Griffin PM. 2011. Foodborne illness acquired in the United States-major pathogens. Emerg Infect Dis, 17 (1): 7-15.
12. Crim SM, Iwamoto M, Huang, JY, Griffin PM, Gilliss D, Cronquist AB, Cartter M, Tobin-D’Angelo M, Blythe D, Smith K, Lathrop S, Zansky S, Cieslak PR, Dunn J, Holt KG, Lance S, Tauxe R, Henao OL. 2014. Incidence and trends of infection with pathogens transmitted commonly through food - foodborne diseases active surveillance network, 10 U.S. Sites, 2006–2013. Centers for disease control and prevention (CDC). Morb Mortal Wkly Rep, 63 (15): 328-332.
13. Szczawıńska ME, Szczawıński J. 2011. Effect of storage temperature on survival rate of Salmonella Enteritidis in yoghurt. Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru, 41: 243-246.
14. FDA. 2012. Interactive food defense workshop with government & industry representatives at the 2012 food safety summit. http://www.fda.gov/downloads/Food/FoodDefense/UCM303901.pdf (Accessed 06 March 2016).
15. Bachrouri M, Quinto EJ, Mora MT. 2002. Survival of Escherichia coli O157:H7 during storage of yogurt at different temperatures. J Food Sci, 67 (5): 1989-1903.
16. Ogwaro BA, Gibson H, Whitehead M, Hill DJ. 2002. Survival of Escherichia coli O157:H7 in traditional African yoghurt fermentation. Int J Food Microbiol, 79: 105-112.
17. Akkaya L, Telli R, Sağdıç O. 2009. Growth-death kinetics of Listeria monocytogenes in strained yogurt. Int J Food Prop, 12: 705-712.
18. Bednarko-Młynarczyk E, Szteyn J, Białobrzewski I, Wiszniewska-Łaszczych A, Liedtke K. 2015. Modeling the kinetics of survival of Staphylococcus aureus in regional yogurt from goat’s milk. Pol J Vet Sci, 18 (1): 39-45.
19. Al-Haddad KSH. 2003. Survival of Salmonellae in bioyoghurt. Int J Dairy Technol, 56: 199-202.
20. Alvarez-Ordonez A, Valdes L, Bernardo A, Prieto M, Lopez, M. 2013. Survival of acid adapted and non-acid adapted Salmonella Typhimurium in pasteurized orange juice and yogurt under different storage temperatures. Food Sci Technol Int, 19 (5): 407-414.
21. Anonim 2005. Merck Gıda Mikrobiyolojisi Uygulamaları. Ed: A. K. Halkman. Başak Matbaacılık Ltd. Şti., Ankara, 358 sayfa.
22. Kumbhar SB, Ghosh JS, Samudre SP. 2009. Microbiological analysis of pathogenic organisms in indigenous fermented milk products. Adv J Food Sci Technol, 1 (1): 35-38.
23. Cirone K, Huberman Y, Morsella C, Méndez L, Jorge M, Paolicchi F. 2013. Growth of Mycobacterium avium subsp. paratuberculosis, Escherichia coli, and Salmonella Enteritidis during Preparation and Storage of Yogurt. ISRN Microbiol, 1-7.
24. Suskovic J, Kos B, Beganovic J, Pavunc AL, Habjanic K, Matosic S. 2010. Antimicrobial activity - the most important property of probiotic and starter lactic acid bacteria. Food Technol Biotech, 48 (3): 296-307.
25. Shen HW, Yu RC, Chou CC. 2007. Acid adaptation affects the viability of Salmonella Typhimurium during the lactic fermentation of skim milk and product storage. Int J Food Microbiol, 114: 380-385.
26. Tan SM, Lee SM, Dykes GA. 2014. Buffering effect of chicken skin and meat protects Salmonella enterica strains against hydrochloric acid but not organic acid treatment. Food Control, 42: 329-334.
27. Oscar TP. 1998. Growth kinetics of Salmonella isolates in a laboratory medium as affected by isolate and holding temperature. J Food Protect, 61 (8): 964-968.