Meyveli Yoğurtlarda Bazı Patojen Bakterilerin Gelişimlerinin İncelenmesi

Bu çalışma da çilekli, şeftalili, kayısılı, muzlu ve sade yoğurtlar hazırlanarak, beş grup oluşturulmuş ve her bir gruba starter kültür ilavesi aşamasında E.coli, S.aureus, B.cereus suşları inoküle edilerek, meyveli yoğurtların patojen bakteriler üzerindeki etkisi araştırılmıştır. Hazırlanan meyveli yoğurtlarda 30 günlük muhafaza süresinin sonunda; asitlik (LA) 0.79-1.49 arasında değişmiş en düşük başlangıç asitliği kaysılı yoğurt iken muhafaza sonunda 1.49 ile çilekli yoğurt olmuştur ve aralarındaki farklılık istatistiksel olarak anlamlı bulunmuştur (p<0.05). Yine pH değerleri de 3.80 ile 4.62 arasında değişmiş ve 4.16 ile en düşük başlangıç pH’sı şeftalili yoğurt iken depolama süresi sonunda en düşük 3.91 pH ile muzlu yoğurtta olmuş ve yoğurtlar arasında istatistiksel açıdan da fark oluştuğu tespit edilmiştir (p<0.05). Yoğurtlardaki meyve çeşitlerinin patojenlerin gelişimi üzerinde etkili olduğu, S.aureus üzerine % 57.2-67.8 arasında, B.cereus üzerine % 6.6-45.9 arasında ve E.coli üzerine % 12.8-26.4 arasında inhibitör etkilerinin olduğu görülmüştür. Çilekli yoğurta tüm pataojenler % 17.9-67.8 arasında yıkımlanırken, şeftalili yoğurtta E.coli gelişimi olumsuz etkilenmemiş, B.cereus % 23.5 ve S.aureus % 58.9 oranında yıkımlanmıştır. Kaysılı yoğurtta yıkımlanma tüm patojenlerde % 12.8-64.1 arasında olmuştur. Muzlu yoğurtta da yine E.coli gelişimi olumsuz etkilenmezken B.cereus % 45.9 ve S.aureus % 63.8 oranında yıkımlandığı tespit edilmiştir. Meyveli yoğurtlarda meyvelerden kaynaklanan yüksek asitlik ve düşük pH değerleriyle yoğurtlar içerisindeki başta S.aureus olmak üzere B.cereus ve E.coli patojenleri üzerine inhibitör etkili oldukları tespit edilmiştir.

Anahtar Kelimeler:

Meyveli yoğurt, Patojen bakteri, Gelişim

Evaluation of the Growth of some Pathogen Bacteria in Fruit Yoghurts

In this study, five groups were established by preparing strawberry, peach, apricot, banana and plain yogurts and, by inoculating E. coli, S. aureus, and B. cereus strains during the starter culture addition phase of every group, the effects of pathogen bacteria on the fruit yogurts were investigated. At the end of 30 days of storage of prepared fruit yogurts, the acidity (LA) varied between 0.79 and 1.49; while the lowest initial acidity was found in apricot-added yogurt, the lowest acidity at the end of storage period was found in strawberry-added yogurt as 1.49 and the difference was found to be statistically significant (p<0.05). Again, the pH values varied between 3.80 and 4.62; the lowest initial pH was found in peach-added yogurt with 4.16 and the lowest pH at the end of storage period was found in banana-added yogurt with the value of 3.91, while the difference was statistically significant (p<0.05). It was observed that the fruit varieties in yogurts played role in growth of pathogens, and they had inhibitory effect on S. aureus between 57.2 and 67.8%, B. cereus between 16.6 and 45.9%, and E. coli between 12.8 and 26.4%. While all of the pathogens were degraded in strawberry-added yogurt by 17.9-67.8%, E. coli didn’t negatively affect the growth in peach-added yogurt and B. cereus was degraded by 23.5% and S. aureus by 58.9%. The degradation was 12.8-64.1% effective on all of the pathogens in apricot-added yogurts. In banana-added yogurt, while the E. coli growth was not affected negatively, it was determined that B. cereus was degraded by 45.9% and S. aureus by 63.8%. With high acidity and low pH levels caused due to of fruit in yoghurt, the fruit yogurts have found to have inhibitory effect on S. aureus and B. cereus and E. coli pathogens.

Keywords:

Pathogen Bacteria, Fruit Yoghurt, Growth,

PDF

___

Ahmed LI, Morgan SD, Hafez RS, Abdel-All AA (2014). Influence of yoghurt starter culture on viability of some pathogenic microorganisms in yoghurt. Int J Dairy Sci, 9(3),82–88. Akpınar A, Yerlikaya O, Kılıç S (2011). Antimicrobial activity and antibiotic resistance of Lactobacillus delbrueckii ssp. bulgaricus and S.thermophilus strains isolated from Turkish Homemade Yoghurts. Afr J Microbiol Res, 5 (6), 675–682. Aksu MY, Nas S (1996). Manufacturing techniques of concentrated mulberry juice and some of its physicochemical properties. Gıda, 21:83–88. Angelov M, Kostov G, Simova E, Beshkova D, Hristova PK (2009). Proto-cooperation factors in yogurt starter cultures. Rev Genie Indust, 3, 4–12. Anon (1983). Yogurt. Enumaration of Characteristic Microorganisims. IDF Standart E 117. Belgium Anon (1990). Official Methods of Analysis of the AOAC. 15 th ed. AOAC Inc., Arlington, USA. Ariaii P, Mahmoudi M, Amoli RI (2011). The Production of Fruity Yoghurt with Banana Flavor. Paper presented at the 2nd International Conference on Environmental Science and Technology. Aslım B, Beyatlı Y (1997). Köy ve kasaba yoğurtlarından izole edilen L. bulgaricus suşlarının metabolik ve antimikrobiyal aktiviteleri üzerine bir araştırma. Gıda, 22 (6), 441–447. Attaie R, Whalen PJ, Shahani KM, Amer MA (1987). Inhibition growth of S. aureus during production of acidophilus yoghurt. J Food Protec, 50 (3), 224–228. Belickova E, Tkacikova L, Naas HT et al. (2001). Staphylococci plate counts in foods of milk origin. Vet Med-Czeck, 46 (1), 24–27. Boycheva S, Dimitrov T, Naydenova N, Mihaylova G (2011). Quality characteristics of yogurt from goat’s milk, supplemented with fruit juice. Czech J Food Sci, 29 (1), 24–30. Canganella F, Ovidi M, Paganini S et al. (1998). Survival of undesirable microorganisms in fruit yoghurts during storage at different temperatures. Food Microbiol, 15:71–77. Çakmakçı S, Türkoğlu H, Çağlar A (1997). Meyve çeşidi ve muhafaza süresinin meyveli yoğurtların bazı kalite kriterleri üzerine etkisi. Atatürk Üniv Zir Faki Derg, 29 (3), 390–404 Dahiya RS, Speck ML (1968). Hydrogen peroxide formation by lactobacilli and its effect on Staphylococcus aureus. J Dairy Sci, 51 (10), 1568–1572. Dave RI, Shah NP (1996). Evaluation of media for selective enumeration of Streptococcus thermophilus, Lactobacillus delbrueckii spp. bulgaricus, Lactobacillus acidophilus, and bifidobacteria. J Dairy Sci, 79 (9), 1529–1536. Dogan M, Cankurt H, Toker ÖS, Yetim H, Sagdic O (2014). Effect of yoghurt or yoghurt serum on microbial quality of çig kofte. J Food Sci Technol, 51 (7), 1406–1410. Dong SK, Haeyoung N, Jeong HS, Yurina K, Sung KK, Changhoo C (2012). Antimicrobial activity of tinned strawberry fruits at different maturation stages. Kor J Hort Sci Technol, 30 (6), 769–775. Durak Y, Keleş F, Uysal A, Aladağ MO (2008). Konya yöresi taze ev yapımı yoğurtların mikrobiyolojik özelliklerinin araştırılması. Selçuk Üniv Zir Fak Derg, 22 (4), 113–117. Elmer M, James SL (2001). Applied Dairy Microbiology. Marcel Dekker: Technology and Industrial Arts. Gibbs PA (1987). Novel uses for lactic acid fermentation in food preservation. J Appl Bactl Symp, 63:51–58. Karagözlü C (1997). Meyveli Yoğurt Üretimi, Meyve Karışımı Hazırlanması, Yoğurtların Dayanma Süreleri ile Bazı Nitelikleri Üzerine Araştırmalar. Ege Üniversitesi, İzmir. Kılıç S (1990). Yoğurt kültürünü oluşturan L. bulgaricus ve S. thermophilus bakterilerinin antibakteriyel özellikleri üzerine bir araştırma. Gıda, 15 (6), 333–338. Meyer AL, Elmadfa I, Herbacek I, Micksche M (2007). Probiotic, as well as conventional yogurt, can enhance the stimulated production of proinflammatory cytokines. J Hum Nutr Diet, 20(6), 590–598. Michael M, Phebus RK, Schmidt KA (2010). Impact of a plant extract on the viability of Lactobacillus delbrueckii ssp. bulgaricus and S. thermophilus in nonfat yogurt. Int Dairy J, 20 (10), 665–672. Miller DM (2008). Development of Sequence of a Sequence-based Subtyping Method for Bacillus cereus Dairy Isolates Doctor of Philosophy, The Pennsyilvania State University, USA. Mohamed OM, Abdallai MO, Fawi NM, Ahmed SO, Mohamed EG, Ahmed GE (2015). Quality evaluation of stirred yoghurt flavoured with Guddaim (Grewia tenax) fruit. Asian J Agric Food Sci, 3 (1), 27–33. Nizamlıoğlu NM, Nas S (2004). Meyve ve sebzelerde bulunan fenolik bileşikler; yapıları ve önemleri. Gıda Teknol Elektronik Derg, 5 (1), 20–35. Nohynek LJ, Alakomi HL, Kähkönen MP et al. (2006). Berry Phenolics; antimicrobial properties and mechanisms of action against severe human pathogens. Nutr Cancer, 54 (1), 18–32. Okoye JI, Animalu IL (2009). Evaluation of physico-chemical and microbiological properties of stirred yoghurt stabilized with sweet potato (Ipomoea batatas) starch. Cont J Microbiol, 3, 27–30. Osaili TM, Taani M, Al-Nabulsi AA, Attlee A, Odeh RA, Holley RA, Obaid RS (2013). Survival of Escherichia coli O157:H7 during the manufacture and storage of fruit yogurt. J Food Safety, 33 (3), 282–290. Osborne RJ, Pritchard EW (1974). Preservation of Fruit Yoghurt by Preservatives and by Storage at Low Temperatures. XIX. International Dairy Congress, IE p 809-810. Özden A (2009). İnsan Beslenmesinde Yoğurdun Yararlı Etkileri. Güncel Gastroentoloji, 13 (4), 227–231. Şahan N, Akın S, Konar A (1999). Adana’da satılan meyveli yoğurtların fizikokimyasal, mikrobiyolojik ve duyusal özelliklerine depolama süresinin etkisi. Tr J of Agric Forestry, 23 (1), 73–80. Tamine AY, Robinson RK (2007). Yoghurt: Science and Technology. 3rd ed. Woodhead Publishing Limited, Cambridge, UK. Tarakçı A, Küçüköner E (2003). Physical, chemical, microbiological and sensory characteristics of some fruit-flavored yoghurt. YYÜ Vet Fak Derg, 14 (2), 10–14 Tirloni E, Bernardi C, Colombo F, Stella S (2015). Microbiological shelf life at different temperatures and fate of L.monocytogenes and E. coli inoculated in unflavored and strawberry yogurts. J Dairy Sci, 98 (7), 4318–4327. Tsiraki MI, Savvaidis IN (2016). The effects of citrus extract (Citrox©) on the naturally occurring microflora and inoculated pathogens, B.cereus and S. enterica, in a model food system and the traditional Greek yogurt-based salad Tzatziki. Food Microbiol, 53, 150–155. Uraltaş P, Nazlı B (1998). Piyasada satışa sunulan meyveli yoğurtların hijyenik kaliteleri üzerine araştırmalar. İstanbul Üniv Vet Fak Derg, 24 (2), 457–465.