Production of Yogurt with Improved Functional Properties (Turkish with English Abstract)

Öz

In this study, the effect of using different incubation temperatures (25 ºC and 42 ºC) and kefir adjunct culture on microbiological, physicochemical and sensory properties of yogurt was investigated. Inulin, a prebiotic, was used as a fat replacer in non-fat yogurt production. According to the microbiological results, Lactobacillus countswere significantly affected by using adjunct culture and different incubation temperatures. Yogurts made with the yogurt culture and inulin at 42°C had the best score for sensory characteristics. Also, yogurt produced with adjunct kefir culture and inulin incubated at 42ºC had the second highest scores. Yogurt made with kefir culture and incubated at 42ºC received the lowest scores for overall sensorial characteristics. Yogurts produced with adjunct kefir culture had medium-sized holes (around 0.5 cm diameter) due to CO2 formation as a result of alcoholic fermentation. Using kefir culture in yogurt samples significantly affected the taste scores according to results of sensory analysis.

Anahtar Kelimeler

• Yogurt, Kefir, Prebiotic, Inulin

Fonksiyonel Özellikleri Geliştirilmiş Yoğurt Üretimi

Öz

Bu çalışmada, farklı inkübasyon sıcaklık (25 ºC ve 42 ºC) ve kefir destek kültürü kullanımının, yoğurtların mikrobiyolojik, fizikokimyasal ve duyusal özellikleri üzerine etkisi araştırılmıştır. Tam yağlı yoğurt örneklerinin yanı sıra, yağ ikamesi ve prebiyotik özelliği olan inulin yağsız yoğurt üretiminde kullanılmıştır. Mikrobiyolojik değerlendirmeler sonucunda özellikle Lactobacillus içerikleri, farklı kültür ve inkübasyon sıcaklık kombinasyonlarından önemli derecede etkilenmiştir. Kefir destek kültürü kullanılan yoğurtlarda mayalar da gelişmiştir. Duyusal analiz değerlendirmeleri sonucunda ise, en fazla puan alan ürün inulin ilaveli yoğurt kültürü ile yapılan yağsız yoğurt olurken, ikinci sırayı yine inulin ilaveli, kefir ve yoğurt kültürünün birlikte kullanıldığı ve 420C'de inkübe edilen yağsız yoğurt örneği almıştır. En düşük genel skoru, sadece kefir kültürü kullanılıp 420C'de inkübe edilen örnek almıştır. Kefir destek kültürü ile üretilen örneklerde CO2 oluşumundan dolayı orta büyüklükte gözenekler (yaklaşık 0.5 cm çaplı) tespit edilmiştir. Duyusal analiz sonuçlarına göre ürünlerde kefir kültür kullanımı yabancı tat üzerine önemli düzeyde etkili olmuştur.

Anahtar Kelimeler

• Yoğurt, kefir, prebiyotik, inulin

Kaynakça

1. Anonim. 1983. Gıda Maddeleri Muayene ve Analiz Metodları. T. C. Tarım, Orman ve Köyiflleri Bakanlığı. Koruma ve Kontrol Genel Müdürlüğü. Ankara.
2. Anonim. 1993. Converting chicory––not just a cup of coffee. Dairy Foods, Applied Technology, 94 (11): 112.
3. Atamer M., Sezgin E. 1986. Yoğurtlarda kuru madde artırımının pıhtının fiziksel özellikleri üzerine etkisi. Gıda, 11 (6): 327-331.
4. Fleet G.H. 2007. Yeasts in foods and beverages: impact on product quality and safety. Current Opinion in Biotechnology, 18: 170–175.
5. Goncu A, Alpkent Z. 2005. Sensory and chemical properties of white pickled cheese produced using kefir, yoghurt or a commercial cheese culture as a starter. International Dairy Journal, 15: 771–776.
6. Güzel-Seydim ZB, Seydim AC, Grene AK. 2000. Organic acids and volatile flavor components evolved during refrigerated storage of kefir. J Dairy Sci, 83: 275-277.
7. Güzel-Seydim ZB., Seydim AC, Grene AK, Bodine AB. 2000. Determination of organic acids and volatile flavor substances in Kefir during fermentation. J. Food Comp. Anal., 13 (1): 35-43.
8. Güzel-Seydim ZB, Seydim AC, Grene AK. 2005. Turkish kefir and Kefir Grains: Microbial Enumeration and Electron Microscopic Observation. J Int Dairy Tech, 58 (1): 25-29.

9. Güzel-Seydim Z, Grene AK, Tas T. 2006. Determination of Antimutagenic Properties of Some Fermented Milks Including Changes in the Total Fatty Acid Profiles including CLA. Internatinal Journal of Dairy Technology, 59 (3): 209-215.
10. Irigoyen A, Arana I, Castiella M, Torre P, Ibáñez FC. 2005. Microbiological, physicochemical, and sensory characteristics of kefir during storage. Food Chemistry, 90: 613–620.
11. Kılıç S, Uysal H, Kavas G, Kesenkafl H. 1999. Chemical, microbiological and sensory changes in ripening kefirs. Produced from starters and grains, Ege Üniversitesi, Ziraat Fakültesi Dergisi, 36 (1-2-3): 111-118.
12. Kim M and Shin HK. 1998. The water-soluble extract of chicory influences serum and liver lipid concentrations, cecal short-chain fatty acid concentrations and fecal lipid excretion in rats. J. Nutr, 128:1731-36.
13. Lawless HT, Heymann H, 1999. Sensory Evaluation of Food: Principles and Practices.A Chapman and Hall Food Science Book. An Aspen Publication.
14. Mattila-Sandholm T, Myllarinen P, Crittenden R, Mogensen G, Fonden R, Saarela M. 2002. Technological challenges for future probiotic foods, International Dairy Journal, 12: 173-182.
15. McCue P, Shetty K. 2005. Phenolic antioxidant mobilization during yoghurt production from soymilk using Kefir cultures. Process Biochemistry, 40: 1791–1797.
16. Palframan RJ, Gibson GR, Rastall RA. 2002. Effect of pH and dose on the growth of gut bacteria on prebiotic carbohydrates in vitro. Anaerobe, 8 (5): 287–292.
17. Paraskevopoulou A, Athanasiadis I, Blekas G, Koutinas AA, Kanellaki M, Kiosseoglou V. 2003. Influence of polysaccharide addition on stability of a cheese whey kefir-milk mixture. Food Hydrocolloids, 17: 615–620.
18. Rao VA. 2001. The prebiotic properties of oligofructose at low intake levels. Nutr. Res. 21 (6): 843–848.
19. Reddy BS, Hamid R, Rao CV. 1997. Effect of dietary oligofructose and inulin on colonic preneoplastic aberrant crypt foci inhibition. Carcinogen, 18: 1371-1374.
20. Reddy BS. 1999. Possible mechanisms by which pro- and prebiotics influence colon carcinogenesis and tumor growth. J. Nutr, 129: 1478–1482.
21. Roberfroid MB, VanLoo JA, Gibson GR. 1998. Prebiotics and synbiotics: concepts and nutritional properties. Brth. J. Nutr, 128: 11–19.
22. Rodrigues KL, Caputo LRG, Carvalho JCT, Evangelista J, Schneedorf JM. 2005. Antimicrobial and healing activity of kefir and kefiran extract. International Journal of Antimicrobial Agents, 25: 404–408.
23. SAS®. 1999. User’s guide: Statistics, Version 8 Edition. Cary, NC: SAS Inst., Inc.
24. Schneeman B. 1999. Fiber, Inulin and Oligofructose: Smilarities and Differences. Journal of Nutrition, 129 (7):1424.
25. Witthuhn RC, Schoeman T, Britz TJ. 2005. Characterisation of the microbial population at different stages of Kefir production and Kefir grain mass cultivation. International Dairy Journal, 15: 383–389.
26. Zubillagan M, Weill R, Postaire E, Goldman C, Caro R, Boccio J. 2001. Effect of probiotics and functional foods and their use in different diseases. Nutrition Research, 21: 569–579.