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

Abstract

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.

Keywords

• Yogurt, Kefir, Prebiotic, Inulin

Fonksiyonel Özellikleri Geliştirilmiş Yoğurt Üretimi

Abstract

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.

Keywords

• Yoğurt, kefir, prebiyotik, inulin

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