Investigation of Consumer Reactions Towards Yoghurts Produced by Using Autochthonous Isolates

Yıl 2024, Cilt: 3 Sayı: 1, 59 - 67, 31.03.2024

Bülent Çetin , Haktan Aktaş

Öz

Microorganism diversity of yoghurt, an important fermented milk product, is decreasing, because only two strains are used in production and industrial yoghurts are used as starter cultures. In this study, a total of 114 traditional and exopolysaccharide (EPS)-yoghurt samples produced from cow milk using different combinations of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus were offered to consumers. Consumers were asked to evaluate some characteristics (general acceptability, packaging and labelling, flavor, texture, and odor) of yoghurt samples using a hedonic 5-point scale (1: dislike extremely; 2: dislike slightly; 3: neither like nor dislike; 4: like slightly; 5: like extremely). 60% of consumers scored general acceptability as "like extremely" for the samples. 13.30% of consumers preferred “neither like nor dislike” for packaging and labelling. In addition, consumers were asked to produce homemade yoghurt using these yoghurts and 73.30% of consumers liked flavor of the homemade yoghurt. Textural properties of homemade yoghurt with traditional and EPS-yoghurts were evaluated as "like extremely" by 66.70 and 73.30 % of consumers, respectively. Finally, odor properties of homemade yoghurt with traditional samples were liked by 73.30% of consumers. On the contrary, 46.70% of consumers liked odor of homemade yoghurt with EPS-yoghurt samples. Results showed that packaging and labelling of the yoghurt samples and odor characteristic of EPS-yoghurt need to be improved. It is thought that the yoghurt samples were generally liked by consumers and these products can be consumed as yoghurt or can be used as starter culture in homemade production. The products can be beneficial for national economy and preservation of diversity of yoghurt bacteria.

Anahtar Kelimeler

Yoghurt production, traditional yoghurt, EPS-yoghurt

Otokton İzolatlar Kullanılarak Üretilen Yoğurtlara Yönelik Tüketici Beğenisinin İncelenmesi

Öz

Üretiminde sadece iki bakterinin kullanılması ve endüstriyel yoğurtların starter kültür olarak kullanılması gibi nedenlerden dolayı önemli bir fermente süt ürünü olan yoğurdun mikroorganizma çeşitliliğinde azalmalar/kaybolmalar görülmektedir. Bu çalışmada, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus’un farklı kombinasyonları ile inek sütünden üretilmiş 114 geleneksel ve EPS-yoğurt örneği tüketici beğenisine sunulmuştur. Tüketicilerden söz konusu yoğurtların bazı özelliklerini (genel kabul edilebilirlik, ambalaj ve etiket, tat, tekstür ve koku) 5 noktalı hedonik skala (1: hiç beğenmedim; 2: beğenmedim; 3: kararsızım; 4: beğendim; 5: çok beğendim) yardımıyla değerlendirmeleri istenmiştir. Tüketicilerin % 60’ı her iki örneğin genel kabul edilebilirlik skorlarını “aşırı derecede beğendim” şeklinde değerlendirmişlerdir. Tüketicilerin % 13,30’u örneklerin ambalaj ve etiket özelliklerine “ne iyi ne de kötü” şeklinde puanlamışlardır. Ayrıca, tüketicilerden bu yoğurtları kullanarak ev yapımı yoğurt üretmeleri istenmiş ve tüketicilerin % 73,30’u bu ev yapımı yoğurtların tat özelliklerini beğenilmiştir. Geleneksel ve EPS-yoğurtlardan üretilen ev yapımı yoğurtların tekstürel özellikleri ise sırasıyla tüketicilerin % 66,70 ve 73,30’u tarafından “aşırı derecede beğendim” şeklinde değerlendirilmiştir. Son olarak, geleneksel örneklerden üretilen ev yapımı yoğurtların kokusu tüketicilerin % 73,30’u tarafından beğenilmiştir. Bunun aksine, EPS-yoğurttan üretilen ev yapımı yoğurtların kokusu tüketicilerin % 46,70’i tarafından beğenilmiştir. Bu sonuçlar, yoğurt örneklerinin ambalaj ve etiket özellikleri ile EPS-yoğurtların koku özelliklerinin iyileştirilmesi gerektiğini göstermiştir. Bunların dışında, yoğurt örneklerinin genel olarak tüketiciler tarafından beğenildiği ve bu ürünlerin yoğurt olarak tüketilebileceği veya ev yapımı üretimlerde starter kültür olarak kullanılabileceği düşünülmektedir. Bu ürünlerin ülke ekonomisine ve yoğurt bakterilerinin çeşitliliğinin korunmasına faydalı olacağı düşünülmektedir.

Anahtar Kelimeler

Yoğurt üretimi, geleneksel yoğurt, EPS-yoğurt, tüketici tepkisi

Kaynakça

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