Yazar "Yuceer, Yonca Karagul" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • [ X ]
    Öğe
    Comparison of in vitro antioxidant activities of kefir, yogurt, and cheese produced from goat milk
    (Elsevier, 2026) Uzkuc, Hasan; Saritas, Sumeyye; Uzkuc, Nesrin Merve Celebi; Yuceer, Yonca Karagul; Esatbeyoglu, Tuba
    This study compared the physicochemical characteristics and in vitro antioxidant activities of kefir, yogurt, and cheese produced from the same batch of goat milk using specific starter cultures. The physicochemical properties of the samples, as well as the antioxidant capacity (CUPRAC and FRAP) of the in vitro digested samples were analyzed. Additionally, low molecular weight (<3 kDa) peptide fractions were isolated to evaluate their contribution to antioxidant capacity. The highest antioxidant activities (mM Trolox/g protein) based on the CUPRAC assay were observed in yogurt (123.30), followed by kefir (116.05) and cheese (89.35). In contrast, the highest FRAP values were in cheese (22.74), followed by kefir (14.22) and yogurt (14.12). Low molecular weight (<3 kDa) peptide fractions generally showed antioxidant activity similar to or higher than that of the corresponding complete digest samples. Findings highlight the antioxidant potential of fermented goat milk products, especially cheese and kefir, for functional dairy applications.
  • [ X ]
    Öğe
    Effects of heat treatment, starter culture, plant coagulant, and storage period on in vitro ACE inhibitory and antioxidant activity of goat cheese
    (Springer, 2025) Uzkuc, Hasan; Yuceer, Yonca Karagul
    The objective of this study was to determine the effects of heat treatment, starter culture addition, coagulant origin, and storage period on antioxidant and angiotensin-converting enzyme-inhibitory (ACE-I) activities of goat cheese. The bioactive potential of the cheeses was tested in the low molecular weight (< 3 kDa) fractions (LP) of in vitro digested samples containing bioactive peptides. The antioxidant activity of the cheeses was tested with ABTS [2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging and CUPRAC (Cupric ion reducing antioxidant capacity) assays. The interaction of heat treatment and starter culture addition affected the bioactive properties of the cheeses just as the storage process, while different coagulants had no effect. The highest ACE-I activities were 76.65-77.94% in heated and starter-added milk cheeses on the 1st day of storage. Starter-free raw milk cheeses had antioxidant activities ranging from 55.89 to 69.02 mM Trolox 100 mg(- 1) cheese in the ABTS assay on the 1st and 30th days, and from 13.06 to 17.52 mM Trolox g(- 1) cheese in the CUPRAC assay throughout the storage period. Results indicated that raw milk cheeses fermented by natural microbiota may exhibit an antihypertensive effect with over 50% ACE-I activity and reduce oxidative damage, demonstrating potential positive impacts on human health and suggesting their possible use in functional diets.
  • [ X ]
    Öğe
    Instrumental and Sensory Measurements of Ezine Cheese Texture
    (Sidas Medya A.Ş., 2010) Aday, Mehmet Seçkin; Caner, Cengiz; Yuceer, Yonca Karagul
    Instrumental and sensorial methods of texture profile analysis TPA were used to describe textural properties of Ezine cheese. Ezine cheeses produced by a local producer were stored in tin plate containers 2 kg each at 2-4°C for 12 months, and textural changes of cheese samples were determined during storage. Results of instrumental texture profile analysis showed that aging made cheese samples more adhesive and less cohesive. In sensory analysis, springiness and number of particles scores were lower at the end of the ripening than other days. Significant correlations were found between sensory attributes including rate of recovery and number of particles with instrumental springiness, instrumental gumminess, instrumental chewiness and instrumental resilience [TR] Bu çalışmada enstrümantal ve duyusal tekstür profil analizi TPA yöntemleri Ezine peynirinin tekstürel özelliklerini tanımlamak için kullanılmıştır. Lokal bir peynir üreticisi tarafından üretilen Ezine peynirleri teneke ambalajlarda 2 kg 2-4°C’de 12 ay boyunca depolanmış ve depolama süresince peynir örneklerinin tekstürel değişimleri belirlenmiştir. Enstrümantal tekstür profil analiz sonuçları peynirlerde olgunlaşma süresince iç yapışkanlığın arttığını ve dış yapışkanlığın ise azaldığını göstermiştir. Duyusal analizde depolama sonunda esneklik ve partikül sayısı değerlerinin azaldığı görülmüştür. Duyusal parametrelerden olan elastikiyet oranı ve partikül sayısı ile enstrümantal ölçümlerden olan esneklik, sakızımsılık, çiğnenebilirlik ve elastikiyet arasında yüksek korelasyon olduğu belirlenmiştir
  • [ X ]
    Öğe
    Valorization of Poppyseed Press Meal for Plant-Based Fermented Products: Impact of Starter Cultures and External Oleogel on Physicochemical and Sensory Properties
    (Springer, 2025) Yilmaz, Emin; Caliskan, Sule; Ok, Selcuk; Yuceer, Yonca Karagul
    This study aimed to evaluate the quality characteristics of plant-based fermented products (PBFP) prepared from poppyseed press meals. Two commercial lactic starter yogurt cultures, along with fresh dairy yogurt (Yo) used as culture, were tested and compared. In addition, the effect of external oleogel incorporation (-O) on product quality was examined. The proximate composition and basic physicochemical properties of the samples were analyzed. The products exhibited acceptable color characteristics, with a dominant light-brown hue. Samples fermented with lactic starter cultures reached pH values below 5.0, while those prepared with Yo and Yo-O cultures showed slightly higher pH values of 5.02 and 5.15, respectively. The water-holding capacity (WHC) exceeded 90% in all samples. Rheological analysis indicated gel formation, and stronger gels with higher storage modulus values were observed for samples with lower pH values, suggesting improved protein network formation through fermentation. Diverse volatile aromatics contents were developed for samples fermented with commercial lactic starter cultures. Sensory evaluations characterized the samples as sour, slippery, and mouth-covering protein gels. Overall, poppyseed press meal demonstrated strong potential as a base ingredient for commercial PBFP samples. Further research is recommended to improve the protein content of the final formulations.