VALORIZATION OF SMOKED TROUT SKINS AS A GELATIN SOURCE: ANALYSIS OF TECHNOLOGICAL AND STRUCTURAL PROPERTIES

Year 2025, Volume: 50 Issue: 5, 751 - 765, 15.10.2025

Şefik Tekle

https://doi.org/10.15237/gida.GD25079

Abstract

Fish processing by-products are increasingly used as alternative sources of functional biopolymers such as gelatin. This study aimed to evaluate the potential of smoked trout skins for gelatin production and to compare their properties with non-smoked trout gelatin. Gelatin was obtained by extraction from smoked trout skins. Technological and structural properties of smoked trout gelatin were analyzed and compared with non-smoked trout gelatin. Gelatin yield (9.89%) and gel strength (45 g) obtained from smoked skins were lower than those from non-smoked trout gelatin. Despite this, the emulsion activity index is higher compared to non-smoked trout gelatin, while the foam capacity and protein content remain at a similar level. The color difference obtained was quite significant, with a ΔE of 18.93 (very pronounced). Spectroscopic analysis confirmed that the functional groups were preserved. Smoked trout skin offers a good opportunity for food and other sectors as a sustainable and alternative gelatin source.

Keywords

Smoked trout skin , fish gelatin , functional properties , emulsifying activity , fish by-products

TÜTSÜLENMİŞ ALABALIK DERİLERİNİN JELATİN KAYNAĞI OLARAK DEĞERLENDİRİLMESİ: TEKNOLOJİK VE YAPISAL ÖZELLİKLERİN ANALİZİ

Abstract

Balık işleme yan ürünleri, jelatin gibi fonksiyonel biyopolimerlerin alternatif kaynağı olarak giderek daha fazla kullanılmaktadır. Bu çalışma, tütsülenmiş alabalık derilerinin jelatin üretimi için potansiyelini değerlendirmeyi ve özelliklerini tütsülenmemiş alabalık jelatini ile karşılaştırmayı amaçlamaktadır. Jelatin, tütsülenmiş alabalık derilerinden ekstraksiyon ile elde edilmiştir. Teknolojik ve yapısal özellikler analiz edilmiş ve tütsülenmemiş alabalık jelatini ile karşılaştırılmıştır. Tütsülenmiş derilerden elde edilen jelatin verimi (%9.89) ve jel kuvveti (45 g), gökkuşağı alabalığı jelatininden daha düşüktür. Buna rağmen, emülsiyon aktivite indeksi daha yüksek, köpük kapasitesi ve protein içeriği ise yakın bir seviyededir. Renk farklılığı ise oldukça belirgin (ΔE:18.93 - çok belirgin) olarak elde edilmiştir. Spektroskopik analizler, fonksiyonel grupların korunduğunu doğrulamıştır. Tütsülenmiş alabalık derisi, sürdürülebilir ve alternatif yeni bir jelatin kaynağı olarak gıda ve diğer sektörler için iyi bir fırsat sunmaktadır.

Keywords

Tütsülenmiş alabalık derisi , balık jelatini , fonksiyonel özellikler , emülsiyon aktivitesi , balık yan ürünleri

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